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Arcade Collecting => Restorations & repair => Topic started by: vapuser on January 28, 2020, 07:10:06 am

Title: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 28, 2020, 07:10:06 am
Good morning, I own an Atari Centipede cocktail table game. The original problem was that the game would not power on anymore. So I took the power supply out of the unit and noticed that some of the voltages were a little off. I purchased and replaced the 27000 uf big blue capacitor and also the bridge rectifier circuit board. The voltages from that circuit now seems to be more in-line with the schematic. Since I took this power supply out of the unit over 5 years ago I can not remember where one of the plugs get plugged into. Specifically, it is a connector that comes off the bottom of the on/off switch. The on/off switch leads go into a wiring harness and this connector comes off that wiring harness just a few inches away. It's a six pin connector. There are two black wires, two white wires and a green wire in this connector. So it appears to be a power connector. As a matter of fact I used that connector to test for continuity of the on/off switch. I wanted to determine which position was "on" and which position was "off". I'm hoping someone can help me determine where this connector gets plugged into. I'm totally stumped.  I would love to see this game come back to life. Thanks in advance for your help.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 08:47:14 am
I have a centipede cocktail at home. I get off work between 2 and 4pm CST. I can take a look at mine then and help you out.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 28, 2020, 10:43:07 am
Thanks Mike. :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: pbj on January 28, 2020, 03:28:57 pm
Hey vapuser, you bojo! Those boards don't work on water!

Unless you got power! Hahahah...



(http://www.mormonsandscience.com/uploads/8/9/5/6/895673/9252458_orig.jpg)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 05:25:54 pm
Well. I would have to pull the monitor to get a good look at that plug. Maybe this will help. If you still need me to pull the monitor and snap some pics I will do it.(https://uploads.tapatalk-cdn.com/20200128/fb5508ba52ade25b9768f10bdb31d4f3.jpg)

Sent from my Pixel 3 using Tapatalk

Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 05:32:31 pm
Here is a link to the Centipede service manual.

https://www.arcade-museum.com/manuals-videogames/C/Centipede.pdf (https://www.arcade-museum.com/manuals-videogames/C/Centipede.pdf)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on January 28, 2020, 05:53:45 pm
Centipede power supply schematic.

https://www.arcade-museum.com/manuals-videogames/C/Centipede-sp.pdf (https://www.arcade-museum.com/manuals-videogames/C/Centipede-sp.pdf)


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 28, 2020, 06:45:35 pm
Thanks Mike. I do have a copy of the Operation, Maintenance and Service Manual. I also have the electrical schematics of the power supply. I'm just not seeing where to physically plug in that 6 pin male connector. I can see J2, J3 and J5 connectors on the power supply but I can't see where the female corresponding connector is for that male power connector. Do you think it can it be located on another board?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 06:47:02 pm
I am watching a movie with my daughter. I will dig in there after the movie and let you know.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 28, 2020, 07:00:27 pm
Mike, I found the problem. I now remember that I had put a white and black jumper in J2 so that I could test out the power supply. So I removed those jumpers and plugged that male power connector into J2. Now back to my original problem, I still have no power. No lights and no sound. Where to start. Any suggestions?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on January 28, 2020, 07:17:07 pm
Start at the fuse block.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 07:22:11 pm
Start where the power comes out of the wall and figure out where it stops.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on January 28, 2020, 07:47:00 pm
If memory serves...If the top is open it won't work, It has an interlock safety swich.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 07:51:24 pm
Just pull out on the interlock. It will stay on.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on January 28, 2020, 07:59:29 pm
Well ya...but did he?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 28, 2020, 08:09:14 pm
That is why it is good you brought it up.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 29, 2020, 06:26:12 am
Sounds good. I think I'll recheck the voltages from the primary winding at J2 and work my way over to the secondary windings. I did check all the fuses for continuity. they all appear to be fine. I didn't know that you can pull up on the interlock switch to keep it activated. Thanks. I'll keep you posted on my progress.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 29, 2020, 07:08:08 am
It is surprising how many people don't know that. I have pulled that interlock switch trick on people who know way more about this stuff than I do.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 30, 2020, 06:41:30 am
Good morning, Well, as you suggested, I went through and rechecked all the voltages from the power cord to the output of the power supply. I found two bad fuses and replaced them. the original fuses were 7 amp, 250 volt. The closest I could find were 10amp 250 volt. Do you think that the extra 3 amps will put too much strain on the circuit? The output voltages from J5 coming from the secondary winding of the power supply were as follows: Pins 1,5 and 2,5 and 3,5 should read 10.6 VDC. The actual reading was 10.4 VDC. The reading from pins 6 and 76 should be 36 VAC and was 35 VAC. The Reading from Pins 8 and 9 should be 6.1 VAC and actually read 6.2 VAC. The reading from pins 10 and 12 should be 60 VAC and actually read 105.8 VAC which is too high. The other voltages I believe are within tolerance, but that last AC voltage may be causing a problem. Please see attachment. I'm not sure what's causing that problem. Maybe one bad winding on the transformer? More importantly, how can I correct it? I also now need a schematic that shows where those voltages feed into and how to correct that high voltage. Any suggestions?  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 30, 2020, 07:07:45 am
PL1 posted a link to the power supply schematic. The information should be there.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on January 30, 2020, 08:08:26 am
I did the same sort of testing here: http://forum.arcadecontrols.com/index.php/topic,161506.msg1703158.html#msg1703158

You should use the right size fuse.  If you use a 10A fuse and it calls for a 7A fuse..  then the extra 3A the *bigger* fuse allows is the extra 3A to fry your boards (or whatever that particular fuse uses.

The voltage is unregulated - If you want to know much its really putting out - it has to be connected to a load.  I've used 100w lamps as a load to test and check voltages that way..  Big swings are not uncommon.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 30, 2020, 08:13:10 am
Now keep working your way forward until you have no power.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on January 30, 2020, 08:48:05 am
I found two bad fuses and replaced them. the original fuses were 7 amp, 250 volt. The closest I could find were 10amp 250 volt. Do you think that the extra 3 amps will put too much strain on the circuit?
Pull that 10A before you fry something.   :whap

If something is drawing enough current to blow the 7A fuse, over-amping the replacement protects the inexpensive fuse by possibly sacrificing the expensive electronics the fuse was supposed to protect.   >:D

When substituting fuses, it is safe to over-voltage so there's less chance of arcing or under-amp so the fuse blows with less current draw or faster blow-timeNEVER the other way.

The correct fuse values are in the diagram/parts breakdown on pages 47-48 of the manual here (https://www.arcade-museum.com/manuals-videogames/C/Centipede.pdf).


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 30, 2020, 08:56:02 am
It is not difficult to source the correct fuses. There is no point in throwing in the wrong fuse and praying something won't fry.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on January 30, 2020, 11:00:09 am
I would have expected something to pop on at this point. Those two blown fuses were probibally trying to point out your trouble, My guess is one was for the chassis, and more specifically to a bad flyback (given its age) normally if you look at it you will a burnt looking crack in it if it is bad, leak nasty goo, or just be dead, in a dark room like a Tesla coil it may also shoot voltage, In any case approach this with extreme caution (and +1 on changing that fuse back to a 7amp)....Power to the boards test would also be on my list, making sure your getting DC out of that regulator where applicable
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 30, 2020, 02:34:19 pm
Good afternoon, I'll have to order those fuses online. I can't seem to find a place locally that carries them.  I'm sure Amazon must carry them. I'm also going to need the hinged arm that holds up the table top in a vertical position. Is there a place where everyone orders parts from? I might have to fabricate that part myself. So bperkins01, you're thinking I don't have to worry about the 105.8 VAC from pin 10,12. That's good to here. After I replace those fuses, I'll continue through the circuit and try to find where my voltage is stopping. Thanks for everyone's help. I'm determined to get this game working! :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on January 30, 2020, 03:19:57 pm
If you really want to test it to be sure..
Using the info below and the schematic -  Connect a 100w light bulb  to pin 10 and pin 15 from an every day lamp (old fashion incandescent bulb)
Jump pin 12 to pin 13 to put the two 60v windings in series (creating 120v)  (this is exactly what is done in the wiring harness to get 120V to the monitor.

Once your lamp lights up - test the voltages as you did before...  now that there is an actual load ..  it will all test very close to spec (60v, 120v, etc) If there truly is an issue with the transformer - you will see it with this test.
Make sense?

The remaining pins are specific to Centipede
Pin 10 - 11 -> 30 vAC
Pin 11 - 12 -> 30 vAC
Pin 10 - 12 -> 60 vAC

Pin 13 - 14 -> 30 vAC
Pin 14 - 15 -> 30 vAC
Pin 13 - 15 -> 60 vAC
Title: Re: Atari Centipede Cocktail table game has no power
Post by: pbj on January 30, 2020, 03:30:20 pm
It is not difficult to source the correct fuses. There is no point in throwing in the wrong fuse and praying something won't fry.

Ain't nothing frying at 10 amps that wasn't already frying at 7 amps.  You guys are such drama queens.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on January 30, 2020, 03:33:47 pm
Not everybody can be a wildman outlaw like you. ;)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on January 30, 2020, 03:36:47 pm
It is not difficult to source the correct fuses. There is no point in throwing in the wrong fuse and praying something won't fry.

Ain't nothing frying at 10 amps that wasn't already frying at 7 amps.  You guys are such drama queens.

ok - I'll cave on that one..  7A will fry it too..  :notworthy:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on January 31, 2020, 07:19:34 am
bperkins01, I like that idea, but the connector at pin 15 is blank. Is your J5 connector not the same way? So there really is no 60 volts outputted to the circuit across pin 13 - 15 from what I can tell. I never checked the center tap for 30 volts across pin 13 - 14. I just figured that the last 60 volt winding wasn't being used. How about if I use that same positioned jumper, which should give me 90 volts across pins 10 - 14 and 60 volts across 10 - 12. I can check the two additional center taps as well for 30 volts. The incandescent bulb won't be as bright positioned across 10,14 but will still be providing a load. if you think that's a viable solution, I can do all that tonight when I get home from work.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on January 31, 2020, 07:28:50 am
bperkins01, I like that idea, but the connector at pin 15 is blank. Is your J5 connector not the same way? So there really is no 60 volts outputted to the circuit across pin 13 - 15 from what I can tell. I never checked the center tap for 30 volts across pin 13 - 14. I just figured that the last 60 volt winding wasn't being used. How about if I use that same positioned jumper, which should give me 90 volts across pins 10 - 14 and 60 volts across 10 - 12. I can check the two additional center taps as well for 30 volts. The incandescent bulb won't be as bright positioned across 10,14 but will still be providing a load. if you think that's a viable solution, I can do all that tonight when I get home from work.

Unless your Power Brick is different on the cocktail vs. the upright..  you should have a pin on 15.  You need the 2 x 60v circuits to get you 120v for the monitor.
Maybe the pin pushed in?  Take the power brick out and check from the back side..  The links the the schematics and my prior link shows how to look at this..
HTH
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 03, 2020, 06:52:55 am
bperkins01, As you mentioned, the power brick may be wired differently on a Cocktail table model. Maybe someone can confirm that for us. It sure seems that way. Over the weekend, I removed the brick from the game console and recalculated all the AC voltages using a 100w bulb as a load. I also added additional pictures to see the front and back view of the J5 connector to show the missing wires and pins. I also uploaded additional pics to show the front and back view of the J5 plug from the Harness inside the console. I'll also include an updated view of my notes to show the current voltages that were displayed. Just as a recap on the voltages I took were as follows: 1,5 2,5 and 3,5 were 10.4 VDC. The following AC voltages were read using a 100 w light bulb load: 6,7 35.6 VAC, 8,9 6.2 VAC, 10,12 102.5 (Too high, should be 60), 10,14 123,8 VAC. See pics for a detailed view of the connectors.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 07:00:04 am
Stop chasing your tail verifying voltages.

Measure where you have power. Work your way forward until you don't have power. That is where your problem will be.

It is odd that you don't have any power at all. It almost has to be a fuse.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 07:50:10 am
You can also work the other way. You know where the power is supposed to end up. Start there and work backwards.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:13:56 am
First Q:
I went back and read your original question:
The 6 pin connector - J2 - is where the interlocks plug in - If you have nothing plugged into it - that's your problem.. The connector is hiding inside your cabinet someplace.
Did you find that?

Second:
Your transformer is different than mine,  I'm betting the 102v is also fine..  Maybe its an ARI and not an ARII.  I'd have to go look at other schematics

Either way
Whats the answer to Q1?


Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:14:46 am
If he traces his way backward he will find it.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:15:39 am
If he traces his way backward he will find it.
Agreed :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 03, 2020, 08:41:04 am
That wire nut looks suspicious to me, those were usually crimped, and would expect to see a grommet or something there, somebody has done work...I would take a closer look in that area.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:45:41 am
Mike, I found the problem. I now remember that I had put a white and black jumper in J2 so that I could test out the power supply. So I removed those jumpers and plugged that male power connector into J2. Now back to my original problem, I still have no power. No lights and no sound. Where to start. Any suggestions?

It looks like J2 goes to the interlock switch and the power switch. Both of those could cause no power to flow to the rest of the cab.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:51:55 am
Mike, I found the problem. I now remember that I had put a white and black jumper in J2 so that I could test out the power supply. So I removed those jumpers and plugged that male power connector into J2. Now back to my original problem, I still have no power. No lights and no sound. Where to start. Any suggestions?

It looks like J2 goes to the interlock switch and the power switch. Both of those could cause no power to flow to the rest of the cab.

I missed that - so the mystery of J2 has been solved :)

Jennifer - the wire nut part is where a panel mount fuse holder should be - that would also kill power to everything if that was screwed up.  But not likely since power has already been measured down stream.  (However - I'd get the proper holder and return it to normal)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 03, 2020, 02:09:39 pm
The mystery of J2 was solved long ago. Also there is a proper fuse holder where the power comes in. All is good there as well. We're at J5 now where the voltages don't match up to the schematic. Did my 7 pics that I uploaded this morning not show up? 10,12 is showing 102.5 VAC, should be 60 VAC. Pins 11 and 13 are blank, no wires or metal pin. Pin 15 on the underside of the power supply has a green wire that is fastened to the chasey. I wonder if there is anyone out there that could verify these pin configurations. This game did work properly at one time with this configuration. I'm still thinking that a winding on the transformer went bad.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 02:17:59 pm
The mystery of J2 was solved long ago. Also there is a proper fuse holder where the power comes in. All is good there as well. We're at J5 now where the voltages don't match up to the schematic. Did my 7 pics that I uploaded this morning not show up? 10,12 is showing 102.5 VAC, should be 60 VAC. Pins 11 and 13 are blank, no wires or metal pin. Pin 15 on the underside of the power supply has a green wire that is fastened to the chasey. I wonder if there is anyone out there that could verify these pin configurations. This game did work properly at one time with this configuration. I'm still thinking that a winding on the transformer went bad.  :)

There is a single pic of the underside of the power brick.. that's it.
you see what we see on the thread.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 02:24:13 pm
When I get home from work I will measure some voltages for you on my machine. If you are getting voltage at J5 your monitor should be receiving power. I think it is pin 10 and 15. I will double check that when I get home.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:17:39 pm
Here is what my original schematic says.

(http://forum.arcadecontrols.com/index.php?action=dlattach;topic=159740.0;attach=381241;image)

Pin 10,12 should be 100VAC

11 and 13 are blank.

pin 15 is earth ground.


Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:41:32 pm
Odd the cocktail has such a different power supply - but that mystery solved too!
Nice   :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:45:30 pm
I should have dug my original schematics out sooner.(https://uploads.tapatalk-cdn.com/20200204/fa2737f394d014a1839b54c59ee315c6.jpg)

Sent from my Pixel 3 using Tapatalk

Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:46:59 pm
hmmm beer...
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:52:58 pm
There is a visceral feeling when you unfold the schematics and spread them out over a table. Same thing with flipping through a manual.

It seems a little sad that the younger folk will never know that feeling.

Maybe they are not missing anything. :dunno

I prefer the treasure map feel of the experience.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 03, 2020, 08:54:36 pm
well ya!  I thought I downloaded everything Centipede - but the one you have is different.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 03, 2020, 08:59:23 pm
I never had to dig into it. My cab is a B or C in outward appearance, but it has been electronically trouble free.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:14:40 am
I'll try to upload those pics again. Maybe I'll try just one at a time. The text post that I included with those pics didn't go through either. Strange. Here is the Male plug on Harness.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:16:22 am
Here's my notes on the Connector with Updated voltages.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:17:46 am
Here's a pic of the J5 female connector from on top of the Power Supply.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:19:06 am
Here is a pic of the J5 Female Connector from underside of the power supply.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:20:27 am
Here is a pic of the J5 Male connector plug inside the game console.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 04, 2020, 06:20:45 am
Reply 44 answers your questions about J5.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:22:18 am
Here's a pic of the J5 Male wire side of the connector.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 06:36:12 am
Before I go any further through the circuitry, I would like to establish that these are the correct voltages that I need to supply all the electrical components. And so far, according to the schematic, it appears that my voltages are off. I'm surprised that there isn't anyone with a cocktail table that can confirm what I have so far is correct or not. Frustrating.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 04, 2020, 06:50:40 am
Before I go any further through the circuitry, I would like to establish that these are the correct voltages that I need to supply all the electrical components. And so far, according to the schematic, it appears that my voltages are off. I'm surprised that there isn't anyone with a cocktail table that can confirm what I have so far is correct or not. Frustrating.

MikeA answered this in reply#44 - Your 100v is correct.
The cocktail version of Centipede has a different power brick (and schematic) than the upright - that explains the variations from the other power bricks.

I went back and looked at your numbers -  at this point - your issue is not in the power brick. 
Schematic shows 10 - 12 = 100v,  10- 14 = 120v

If you have no power to ANYTHING with it plugged in to the game - I would try not plugging in the 6 hole connector to your harness and keep it on bypass.  You may have an open circuit on the interlock switches..  which would mean - nothing worked..
Make sense?







Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 09:19:30 am
Thanks bperkins01, Sounds good, I'll hook up the brick back in the console and leave the two jumpers in J2 to bypass the switch. I'll check it out again tonight when I get home and give you an update tomorrow. Thanks again for your help. :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 04, 2020, 09:21:14 am
Thanks bperkins01, Sounds good, I'll hook up the brick back in the console and leave the two jumpers in J2 to bypass the switch. I'll check it out again tonight when I get home and give you an update tomorrow. Thanks again for your help. :)
and MikeA - he had the correct schematic - but you should be on the right track. 
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 04, 2020, 12:37:07 pm
Mike, thanks for that schematic. That is the one I should have and don't. Is there a link to that somewhere? Very helpfull!!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 04, 2020, 12:43:03 pm
When I get home from work I will take a bunch of pics and upload them here.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 05, 2020, 06:50:28 am
Good morning all. Well, I installed the brick back into the console. I left the jumpers in J2 to bypass the interlock switch. I still have the same power to J5, but when I put the coins in the game, no lights, no sound, no life. I need to continue to trace out the circuit. As soon as Mike uploads more schematic pics, I'll keep working upstream. Maybe next I'll check out the voltages at the coin receptor. Not sure if that's the next logical check point. I wonder if there are any other fuses that I'm not aware of, other than the ones on the PS. I feel that I should be seeing or hearing something. Again, thanks for all you help!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 05, 2020, 07:06:30 am
Since J5 has power, check for power at the monitor plug next.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 05, 2020, 07:52:51 am
Good morning all. Well, I installed the brick back into the console. I left the jumpers in J2 to bypass the interlock switch. I still have the same power to J5, but when I put the coins in the game, no lights, no sound, no life. I need to continue to trace out the circuit. As soon as Mike uploads more schematic pics, I'll keep working upstream. Maybe next I'll check out the voltages at the coin receptor. Not sure if that's the next logical check point. I wonder if there are any other fuses that I'm not aware of, other than the ones on the PS. I feel that I should be seeing or hearing something. Again, thanks for all you help!
What Mike said - but the power supply - supplies a few different circuits - that's why there are a few voltages.. Monitor, board, lights on the coin door, etc..  If nothing at all is showing life - its *sounds* like your ground wire is detached someplace - probably close or at the J5 connector.  Tug at the wire at the connector and down stream of it..

Many voltages out - one ground wire back.  (except the monitor - its on its own)

Continuity on the ground wire is easy to check with a meter.. 
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 05, 2020, 12:08:15 pm
Ok, I May not be able to check tonight again but I'll check that chassis ground for continuity tomorrow night. Thanks. :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 05, 2020, 10:42:19 pm
(http://forum.arcadecontrols.com/index.php?action=dlattach;topic=159740.0;attach=381259;image)

I hope this helps.

If you need a higher res image, PM me your email address. I will send you the full res file.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 06, 2020, 04:08:35 pm
Yep, Mike, I actually flip that bottom switch on and off instead of unplugging from the wall. Anxious to see the full res file. I'll check the green grounds as well as the voltages at the coin receptor. I have a two player receptor. I don't see the voltages on the schematic for that plug. When I put the coins in, they just fall right through to the box below. I forgot if that's the way it's suppose to work, or is that because there is a lack of voltage at the plug going to the mechanism. It's been a while since I played on this game. I can't remember.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 06, 2020, 04:17:32 pm
Coins will fall straight through until the game is powered up and ready to accept coins.  Its a pretty smart mechanism.  There is a small solenoid that the PCB tells to engage when the game is ready.  That way it doesn't take a quarter when its powered off.

You should be able to test for power with all the info you have however.. Just work you way out from the power supply...
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 10, 2020, 07:51:10 am
Good morning all, Mike, thanks for that schematic image! huge help. Well I did more testing over the weekend. I started by creating some notes of the wiring harness to get a visual idea of the flow of things. See attachment. I first starting testing the power at the monitor's 3 pin connector. The voltage was 126.6 VAC. I also checked the voltage at the monitor's 6 pin plug - No Voltage. I continued to check the voltage at the coin mechanism. The voltage across pins 10 and 11 was 6.3 VAC. No other voltages at that plug were present. I also took apart and viewed the connectivity of the volume control, Self Test switch and the Coin switch. All seemed to be working fine. I don't know why the coin switch is a momentary type switch, wired in the (Normally Opened position). I'm not sure what that switch does. When I was checking out those switches I noticed that the ground wire from there was loose. So I cleaned the eyelet and tightened the screw. As I've been checking through the circuitry, I haven't noticed any other loose ground wires. Still no life. I'll continue testing.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 10, 2020, 08:05:04 am
Still sounds like a bad ground connection.
You have voltage everywhere and nothing works.
I'd check the wiring harness for continuity from the first ground wire each step along the way..
ie.  Positive power is getting all the way through the wire - but is getting stopped on the return side.

Clip one lead of the meter to a known good ground (post with green wire on power brick)
The test for continuity to everything else - starting at pin 4-5 on the power supply connector, then the ARII board, etc..
Your likely to find an open circuit very early - between the Power supply/ARII/PCB - since after the PCB most of the power fans out.
Do this with the power off on the machine.

fyi:  the 6 pin connector for the monitor is the video wire (the HDMI connector of 1981)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 10, 2020, 08:21:41 am
If you have power to the 3 pin monitor plug then it is time to follow that power to where is stops on the monitor chassis. Hopefully it is a fuse. I will check my monitor schematic when I get off work today.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 10, 2020, 08:33:01 am
Maybe I missed it along the way...
Is EVERYTHING dead? or just the monitor? 

Just to catch up - is Anything working?  or is the entire machine a brick.
Is the power LED on on the PCB?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 10, 2020, 08:39:46 am
You are getting power at the coin door. Are you saying that the coin reject lights are dead?

If so, are the bulbs blown?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 11, 2020, 06:49:54 am
Good morning all, I wanted to start this morning by answering all the above questions. regarding bperkins01's concerns, I started checking all the ground connections for continuity. I started from pin 4,5 on the p.s.(J5) connector. There is ground continuity at that point. I checked all these ground locations by clipping a 2 foot jumper cable to the p.s. chassis and connecting the meter to the other end of the jumper. I also pulled out the Regulator Audio PCB and checked the P10 plug and P6 plug. Both grounds at those locations are good. The interlock ground is good as is the ground at the Dual Coin Mechanism. I also didn't want to assume that the ground connection from the wall Receptacle was good so I checked that out as well. Then at connector J4 (from the AC outlet) I put my volt meter across pins 2,1 (Ground and black) to verify that I was getting a voltage, which I was. So It appears that all grounds so far are all good. I couldn't find the ground at the PCB board (J20), but I'll look again tonight. Speaking of the PCB board that LED light is not lit. So it does appear that everything is dead including the monitor. I am getting power at the coin door (6.3 VAC across pins 10,11). But no lights. So I took the coin mechanism out of the chassis and checked the bulbs. One was blown and the other one was questionable. So I went on Amazon and ordered a pack of those 6.3v .25a mini indicator bulbs. While I had the coin mechanism out I also checked the two mini switches. Those were working fine as well. I reassembled everything and scratched my head some more.  :dunno I'll continue checking voltages at the regulator and see If I can find that ground connection at J20.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 11, 2020, 07:38:32 am
If you have power to the 3 pin monitor plug then it is time to follow that power to where is stops on the monitor chassis.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 11, 2020, 07:52:23 am
Hmm.
On the PCB there are a number of test points:
+5v  <- Most important one  if you don't have this - that is why the PCB is dead
-5v
+15v
-15v
+22v (unregulated - it will likely be 22-24v range)
-22v (same)
-30V

If you have no LED on the PCB - see if anything is getting to it at all by checking these test points.

On the ARII there are a similar set
-5v
+12v
+10.3v  (Unregulated)
+22v UR
-22v UR

36v AC  (this one is trickier - you have to use both probes on both 36v connections and your meter on AC)

The 2N3055 bottlecap transistor in the center of the large heatsink is a known troublemaker and creates all the power.  If your voltage test points on the ARII are all screwed up.  It's likely that.

I literally did all of this last night on my machine (Centipede upright)
The -5v Voltage regulator on my ARII was dead (Had one of those and replaced it - except I'm not certain it actually does anything  I just found it - its part of the audio circuit.  The very first time I played it the volume did a few weird things after the game warmed up..  So maybe that's fixed too.)

The +15V regulator was dead on my PCB - It is part of the high score retention circuit. Waiting for one of those to come, and I had issues with it..

You've checked the power brick - next layer on the voltage front is ARII - then test points on the PCB.. 
Coin door lighting comes of the ARII - not the PCB

Finally - what MikeA said - if you are getting nothing to the monitor - need to test voltage into it and check the fuse..  The CRT is pretty much a stand alone circuit.

Keep digging...




Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 11, 2020, 08:02:40 am
Can you snap some pics of the PCB? Both sides. Especially the edge connector.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 11, 2020, 09:49:02 am
Mike, can I safely remove the two connectors (J19 and J20) from the PCB board before sliding the board out? It seems last time I tried removing those connectors, they felt like they were on there pretty tight. I'll take the pics tonight when I get home.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 11, 2020, 09:59:32 am
anything that plugs in can be unplugged.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:21:18 am
Good morning all, Well, last night I took a reading of all the "test point" voltages on the ARII board. Here is the first sign of where the voltages stop. From the board I'm missing the 10.3 VDC. The good news is that the other 5 voltages are good. The 36 VAC, +22VDC (Actual 24.6), -22VDC (Actual -24.5), 12VDC and -5VDC, all good! See pic below "ARII Voltages from board". What's strange, is that I'm missing a lot more voltages from the plug connectors on the board. Does that make any sense? There are no voltages from the P7 connector and no voltages from the P10 connector. The only voltage I'm getting is from connector P9 36VAC (Actual 36.5). See pic below "ARII Voltages from connectors". I'll have to look back on the schematic to see where those connector voltages are coming from. What do you think?

I didn't have a chance to check any test point voltages on the PCB board but I did take a few pics of the board for Mike. I forgot to take a pic of the back of the PCB board for you. I'll do that tonight as well as check all the test point voltages. I did notice that there was a jumper wire soldered across a short length of circuity on the back side. Looks like there may have been problems in the past with the board. If I hold the board up to the light, all looks pretty good except for that one spot they bypassed with the jumper. Check out all the pics below. I'll report back tomorrow morning with additional readings.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:22:40 am
This pic shows the voltages from the board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:24:12 am
This pic shows the ARII voltages from the connectors.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:26:18 am
This pic below shows the front view of the ARII board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:28:03 am
This pic below shows the back side of the ARII board. Shows a lot of age but all the connectivity appears to be fine.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:29:28 am
The pic below shows the full view of the PCB board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:31:08 am
This pic below shows the pins J19 and J20 of the PCB board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:32:41 am
This pic below shows the middle of the PCB board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 12, 2020, 07:36:27 am
This pic below shows the bottom of the PCB board. Do you happen to know what that Reset button at the bottom of the board resets? It also look like another connector at the bottom of the board. I wonder if that's used for test connection of some sort. There was no connection to it inside the console. Any ideas?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 12, 2020, 07:53:04 am
Well - all your problems (for now) are on the ARII board.
I've been advised to pretty much always replace Q3 - 2N3055.  It runs the hottest, does the most work and is most likely to fail.  If you notice runs all of the +5v circuits that feed the PCB.
There are many youtube videos on transistor testing and I'd target that one to see if it shows bad - then replace it anyway.

After that - the LM305 is the next likely part to be bad causing no +5.
https://www.arcadepartsandrepair.com/store/integrated-circuits/voltage-regulators-integrated-circuits/lm305ah-voltage-regulator/ (https://www.arcadepartsandrepair.com/store/integrated-circuits/voltage-regulators-integrated-circuits/lm305ah-voltage-regulator/)

When I ordered my 2N3055 - I got a LM305 and put it on the shelf (shipping savings).  You should get both from above.  Word has it there are many crappy Chinese ones and you want a good one.  (no personal experience honestly - but I agree with the sentiment).  If you replace that - you will likely be back in business.  Good digging!!

It took me a while to realize there are *many* power supplies inside this machine - not just a power cord in and lots of outputs.
(ex: the -5v comes from a small voltage regulator chip, on the PCB +15V comes from yet another voltage regulator chip)
Getting very close...


Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 12, 2020, 07:56:27 am
Now we are getting somewhere.

Get that AR II functioning. If it is too difficult there is a guy on KLOV that fixes them and sells them.

bperkins has done a lot of work on his Centipede. Follow his advice. It will be cheaper and more satisfying if you complete the repairs.

You are doing a good job so far. Keep up the effort.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 12, 2020, 12:55:27 pm
I dont know about satisfying it could be, I got holes burned in all my dresses, got fried my hair one day, burnt fingers, Late night sleepless stress if something goes wrong if it doesn't work.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 12, 2020, 12:56:46 pm
Is there a sentence somewhere in that mess?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 12, 2020, 01:05:36 pm
Nothing better than fixing something that doesn't work - yourself.  Especially if its something you enjoy. 

Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 12, 2020, 07:01:52 pm
Guess I really dont see it as a satisfaction thing, It is a job that needs to be done, or the alternative is sit and look at it and just dream about doing it someday...Either way not really a top shelf ego boost.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 13, 2020, 07:13:19 am
Good morning all once again. I feel we're getting close. As I posted yesterday, I would take pics of the backside of the PCB for Mike. Mike please see below. Also here are the test point voltages of the PCB:

Required Actual
voltage   voltage
+5v        0v
+22v      +24.3
-22v       -24.4
-15v       -14.9
_15v      +15.4
-30v       -27.6
-5v         -5.1

Yesterday I ordered the (Q3) 2N3055 Transistor and  the (Q1) 5v Linear Voltage Regulator. bperkins01, did the transistor come with the heat sink compound or a gasket? Or did you have to order those parts separately? I will definitely be installing these parts myself. I agree! Nothing better than fixing it yourself. It must be a guy thing. I watched a couple video's on the installation. One guy used a GS Silicon heat sink compound on a formica type gasket. The only kind of heat sink compound I've used was applying a CPU chip in a motherboard. I don't think the compounds are the same. Not sure. I heard that some compounds can cause a capacitance. See: https://bestthermalpaste.com/thermal-paste-vs-thermal-grease/ Any knowledge on the subject? Are the above voltages what you were expecting to see? I'll report back tomorrow. Have a good day.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 13, 2020, 07:16:15 am
PCB Backside top of board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 13, 2020, 07:27:43 am
Mine came with a gasket.  Just a little thermal paste - don't worry beyond that - its just to help the heat dissipate.  I even think there was a little packed of paste..  (Can't remember now) but it takes slightly  more than a smudge of goo.

No +5V explains a lot..  since the PCB board does all the thinking and the CPU needs the +5v to think.

Mine had no -5v, no +15v and no -30v

-5v is on the ARII  (replaced power regulator)
+15v is on the PCB (replaced power regulator)
-30v is on the PCB - which I thought was not there because of the +15v - BUT - it turned out that I needed to replace the 555 timer chip..  which somehow takes the -15 and +15 and makes +30v..   which then feeds the high score retention chip  (which my pcb did not retain high scores)

I just did the 555 last night - but haven't tested the high score yet - monitor was apart on the bench..  but I'm 99% sure it will work.

You look to be in good shape - until the next item down stream is broke - but good digging!!
Now the hard part... waiting
 :applaud:

Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 13, 2020, 07:29:39 am
The +5 0v is why your PCB is not responsive. You and bperkins need to get the ARII functioning correctly. That should get us power to the PCB.

Hopefully the PCB is fine and just not getting the power it needs right now.

If you have down time waiting for parts, you could check any fuses on your monitor chassis. With power to the plug that monitor should be firing up.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 13, 2020, 07:31:38 am
The +5 0v is why your PCB is not responsive. You and bperkins need to get the ARII functioning correctly. That should get us power to the PCB.

Hopefully the PCB is fine and just not getting the power it needs right now.

If you have down time waiting for parts, you could check any fuses on your monitor chassis. With power to the plug that monitor should be firing up.

Agreed  - the monitor stands alone.  You should hear it start..
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 13, 2020, 07:31:54 am
Also, your edge connector contacts look okay in the pics. You might want to take a good look at them and make sure they are clean.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 13, 2020, 07:38:37 am
While we're spending all your money...
https://www.amazon.com/gp/product/B079YVJHG3/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B079YVJHG3/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1)

This thing is excellent - I wish I knew about them years ago..  use it like a pencil eraser to clean contacts.  I've needed this for 30 years..
Just used it last week because the TV remote wouldn't charge right...  cleaned the contacts
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 13, 2020, 07:42:17 am
Yeah. Those work surprisingly well for arcade PCBs.

It is easier than chemicals and a stiff toothbrush.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 13, 2020, 12:20:00 pm
Mike, Like you said, I think while I'm waiting for parts to come in, I'll look at the monitor again. I believe that the 3 pin connector was supplying 126.6 VAC. The 6 pin monitor plug had no voltage at all. Does the connector supply voltage to the monitor or do the components on the monitor supply voltages to the plug? I did notice a fuse way up underneath the monitor. I'll try to remove it and test it for continuity. Do you think I should remove the whole monitor from the chassis or should I try testing from underneath? I'm not really sure what I'm looking for. Other than that fuse which visually looks good,  :dunno I don't know. You mentioned that this monitor circuitry was totally separate from the rest of the boards. So then replacing the components on the ARII won't supply voltage to that 6 pin monitor plug? Just a thought. What are your suggestions?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 13, 2020, 12:21:31 pm
That yellow lettering says "No power at all". Sorry about that.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 13, 2020, 12:37:34 pm
The six pin connector provides the video signal from the PCB to the monitor. That is not a concern at this moment. the 3 pin plug supplies power to the monitor. When there is power there the CRT should do something. I would suggest looking up CRT repair and safety on youtube. You need to learn where the high voltage is hiding and how to properly deal with it. You need to learn the basics before you dive in.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 13, 2020, 12:39:04 pm
There is a 6 pin connector with thin wires..  that is your RGB connector.  It has no power because of no +5V and isn't relevant at the moment.

there should be a 2 or 3 wire connector off the harness that is very similar is size to an everyday extension cord.  It will have 120V - which we know works directly off the power brick  (its not off the ARII)

There is a fuse on the CRT itself right where the power connects..  its likely a 3A - 250V fuse.
Focus on that power line into the CRT..  if it has power (and it does) then I'd pull the CRT to check the fuse..  I'm guessing you can't see anything while its in the cabinet.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 13, 2020, 12:39:47 pm
The six pin connector provides the video signal from the PCB to the monitor. That is not a concern at this moment. the 3 pin plug supplies power to the monitor. When there is power there the CRT should do something. I would suggest looking up CRT repair and safety on youtube. You need to learn where the high voltage is hiding and how to properly deal with it. You need to learn the basics before you dive in.
Great minds  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 13, 2020, 09:30:50 pm
Sitting around waiting for the mail man will just make you old...Grab a switcher, or a benchtop P/S and continue troubleshooting.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 14, 2020, 07:02:36 am
Good morning all, just a quick update before the weekend. My fuses came in as well as the miniature bulbs for the coin receptor. I put all the new parts in and took a few pics of the monitor. I probably won't remove it from the chassis until after I replace the transistor and the regulator in the ARII. As you can see from one of the monitor pics below, a zoomed in view of the fuse looks like it might be ok. Won't know until I actually test it. There is another pic that is showing what looks like a bad electrical component. I'll have to look that number up in the parts list. I was reading an article yesterday on how to switch out an old CRT with a modern LCD. Has anyone tried that? Any pros and cons? Well, have a good weekend, I'll check back on Monday.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 14, 2020, 07:05:37 am
This pic below shows the fuse.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 14, 2020, 07:11:01 am
This pic is showing what appears to be a bad part.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 14, 2020, 07:39:43 am
Do not put an LCD in that cab. Please God no.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 14, 2020, 08:18:09 am
LCD,  All new, and minty! (Jennifer amused at the prospect) ...Yes that is a bad part all right, the way it is weld spattered My guess that flyback is bad and melted it with a voltage arc (pretty much what I said way back at the beginning of this thread)...You are going to have a big pile of DIY satifaction into this by the time you also do trans/caps...Carefull messing around with that width coil they can be hard to find and or replace...America's sweetheart has left the building.👸
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 14, 2020, 08:29:54 am
If it comes to the nuclear option you can have the chassis fixed or replaced.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 14, 2020, 09:26:22 am
If it comes to the nuclear option you can have the chassis fixed or replaced.
That's the "DIY job well done satifaction" I am missing out on? Just pay a guy?...Omg, I laughed so hard, I may have pee"d a little...Drink a Creme flavored soda throw it on the workbench, and just fix it like a girl...Omg, so funny.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 14, 2020, 09:28:29 am
That is why it is the nuclear option you turd. If he is overwhelmed and considering an LCD than I am offering a better alternative.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 14, 2020, 09:41:29 am
Fixing PCB's and replacing low power chips is one thing - I can certainly understand not wanting to poke around inside of a CRT (I am - but that's because I want to learn how to fix them)

Vapuser - Please don't put in an LCD..  just because...
if you are liking fixing the primary machine (and it seems like you are)
then figuring out what that chip is (and I'm going to guess its a voltage regulator...  It seems like its always a voltage regulator...)  then maybe look into replacing it.

Here is what I've learned on CRT's  - If you are nervous - discharge the tube (while not plugged in) and you will be fine..  that's it. Lots of videos on this.

There are plenty of guys that can fix them too...

My Analogy:  I can fix pretty much anything on a car..  I've even rebuilt a couple engines..  But if there is an issue in the automatic transmission - that goes to an expert..  Experience counts on those..  to much can go wrong.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 14, 2020, 10:09:04 am
While still amused...You guys are not wrong, A problem monitor bites hard, and can understand where some might just draw the line at the prospect...Problem is those monitors have lived past there designed years and are developing problems not covered in your traditional fix it shop, And most of the techs, are either long retired...or no longer with us.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 14, 2020, 10:43:09 am
So funny, I didn't realize the mention of the word LCD would cause such a ruckus. I have no intention of converting this over to using a LCD screen, I just wondered what your thoughts were on the subject. If you guys feel this monitor is salvageable then I'm on board. If that part is a voltage regulator chip, I'll order a new one and put it in. If we find other parts that may need replacing, then we'll replace those as well. That bad regulator chip kinda makes sense as to the lack of voltage at that 6 pin connector. Maybe that's the problem with this monitor. As far as your "Analogy" above, I use that same analogy all the time. If we get to a point where I feel this is way over my head, then I'll reach out to a repair guy. So far, I'm enjoying this, So lets continue on.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 14, 2020, 10:50:01 am
Well then - next step - pull the CRT.
What model# is it?
I'm pretty sure its a regulator chip - but its a guess.

If you want to really kill some time - https://www.youtube.com/watch?v=dDe13pesba4
there are 4+ hours of these videos - I've watched them twice..  Very good in understanding whats happening..
My Centipede monitor has issues and I've worked through most (but not all) of them..

If you want to dig into CRT repair - Its a good place to start. 
He talks a lot about the hardest working chips, etc..    Big power transistors and voltage regulators are the common failures.


Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 14, 2020, 11:32:01 am
LCD monitors in arcade machines make me slightly homicidal.

I am really glad to see you working hard to restore this machine.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: pbj on February 14, 2020, 01:24:45 pm
I'm genuinely surprised Randy Fromm is posting those videos on youtube.  Either he's turned a new leaf or decided the cat's already out of the bag.  I remember the days when he would bid up the auctions on Ebay just to keep his stuff from going too cheap....

Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 14, 2020, 01:34:38 pm
They are on his own channel - the videos are older than dirt..  But the info is very good. 
as a result....

I emailed him, thanked him for the videos and let him know they generate revenue..  I ordered his Big Blue Book - which I hear is a great resource in general.
After watching nearly 20 hours of video - the cost of the book was easy to justify.

He responded to my email within 10-15 minutes..

Title: Re: Atari Centipede Cocktail table game has no power
Post by: pbj on February 14, 2020, 02:50:41 pm
They were older than dirt 20 years ago and he was still bidding those auctions up to $400....

 :dizzy:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 14, 2020, 04:15:07 pm
They were older than dirt 20 years ago and he was still bidding those auctions up to $400....

 :dizzy:
Does anyone do that anymore?  bid up their own stuff? 
I just buy it it now on eBay... I don't think I've bid in 10 years.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 10:47:53 am
Good morning all, It's Saturday morning and I just installed the Q3 - 2N3055 Transistor and the 5v Linear voltage Regulator. After doing a little drum roll and then pulling up on the interlock switch, I saw the LED on the PCB come on for a second and then went out. I took the ARII board back on the bench and rechecked the solder connections. I found one pin on the regulator that was questionable and re-soldered it. Before reconnecting the board and turning the power back on, I checked the fuses. I noticed that the two 7A fuses blew out. I replaced the two fuses, plugged the ARII back in and turned the power back on. Exact same thing. The PCB LED came on for a second and went out. I again checked the fuses and noticed that the same two 7 amp fuses blew out again. I wonder what is causing the short? Here I thought I was going to be making progress. Any thoughts? :( 
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 15, 2020, 11:00:39 am
Is the power coming from your wall bad? Is your plug wired correctly?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 15, 2020, 11:02:50 am
There isn't much in front of this fuse to go wrong.(https://uploads.tapatalk-cdn.com/20200215/eeb6ed9a36d22bcd002df9541de3179e.jpg)

Sent from my Pixel 3 using Tapatalk

Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 15, 2020, 11:05:15 am
Or are these the problem?(https://uploads.tapatalk-cdn.com/20200215/6940ce0b3645c084c1d90d48e5a18882.jpg)

Sent from my Pixel 3 using Tapatalk

Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 15, 2020, 11:12:34 am
I am going to pull the monitor on my centipede so I can get a clear picture of what is going on. I can't do it until at least tomorrow though.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 11:26:31 am
First - unplug the PCB - until you find the short - don't have it plugged in at all.

I'd be inclined to put a fuse in with nothing connected to the power brick and make sure it doesn't blow.
Then add the ARII and see if it blows..  (w/o the PCB)
The CRT comes off that too - did you do it with the CRT plugged in?  Because that would make a lot of sense..
do it w/o the CRT..
If it doesn't blow..
then add the PCB (no crt)
If I were staring at it myself..  I'd poke all the way through it with the meter looking for the short.. 
But at a high level..  it would make sense if it blew with the CRT plugged in based on the pad voltage regulator.
Curious to know what you find



Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 15, 2020, 11:52:52 am
Fuses can get quite expensive if your just going to throw them in the trash, Wiring in a 7 amp circut breaker while testing is a good alternative (Around 12.00 I believe) ...And like b/perkin says, break it down to basic string and protect the board, only hook that up when everything checks out...More than likely your problem is that chassis, more specifically the flyback, and as consequence regulator and transistor...But what does Jenn know🙄
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 15, 2020, 11:57:43 am
Jenn knows more than I do, but you have to catch her before she starts smoking meth.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 15, 2020, 12:01:57 pm
Funny man...The fact you are willing to pull your monitor out for this guy, says alot about your character 😘
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 12:22:45 pm
Ya know, now that I'm thinking about it, I bet this has been the situation from the beginning. If you remember, back in the beginning of this thread, you suggested to first check all the fuses. I mentioned that the two 7 amp fuses were blown and I replaced them with 10 amp fuses that I purchased at the hardware store. I thought that I would leave those in until my order of 7 amp fuses came in the mail. Not realizing that those fuses blew immediately as soon as I turned the power on. I just now checked them and sure enough, they're toast. So when the fuses came in the mail the other day I replaced those 10 amp fuses (which I thought were still good), with the 7 amp fuses. Then before turning the power on, I replaced those parts on the ARII and turned the game on for the first time with fresh fuses in place. All the while, keeping my eye on the PCB LED. And that's when I noticed that the LED came on for a second and then immediately went off. Also realizing that the 7 amp fuses were blowing immediately! Mike, I checked my receptacle outlet when I started to check all the ground connections. Remember, I didn't want to assume that the receptacle was wired correctly. Oh, by the way, the bulbs for the coin mechanism also came in and work perfectly. It's nice to see that at least those lights turn on when I turn the machine on. So bperkins01, I like your idea above, I'm going to go try that now. I'll let you know what I find. Oh crap, I'm out of fuses. Looks like I'll have to order more. Jen, I like your idea about a 7 amp circuit breaker. I'll have to put one together. Thanks!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 12:47:52 pm
Was your CRT plugged in when the fuses blew?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 02:17:36 pm
Actually - thinking through it... 
It's probably not the CRT - because its on the isolation side of the transformer.

Looking on that side of the transformer for 120V:
- Interlock switches
- J4A for marquee lighting (Does the cocktail even use this connector?)
- Yellow voltage selector wire block
- EMI Filter..

You tested with the interlock switches connected - My hunch is since everything worked properly with the testing jumper in place.  You may have a short in one of the interlock switches.   If you look at their schematic - they are double pole double throw.  A short there would explain what you are seeing..

Easy to test for short with a meter.
 - or -
Disconnect everything from the power brick - put any fuse in the 7A socket (it won't matter for this test) - connect the interlock switches and turn them on/off  - if the fuse blows - then you found the short...

Make sense??





Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 03:36:52 pm
bperkins01, I found two 6 amp fuses in one of my drawers and put those in the fuse socket. I did this before I read your last post at 02:17. I disconnected the CRT, ARII and PCB. I then plugged in the game, turned on the bottom switch and while watching the two "Fast blow" fuses, I pulled up on the top interlock switch. As soon as I did that, the fuses blew instantly. Ya know, now I'm not sure if everything was working properly with the testing jumpers in place. Maybe those fuses were already blown at that point. Anyway, I'll go pickup a couple more fuses at the hardware store and test those two dpdt for a short with my meter. I'll let you know once I do that.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 03:46:05 pm
I have a feeling its one of the interlock switches - test it with them bypassed and then with them connected.
or best with a meter of course to save fuses.
I think you are close...
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 04:26:23 pm
It seems I remember early on testing that bottom switch. I wanted to know which way was off and which way was on. Well I got back from the hardware store and luckily they had 7 amp slow blow fuses. So I bought the last three packs they had. I'm going to try to do all the testing with the meter to save the fuses. I'll get back to you when I'm done. :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 05:44:16 pm
Well, I did all the testing with my ohm meter at the J2 connector. I pulled up on the top interlock switch and turned the bottom switch on. I should be getting continuity across the two white wires and across the two black wires, which I am. I'm not getting any continuity across white and black which would indicate a short, correct? When I turn off the bottom switch, I'm not getting any continuity across any pins, which I shouldn't. Just for the heck of it, I checked for continuity across the two orange wires coming from the transformer. Each of those wires goes to a 7 amp fuse at F2 and F3. I'm getting continuity, which I don't think I should. right? Isn't this indicating a short across the secondary winding from the transformer? What do you think?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 06:01:59 pm
Another thing, before I joined this forum, the first thing I did was I replaced the big blue cap and also put in a bridge rectifier. I'm not sure I should have put in that bridge rectifier in. You gotta remember, I was working off of a schematic that should a bridge rectifier configuration instead of the one that Mike sent at reply 131.I wonder If I screwed things up by doing that. Or are both configurations accomplishing the same thing by changing AC voltage to DC voltage. I'm just trying to make sense of all this. Anyway, the two switches appear to be working fine. Not sure what to look at from here.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 06:13:31 pm
I would disconnect the interlock switche harness completely and put it back in bypass.
On the 7A fuse side of the primary transformer - there is nothing except what I outlined earlier.
Plug in a fuse and see if it blows..with nothing attached and in bypass.

You are down to the EFI Filter (which should never die) or a bad primary winding.
So hard to diagnose this way...


Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 15, 2020, 08:23:35 pm
Well, I have everything disconnected from the brick and it's in bypass mode. I replaced the two blown fuses with new 7 amp slow blow fuses and plugged in the unit. The fuses did not blow. So happy for that. So I totally disconnected the interlock switch and also the bottom on/off switch. I checked both switches with an ohm meter and they appear to be both working correctly. Continuity when on and no continuity when off. I also checked the switches for cross continuity across the polls. No chance of shorting there as well. So how can this unit be shorting out when the wires are connected to the switches? What are we missing?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 15, 2020, 08:43:31 pm
If you connect JUST the  interlock connector to J2 and power it up, does it blow a fuse?
then if you push/pull either of the interlock  switches  - does it blow?
If so - that is where the issue is...

The interlock switches are DPDT - I would think its *possible* for one of them to cross short in one of the three positions (momentary on/off/pull on)

You have 9 permutations with them

Switch 1     Switch 2
push on      push on
push on      off
push on      pull on

off             push on
off             off
off             pull on

pull on       push on
pull on       off
pull on       pull on

The interlock switches turn off/on the hot and the neutral at the same time..
Like I said - hard to *see* how you are checking..
But it still sounds like one of those two switches is bad based on the fuse not blowing with them disconnected.
That said -
You could keep the interlock on bypass, plug in the ATRII and see if you get all your voltages, then plug in the PCB.
You will be fine with the 6A fuse





Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 16, 2020, 07:32:00 am
ok - clearly I like a good puzzle..  My description above is for 2 interlock switches (for the upright)
But I think you only have a single interlock switch (I keep looking at my schematic)
This is yours - correct?

(https://i0.wp.com/bperkins.files.wordpress.com/2020/02/cocktail-interlock.jpg?ssl=1)

With both switches on - you should have continuity on the black wire only (pin 1 & pin 4)
and the white wire only (Pin 2 and pin 5)

You should never have continuity white to black, or white to ground (Pin 6) or black to ground
Hopefully that makes sense.

You are saying you are blowing 2 fuses every time?  F1 is the 7A - what fuse is the second 7A fuse?


Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 16, 2020, 07:35:21 am
Bperkins.
Look at the pic in reply 131.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 16, 2020, 07:44:39 am
OOOhhhhhhh  - is it F2 and F3 that are blowing.
ughh - my mistake  - can I delete my last 2 posts?    :embarassed:

I don't have the rest of that to look at..  That power brick is different than the upright..
I was looking at the 7A fuse in the primary side.




Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 16, 2020, 07:52:42 am
I will email you a good quality pic.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 16, 2020, 08:13:12 am
Looks like its the 10.3v circuit.

When you connect just the power brick (including the switches) nothing blows..  correct?

My guess is when you connect the ARII - that's when they blow.  (don't connect the PCB)
The 10.3v circuit has a bunch of chips in it that could cause a short.
Right in the middle of all of them is the LM305 voltage regulator chip you ordered with the power transistor.
Its a known troublemaker...  Did you replace it? if not.....

(again - so hard to do over a forum....)

Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 16, 2020, 09:20:33 am
Good morning all. I've been up since 5:00 this morning trying to figure this crazy problem out. I really never thought that the switches where causing the problem. So just to confirm that, I removed both of them from the equation and put a jumper across the two black wires and across the two white wires for the interlock switch. And Also did the same for the on/off switch at the bottom of the chassis. I also plugged in J2 to the chassis. Nothing else is plugged in. The PCB is disconnected as well as the ARII and as well as the monitor. And yes to the question are they both 7 amp fuses. F2 and F3 are both 7 amp fuses. As soon as I plugged the cord into the wall socket, both of the 7 amp fuses at F2 and F3 blow. To answer your question, "When you connect just the power brick (including the switches) nothing blows..  correct?" Now that I have those switches hard wired, the fuses will blow If I plug in J2. If I unplug J2 and put jumpers across the J2 socket on the brick, nothing blows. Which makes sense, there's no voltage being distributed to the harness and through the switches. Oh, and Yes, I did replace both of those parts yesterday. I thought I mentioned that above. Sorry. I guess we're back to square one. Where is this short coming from? Back to the schematic.:dizzy:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 16, 2020, 09:58:38 am
Good morning all. I've been up since 5:00 this morning trying to figure this crazy problem out. I really never thought that the switches where causing the problem. So just to confirm that, I removed both of them from the equation and put a jumper across the two black wires and across the two white wires for the interlock switch. And Also did the same for the on/off switch at the bottom of the chassis. I also plugged in J2 to the chassis. Nothing else is plugged in. The PCB is disconnected as well as the ARII and as well as the monitor. And yes to the question are they both 7 amp fuses. F2 and F3 are both 7 amp fuses. As soon as I plugged the cord into the wall socket, both of the 7 amp fuses at F2 and F3 blow. To answer your question, "When you connect just the power brick (including the switches) nothing blows..  correct?" Now that I have those switches hard wired, the fuses will blow If I plug in J2. If I unplug J2 and put jumpers across the J2 socket on the brick, nothing blows. Which makes sense, there's no voltage being distributed to the harness and through the switches. Oh, and Yes, I did replace both of those parts yesterday. I thought I mentioned that above. Sorry. I guess we're back to square one. Where is this short coming from? Back to the schematic.:dizzy:

Let me see if I can repeat this back:  (Just to be sure)
1. You bypassed the interlock switch and the on/off switch with jumpers on the actual wiring harness (testing for bad switches), left it plugged into J2 on the power brick and the fuses blow.  (yes/no?)
2. You unplug J2 from P2 on the power brick, Jump pins 1 & 4 (black) and 2 & 5 (white) on P2 (on the power brick) and the fuses do not blow?

But after that -
The only thing there is the bridge rectifier and the big blue cap - recheck the wires on them?  Maybe one got to the wrong place?
Maybe you got a bad rectifier?  With power and nothing connected to J5 - that's all there is connected to those 2 fuses.












Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 16, 2020, 10:33:57 am
Quote
1. You bypassed the interlock switch and the on/off switch with jumpers on the actual wiring harness (testing for bad switches), left it plugged into J2 on the power brick and the fuses blow.  (yes/no?)
Ans: Yes. But I physically removed the switches. Then the dangling wires that were connected to the switches is where I placed the jumpers across. And with J2 plugged into the brick, the fuse blows.

Quote
2. You unplug J2 from P2 on the power brick, Jump pins 1 & 4 (black) and 2 & 5 (white) on P2 (on the power brick) and the fuses do not blow?
Correct.

After looking at the schematic, That J2 being plugged into the brick only allows the unit to be switched on and off via the power switches. that's all. It doesn't supply voltage to anything. As a long shot, I'm going to again check the continuity on the white and black wires from the P2 connector on the brick to the white and black wires at the switches.

Like I said before, maybe I shouldn't have put in that bridge rectifier. The schematic that Mike sent me were different from the original schematic that I was working from. My schematic shows a bridge rectifier. Mike's schematic shows two diods instead of 4. Could that be the problem??? :dunno
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 16, 2020, 10:41:08 am
Quote
1. You bypassed the interlock switch and the on/off switch with jumpers on the actual wiring harness (testing for bad switches), left it plugged into J2 on the power brick and the fuses blow.  (yes/no?)
Ans: Yes. But I physically removed the switches. Then the dangling wires that were connected to the switches is where I placed the jumpers across. And with J2 plugged into the brick, the fuse blows.

Quote
2. You unplug J2 from P2 on the power brick, Jump pins 1 & 4 (black) and 2 & 5 (white) on P2 (on the power brick) and the fuses do not blow?
Correct.

After looking at the schematic, That J2 being plugged into the brick only allows the unit to be switched on and off via the power switches. that's all. It doesn't supply voltage to anything. As a long shot, I'm going to again check the continuity on the white and black wires from the P2 connector on the brick to the white and black wires at the switches.

Like I said before, maybe I shouldn't have put in that bridge rectifier. The schematic that Mike sent me were different from the original schematic that I was working from. My schematic shows a bridge rectifier. Mike's schematic shows two diods instead of 4. Could that be the problem??? :dunno

#1 - The short is here..  Its not the switches - its the wiring  - somewhere you have a black/white wire touching  or black to ground or white to ground..
The on/off switch and interlock switch to the EXACT same thing as #2 above.  it just allows the power brick to come on..

It still strange they are taking out the fuses on the secondary side - unless one of those wires is actually shorted to the secondary side (or mis-wired to it more likely)  either of those wires on the harness, shorting to the secondary side would to that..
I think you are on the 1 yard line...
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 16, 2020, 10:43:15 am
Check out reply 32 for a pic of the underside of the brick. That will show the Bridge rectifier and the big blue cap.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 16, 2020, 12:26:17 pm
Quote
somewhere you have a black/white wire touching  or black to ground or white to ground..

I believe from above statement, white to ground is fine. In the main panel box the whites and bare ground wires are all on the same bus. But black to white would be a short as well as Black to ground. Please tell me if there is something unique in this box that I'm not aware of. I'm pretty sure I checked and got continuity between white and ground. I'll check again.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 16, 2020, 12:31:24 pm
I will pull my monitor this afternoon so we can compare wiring jobs. I will take a bunch of pics.

Sent from my Pixel 3 using Tapatalk

Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 16, 2020, 12:46:37 pm
White to green, good, anything to black, bad...From what your saying I think, (and from looking at your volt chart) is everything is good until you hook up the interlock then the problem begins (but checked out as good)...Well That would suggest it is either wired incorrectly or something downstream is tripping those fuses...keep the board out of the loop until the end and voltages can be verified...So go back to the your "brick" it's not popping fuses, and aparently checks out fine with no load... This is your jumping off point, whatever you plug into it causes the trouble.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on February 16, 2020, 01:55:42 pm
Check out reply 32 for a pic of the underside of the brick. That will show the Bridge rectifier and the big blue cap.
Based on the schematic Mike posted, the cocktail should have a 2 diode full-wave rectifier, not the 4 diode bridge rectifier shown in the upright schematic.

The two types of rectifiers perform similar functions, but are wired to the transformer and C1 differently.

The full-wave rectifier applies a positive to the positive terminal of C1 from whichever diode is forward biased with the negative terminal of C1 tied to the center tap.
- Only one half of the winding is used at a time.
- Orange (ends) to violet (center) = 1/2 of orange to orange
- Think "top pushed up and bottom stays in the middle".

A bridge rectifier applies a positive to to the positive terminal of C1 from whichever diode on the top half is forward biased and applies a negative to the negative terminal of C1 from whichever diode on the bottom half is forward biased.
- Both halves of the winding are used at the same time.
- Think "top pushed up and bottom pushed down".

Correct me if I'm wrong, but it seems like the orange to orange windings for the transformers in the cocktail and upright would be different values for the different types of rectifiers to output the same voltage.   :dunno


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 16, 2020, 02:12:23 pm
I think you may have something there,Effectively a half wave rectification, that would explain why it is ok, until it has a load...Clever PL1😉
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on February 16, 2020, 03:29:32 pm
Thanks, Jennifer.   :cheers:

I agree about the "ok, until it has a load" part of your comment, but disagree about the "Effectively a half wave rectification" part.

A one diode half-wave rectifier would only use the positive part of the waveform -- but that's not the problem here.

(https://qph.fs.quoracdn.net/main-qimg-c77261755c6aa978f444108206fc7a66)

In this case, I'm referring to the transformer difference between the two types of rectifiers used to generate the same voltage (Vm) at the load. (RL)

Full-wave rectifier
- End tap to end tap (A to B) = 2 * Vm
- Voltage at load = Vm.
(https://www.elprocus.com/wp-content/uploads/2017/02/piv-of-center-tap.png)

Bridge rectifier
- End tap to end tap (A to B) = Vm
- Voltage at load = Vm.
(https://www.elprocus.com/wp-content/uploads/2017/02/piv-of-BRIDGE.png)

If you connect points A and B of the bridge rectifier circuit to points A and B of the full-wave circuit's transformer, you get twice the voltage (2 * Vm) applied to the load.

More details at https://www.elprocus.com/full-wave-bridge-rectifier-versus-center-tapped-full-wave-rectifier/ (https://www.elprocus.com/full-wave-bridge-rectifier-versus-center-tapped-full-wave-rectifier/).


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 17, 2020, 06:59:08 am
I have my cab all opened up. If you need pics of anything just let me know. I can leave the cab disassembled until the end of the month.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 17, 2020, 07:05:55 am
I ended up upgrading wifi yesterday.  The rectifier item is a good catch. 
If the on/off switch + interlock = sends power to pop the fuses - that certainly makes sense.
It doesn't make sense that if you bypass them with jumpers at the power brick - nothing happens.
But again - really hard to do this this remote.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:40:39 am
Good morning all. Scott, thanks for all the technical details of the two types of rectifiers. I had no idea that
there would be a voltage difference. So, if I'm understanding this correctly, by using the bridge rectifier instead
of the full wave rectifier configuration, the circuit is drawing twice the current. Thus, blowing the fuses across
the secondary winding of the transformer. This sounds like why both F2 and F3 fuses are blowing when power is turned
on. I'm glad I saved the full rectifier board. I pulled the brick out of the unit again and I'll reinstall the full
wave rectifier circuit board tonight. Do you think I'll need to replace the two diodes on the board? I already
restored the main fuse holder back to the original component. I agree Jen, it looked funky and I wouldn't have been
able to easily replace that fuse if it ever blew. I included more pics below to show the bypassed switches, the new
fuse holder and the full rectifier circuit board.

bperkins01, your absolutely correct, it doesn't make any sense to me either. By bypassing the switches at both switch
locations or by putting jumpers across J2 at the brick is accomplishing the exact same thing. That one is still stumping
me!  :banghead: I ordered two 7 amp circuit breakers. As soon as those come in, I'm going to hook them up and go over
that scenario again. This is driving me crazy.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:42:08 am
The pic below is the interlock switch bypassed.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:42:59 am
This pic is the main power switch bypassed.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:44:25 am
This pic is the Full Bridge rectifier board that I will be reinstalling.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:45:15 am
This pic is the bottom view of the Full wave rectifier board.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:46:48 am
Only had time to restore the main fuse holder back to using original component.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 17, 2020, 07:50:21 am
This pic is the solder joint of the bottle cap transistor. First time changing a Transistor component or a rectifier component for that matter.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 17, 2020, 08:29:49 am
Those traces look scary nasty and old to you I would imagine, (I dont know what they got for modern day replacements off hand) But they all do that, it is a age/heat thing and they are still good, Just get in and out (around 700deg.) While soldering them, excessive heat will make the problem worse, and solder pads will fall off...Then you are into patch wires, *not fun, or pretty.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 17, 2020, 08:56:27 am
On the ARII boards - they all kinda look like that..  Mine does..  agreed..  But it works  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on February 17, 2020, 11:18:52 am
So, if I'm understanding this correctly, by using the bridge rectifier instead of the full wave rectifier configuration, the circuit is drawing twice the current. Thus, blowing the fuses across the secondary winding of the transformer. This sounds like why both F2 and F3 fuses are blowing when power is turned on.
F2 and F3 blowing showed that you wired the bridge across that entire secondary winding (orange to orange) instead of one end to the center tap (orange to violet) which would only blow the fuse on that one orange line.

I haven't found a clear explaination what would happen to the current draw if you use a bridge rectifier in place of a full wave.   :dunno

Of course, that doesn't matter because you have the original board and it is easy to replace bad diodes.   ;D

Do you think I'll need to replace the two diodes on the board?
You'll need to test them.

https://www.youtube.com/watch?v=mMXDa5hVzXA


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 18, 2020, 06:28:01 am
Good morning all, Scott, thanks for that video above. Since I have to take the diodes out of the circuit to test, I thought I would just replace them. I also found another video on how to test a diode without a meter. They showed just using a 9 volt battery an LED and a 220 ohm resister. Either way seemed to be simple enough. I'm going to order those parts this morning. Maybe while I'm waiting for parts to come in I'll remove the monitor and take a closer look at the burned out chip. I know I'm going to have to order that part as well eventually. Thanks again for all that research. Have a good day.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 18, 2020, 09:01:23 am
And a cap kit...And a flyback, because that it most likely what welded that regulator like that with leaky high voltage, be carefull working on that thing.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: PL1 on February 18, 2020, 11:55:33 am
Since I have to take the diodes out of the circuit to test, I thought I would just replace them.
You don't need to desolder/remove the diodes from this board to test them.
- Black lead on the left and red lead on the right = forward biased.

(http://forum.arcadecontrols.com/index.php?action=dlattach;topic=161846.0;attach=381372;image)

Even if the board was fully installed, removing the "+" connection (lower left hole) or removing F2 and F3 would ensure there is no complete parallel path through other components that could cause misleading multimeter readings.

For circuits where there is no easy disconnect to isolate the diode (i.e. relay with snubber diode at 0:55), you can test it in-circuit using the resistance scale on your meter.

https://www.youtube.com/watch?v=FtiEEGBch4M


Scott
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 06:41:19 am
Good morning all. I took the time last night to test out the rectifier diodes on the board before replacing them. Please see the pics below to verify that these diodes may be ok. I used the diode setting on my volt ohm meter. With the positive probe of my meter on the cathode of the diode it always read 1, which on my meter is open (no continuity). With the negative probe of the meter on the cathode the reading keep changing. It read anywhere from 002 to 008. Just wondering if that is an acceptable range. I also switched the setting over to ohms, just to see what those readings would be. With the positive probe on the cathode the reading was the same as above for both diodes (no continuity). With the negative probe on the cathode for both diodes the reading was anywhere from .02 to 7.0. That reading keep changing as well. Do you think those readings may be acceptable? :dunno
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 06:43:24 am
The pic below is showing the reading of the first diode with the Negative probe on the cathode.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 06:44:55 am
This pic is showing the positive probe on the cathode of the first diode.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 06:46:28 am
This pic below is showing the positive probe of the meter on the cathode of the second diode.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 06:50:23 am
The pic below is showing the negative probe of the meter on the cathode of the second diode.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 07:40:39 am
From what I've read, I should be getting a forward bias reading of .2 to .7. Typically a .2 reading for the germanium type diodes and .7 reading for the silicon type diodes. It appears that I'm getting a short  reading on the forward bias for both diodes. What I didn't expect to see was a OL (Over limit), (1 on my meter), on the reverse bias for both diodes. From what I gather, both of these diodes are shorted! Back to the store!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 19, 2020, 07:49:25 am
Your meter is a bit confusing (to me)  - are the 007 and 008 really .007 and .008?
Certainly testing against a good one will tell you for sure.

You have diodes all over that machine to do some checking against.
Hope that's it!
Keep up the good work.

added:
Something killed them - be nice to know what.  (Maybe the old big blue?)
Buy a few extra diodes..  Just in case they pop.
I'd check the resistance across the secondary winding (both orange lines on F2 and F3) with the fuses pulled. 
It should NOT show shorted..  not sure how many ohms you should have... but not shorted.

While I was at it - I'd check for continuity from those same spots against all of the connections on the primary side of the transformer.. just in case.  they should all show open based on the schematic.  right?
Transformer failure is very uncommon..  but not unheard of...


Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 11:36:12 am
I'm not crazy about my ohm meter either. Sometimes It doesn't appear to be that accurate. I thought those shorts would have shown a .002 reading, instead of a 002 reading. But I'm pretty much convinced that those diodes are showing a short condition and should be replaced.

Would you or Mike or Scott be able to upload a current full schematic of the power supply? The cocktail table schematic should show the two diode rectifier instead of the half wave rectifier. I feel any further testing of the brick will be more accurate with the correct schematic. Thanks.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 19, 2020, 11:41:57 am
Pay no attention to the red arrows - I saw this on another thread - but this is the one you have..

(http://i.imgur.com/wn7jze5.png)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 19, 2020, 11:42:37 am
I just emailed you a copy too.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 19, 2020, 02:55:22 pm
Thanks, both of you!! :cheers:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 21, 2020, 07:18:44 am
Good morning all, TGIF! Now that my 7 amp circuit breakers came in, I'll be looking for that short circuit over the weekend. I'm hoping that those rectifier diodes (MR750) come in today or tomorrow as well. I finally found someone who had them. I ordered them from Digikey who actually located them at Rochester Electronics. Rochester Electronics only had one pack of 25 for 5 dollars left. The killer was the $10 dollar S&H charge I had to pay. As was mentioned in an earlier thread, something must have caused those MR750's to short out. Maybe it's a good thing that I'll have a few extra, just in case. I'd like to put this brick back together and come to a determination if any of the windings on the primary or secondary side of the transformer are actually shorted and causing all my problems. Enjoy the weekend.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 21, 2020, 07:22:13 am
Winding shorts you can test while you wait.  *if* its there - it will be between that winding and one of the others.  Good luck.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: pbj on February 21, 2020, 09:39:22 am
Throw that piece of ---steaming pile of meadow muffin--- multimeter away and get something that actually works. 

 :cheers:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 24, 2020, 10:35:49 am
Good morning all. I'd like to give an update as to where we are currently with this restoration. Originally and currently the game has no life other than the red lights at the two coin slots. We have many good voltages but seem to be missing some 5 volt readings. So to correct that issue, as was suggested, I replaced the 2N3055 (Q3) Transistor and also the LM305 5-volt Linear Voltage Regulator (Q1) on the ARII. Iím anxious to re-test those voltages and continue to move forward.

Problem 2 Ė As mentioned early on, before joining the forum, I replaced the Big Blue Cap as well as the rectifier circuit. Not having the correct schematic, I replace the full wave rectifier with a half wave rectifier. Now that I have the correct schematic for this cocktail centipede game, I removed the have wave rectifier and ordered two MR750 diodes to replace the shorted out diodes on the original full wave rectifier circuit board.

Problem 3 - Additional Short Circuit problem Ė F2 and F3 (7 Amp) fuses blow every time I plugged in the J2 connector to the Power Supply. This could have been the result of having the wrong type rectifier in circuit. Those MR750 diodes should come in today. Tonight, Iím hoping to re-solder those diodes and install the original full wave rectifier circuit board. Iíll give another update tomorrow.

Last night, since the 7-amp circuit breakers arrived, I connected those to the F2 and F3 fuse connector block. With the J2 jumpers in place (bypassing the interlock switch and the bottom switch) and the rectifier circuit still disassembled, I plugged the unit in. No fusses blew.  Since the rectifier circuit was disassembled, I thought I would take a reading off that top secondary winding. So putting my leads across the two orange wires, I got a voltage reading of 19.3 VAC. I was always curious as to what that voltage off the secondary prior to the rectifier circuit would read. Hoping to see 10.5 DC after the upgrade. Hopefully Iíll be able to give a more informative update tomorrow.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 28, 2020, 08:57:42 am
02/28/2020

TGIF, Good morning all, Happy to report that the above Problem 2 and Problem 3 have been resolved. The MR750 diodes have been re-soldered to the original full wave rectifier board. See pic below. I retested all the J5 secondary winding output voltages with a load again and all is still good.

Additionally, I hooked the brick back up in the cabinet and removed the J2 jumpers that were in place to bypass the interlock switch and the bottom switch. I plugged in the J2 connection instead and turned the game on. No fuses blew. Now I feel weíre making progress.  I currently have the bottom switch hooked up, but I have the top interlock switch still removed from the circuit.

Moving forward Ė Tonight, Iíll reconnect that top interlock switch in place and start re-connecting the additional boards. Iíll start with the PCB board. If no fuses blow, Iíll continue to connect the ARII. At that point Iím hoping to see the red power light on the PCB. With the new Transistor and voltage regulator now replaced, Iím anxious to retest the ARII for those missing 5 volt readings. If all goes well, I report back tomorrow with additional more promising news. Have a good weekend!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 28, 2020, 08:59:42 am
The pic below showing the brick with the rectifier restored back to original configuration.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 28, 2020, 09:00:33 am
Kudos to you for sticking with it.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 28, 2020, 03:21:18 pm
02/28/2020

TGIF, Good morning all, Happy to report that the above Problem 2 and Problem 3 have been resolved. The MR750 diodes have been re-soldered to the original full wave rectifier board. See pic below. I retested all the J5 secondary winding output voltages with a load again and all is still good.

Additionally, I hooked the brick back up in the cabinet and removed the J2 jumpers that were in place to bypass the interlock switch and the bottom switch. I plugged in the J2 connection instead and turned the game on. No fuses blew. Now I feel weíre making progress.  I currently have the bottom switch hooked up, but I have the top interlock switch still removed from the circuit.

Moving forward Ė Tonight, Iíll reconnect that top interlock switch in place and start re-connecting the additional boards. Iíll start with the PCB board. If no fuses blow, Iíll continue to connect the ARII. At that point Iím hoping to see the red power light on the PCB. With the new Transistor and voltage regulator now replaced, Iím anxious to retest the ARII for those missing 5 volt readings. If all goes well, I report back tomorrow with additional more promising news. Have a good weekend!

I'd consider hooking up the PCB last - you want all the power right before blowing that up....  I went Power Brick --> ARII -->  PCB

Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on February 28, 2020, 09:53:33 pm
02/28/2020

TGIF, Good morning all, Happy to report that the above Problem 2 and Problem 3 have been resolved. The MR750 diodes have been re-soldered to the original full wave rectifier board. See pic below. I retested all the J5 secondary winding output voltages with a load again and all is still good.

Additionally, I hooked the brick back up in the cabinet and removed the J2 jumpers that were in place to bypass the interlock switch and the bottom switch. I plugged in the J2 connection instead and turned the game on. No fuses blew. Now I feel weíre making progress.  I currently have the bottom switch hooked up, but I have the top interlock switch still removed from the circuit.

Moving forward Ė Tonight, Iíll reconnect that top interlock switch in place and start re-connecting the additional boards. Iíll start with the PCB board. If no fuses blow, Iíll continue to connect the ARII. At that point Iím hoping to see the red power light on the PCB. With the new Transistor and voltage regulator now replaced, Iím anxious to retest the ARII for those missing 5 volt readings. If all goes well, I report back tomorrow with additional more promising news. Have a good weekend!

I'd consider hooking up the PCB last - you want all the power right before blowing that up....  I went Power Brick --> ARII -->  PCB
I know right?...Must have told him a hundred times, But At this point, it's pretty obvious the problem.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on February 29, 2020, 04:20:32 pm
IT'S ALIVE! IT'S ALIVE! The game is finally showing some signs of life now. I think I still have a ways to go yet. Like I said Friday, I reconnected the interlock switch, and turned the machine on. So far so good, no fuses blown. I reconnected the plugs to the PCB board and turned the machine back on again. Still looking good. I reconnected the ARII, turned the game back on and all the lights came on. The PCB board LED light, the two coin receptor lights, plus the two LED's above the coin receptor. The speaker was even making some noise. For now, I left the monitor unplugged. I noticed that the two LED lights above the coin receptor were blinking, so I inserted two coins. I pushed those LED buttons and it sounded like the game was playing. I was pressing the fire button and rolling the yellow ball. The sound coming out of the speakers was a little fuzzy and staticy, but it sounded like it was working. So now I thought I'd plug in the monitor just to see If it would light up. Nothing. So I disconnected the monitor and checked the voltages on the two plugs. Still no voltage on the six pin plug, and 126 volts on the three pin plug just like before. I left the monitor unplugged and turned the game back on again, but can't get it to sound like it's playing. I hope I didn't cause any damage by plugging in the monitor. Any clue why the 6 pin monitor plug has no voltage? Do you have a schematic of that plug showing pin voltages? I have a feeling that the next step is going to be to remove the monitor from the chassis. As you mentioned previously, that one fried part on the monitor circuit board might be a voltage regulator. Well, one step at a time. What are your thoughts?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: Mike A on February 29, 2020, 05:22:56 pm
The six pin plug is the video signal from the PCB. RGB sync, and ground. Check the fuses on your monitor.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on February 29, 2020, 07:00:32 pm
Testing the 6 pin plug is a lot like testing an HDMI cable..  you would be testing red/green/blue/video signal..  and they would be jumping around..    I'd be surprised if your meter could lock on an voltages in the first place.

Your real issue is how to test the monitor..
It's going to be best to test it on the bench..
There are troubleshooting guides for it too.. 

Check to make sure you didn't blow any fuses again..
To get sound with centipede - you need to coin up - then the player 1 button will light..  then start .. should get sound.
At that point - you should focus on the monitor.

Obviously that fried chip needs help..
There is also a voltage test called B+ 
Its the first thing to check

Glad to see you made progress!


Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 01, 2020, 01:57:49 am
Thanks guys for all the encouragement and great advice! :cheers:  Now it's monitor to bench time. I'll let you know the status of the fuse and other parts once I take a good look at everything. First with the obvious fried chip and I'll see what I can find out on that voltage B+ test. Thanks again! Have a great day.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:48:42 am
Good morning all, Well, on to phase two. I removed the monitor from the chassis and itís now on my work bench. The fuse tested out to be good. That bad component that we looked at awhile back, no longer looks like a chip to me. I thought it was going to be a 10 or 12 pin chip that I could easily remove and replace if need be. The component looks like itís made up of a couple coils soldered directly to the circuit board. I took another picture of it from a different angle. See below.

Additionally, I watched a couple videos of testing the B+ voltage. One video was saying that the voltage they weíre looking for was 208 VDC, while another video was looking for a 108 VDC. Does anyone know the exact voltage for my Hitachi monitor? This monitor is type 37OESB22, Model: 13Ē COL GAM MNT. I couldnít find any video specifically for the Hitachi. Also, when Iím test for this B+ voltage, can I just make a patch cable to supply the initial 120 VAC to the 3 prong plug? Iím going to try to get started tonight with this additional testing.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:50:00 am
IT'S ALIVE!!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:51:30 am
Bad Component. Different angle.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:52:20 am
Bad component.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:53:39 am
Monitor info.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:54:33 am
More Monitor info
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 11:55:27 am
Additional Monitor Info below
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 02, 2020, 11:55:46 am
Make sure you use the power from your Atari Power brick!  DO NOT CONNECT IT TO A WALL OUTLET!

It needs to be on an isolation transformer (or you risk frying lots of things)

There should be other information on your monitor..  Are you getting that number from the tube?
Title: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 02, 2020, 11:57:35 am
Hitachi is just your tube. Your monitor is an Electrohome. Look for info/schematics for the chassis.

Itís a GO7-FBO.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 02, 2020, 11:58:46 am
.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 02, 2020, 01:32:45 pm
Thanks guys. Good to know!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 02, 2020, 01:53:57 pm
Start here:


https://www.arcade-museum.com/manuals-monitors/Electrohome%20G07%2013in%20and%2019in%20Color%20Raster.pdf
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 04, 2020, 06:16:50 am
Good morning all, after removing the monitor from the chassis and taking a good look around I did notice another smaller fuse. See Pic below circled in red. I believe itís the F901, 1 AMP 250V. I tested it and that fuse is blown. It doesnít look like itís in a socket. Is that fuse soldered in place? It actually looks like both fuses are soldered in place. I canít image having to de-solder and re- solder a fuse when it blows. Has anyone ever had to replace that mini fuse? If that is a specialty type fuse, does anyone know where I can purchase it? With the Monitor schematic now in-hand, (Thanks again to yotsuya  :cheers:), I believe what previously looked like a bad chip is really a side pin Transformer (T1503). See additional pic below. Also looking at the schematic for my 13Ē (SU1103A) monitor, and please correct me if Iím wrong, but it looks like the B+ is tested from the B1 pin and adjusted at R909. weíd be looking for 120V DC reading. I really want to order and replace that fuse first. I may not see a voltage without it. Any comments? Have a good day.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 04, 2020, 06:18:22 am
See pic below, circled in red, showing blown mini fuse.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 04, 2020, 06:20:31 am
See pic below showing a better angle of the, what I believe to be, the Side Pin Transformer (T1503).
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 04, 2020, 07:07:27 am
Iíve changed that fuse many times, believe me.

You can find them here, buy a few of them:

https://www.arcadepartsandrepair.com/?s=G07+fuse&post_type=product

Quite a few collectors will add an inline fuse holder here, running wires to this spot and mounting it off to the side.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 04, 2020, 08:48:21 am
Quite a few collectors will add an inline fuse holder here, running wires to this spot and mounting it off to the side.

I would to this ^^^

Add a fuse holder so the fuse is not soldered to the board.
You can get a 1A / 250v at a hardware store.. its very common.  There is nothing special about it.  Its a standard fast blow fuse.
Since you don't (really) know what blew it...  A fuse holder and a few spares makes sense.
Then once you get it all sorted out - if you want to make it *original* again..  Do the solder on the board fuse..

That little transformer is likely fine..  They don't normally die..

I looked in the manual  (B1 = B+) in your case.. 

Keep in mind its 120v DC  The very first time I saw the 120 and just set my meter to AC.. (wrong..)

That fuse is really early in the circuit too.. Maybe it blew as a result of the power supply?  Not sure.. 
Keep at it!

Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 04, 2020, 08:51:31 am
I had one where the flyback was the cause of it blowing.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 04, 2020, 08:52:45 am
Oh, and read this before you do anything:


https://forums.arcade-museum.com/showthread.php?t=138118
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 04, 2020, 08:55:53 am
And this helps too

(https://uploads.tapatalk-cdn.com/20200304/41657fbe418a8cc3cd430e68436ed721.jpg)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 09, 2020, 06:55:50 am
Good morning all, Well, this weekend was quite productive. I removed the bad 1-amp fuse and soldered in an inline fuse holder. To make the job easier, I constructed a simple wooden frame to attach the circuit board to. See pic below. With this setup I was able to easily get to the front and back of the circuit board without having to detach too many wires.  I also made a 1-foot lead wire and attached it to the B1 pin. Tonight, when I re-install the monitor back into the chassis, Iíll be able to test and adjust the 120 VDC B+ voltage. Hopefully, Iíll have more good news tomorrow morning. Now Iím hoping to see this monitor light up.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 10, 2020, 06:31:49 am
Bad news this Tuesday morning. After hooking the monitor back up into the chassis, and turning the power on, that mini fuse blew again, and still no power to the monitor. The B+ didnít even show a reading at all. 0 VDC. It looks completely dead. It would be nice to have a flow chart like yotasuya posted, but start from power to the monitor/no power to the monitor. See pic below. (Just an example) I think this might be where I have to purchase and replace all the caps and flyback. There must be a more logical approach. Right? Also, aside from the monitor, I thought Iíd try to see if the game would fire up again. I put two quarters in and pressed the two LED buttons. Nothing. It only happened that one time, where it sounded like the game was active. Sound was coming from the speakers and pressing the buttons was producing game sound like activity. I felt I was reaching a progress plateau. Donít know what to think now. Any suggestions? Thanks.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 10, 2020, 08:14:50 am
Its the very first step in the chart.. test the horizontal output transistor.  It is the most likely part to have failed (X01)
Did you check it?

I would check/replace that before doing all that other stuff.  Its the hardest working part on the board.. 

The flow chart is for troubleshooting symptoms - the flow chart you are asking for is the schematic.. You have that.  Its just knowing how to read it (not always the simplest thing)
If the game is not active - you may need to wait until you can see whats actually happening..
If the red LED is on  - they you may have a board problem.  But hard to tell w/o a screen to help you.

Check that transistor first before spending money on a flyback.. A capkit isn't (likey) going to stop fuses from blowing ..  it will help fix distortion and wavy screens.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 10, 2020, 10:20:08 am
That flyback has shot voltage and welded parts around it, To not order one is an experiment in futility, the H/output should be replaced regardless, however, that chassis has seen high voltage, where it dont belong, so theory would dictate H/out got damaged also, And only a fool wouldn't put new caps on it...Be cautious working on it, that thing could bite you hard without warning.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 10, 2020, 10:31:13 am
That flyback has shot voltage and welded parts around it, To not order one is an experiment in futility, the H/output should be replaced regardless, however, that chassis has seen high voltage, where it dont belong, so theory would dictate H/out got damaged also, And only a fool wouldn't put new caps on it...Be cautious working on it, that thing could bite you hard without warning.

Did I miss that picture?  I hadn't seen a fried flyback..  If the caps are original, I'd replace them..  but not before knowing what's blowing the fuse.  Horizontal output transistor check is step1.

http://www.pinrepair.com/g07/ (http://www.pinrepair.com/g07/)  - this looked good too as a reference
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 10, 2020, 12:06:07 pm
This pic is showing what appears to be a bad part.
That's bad flyback if I ever saw one, tried to tell him all the way back at the beginning of this thread...But it really dont matter much anymore I supose, also said "Dont hook up that board till the end,and your voltages check out" and now it is apparently not working anymore, probibally fried it from the description....But I got to say B/perk, that was a nice entry level write up on board repair you did, Just saying ::).
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 10, 2020, 12:44:09 pm
This pic is showing what appears to be a bad part.
That's bad flyback if I ever saw one, tried to tell him all the way back at the beginning of this thread...But it really dont matter much anymore I supose, also said "Dont hook up that board till the end,and your voltages check out" and now it is apparently not working anymore, probibally fried it from the description....But I got to say B/perk, that was a nice entry level write up on board repair you did, Just saying ::).

Thanks Jennifer - that pic you referred to is of a small transformer/coil  (which from the original angle looked like a chip... it was not of course)..  I didn't see a pic of the flyback in this thread.
The Horizontal output transistor should be easy to get to and test.. 
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 10, 2020, 02:09:23 pm
Well...That coil is spattered with molten steel most likely with high voltage, and look what is right next to it...You guessed it, The flyback...With liquefied coil leading right to it.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 10, 2020, 02:46:17 pm
Well...That coil is spattered with molten steel most likely with high voltage, and look what is right next to it...You guessed it, The flyback...With liquefied coil leading right to it.

Well there you have it - pictures of the flyback needed  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 10, 2020, 03:07:41 pm
The whole project should only cost around 60.00, and pretty much everything new, Flyback, H/trans, coil, and caps...Problem is that most likely is a 13" (cocktail) and he most likely won't find a flyback, However the 19" works with circuit mods...But I ain't the one to tell him that, cause I already tried pointing it out like 6 pages ago...That and the board is probibally in need of work now anyway...Good luck man.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 10, 2020, 03:11:00 pm
I did miss it... I went back and looked..  good catch.
I'd still like to see the crud leaking out too..
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 13, 2020, 06:13:29 am
TGIF! Going into this weekend and into next week, Iím on a mission to replace the caps, X01 and flyback transformer. The only wall Iím confronted with is the fact that it appears that no one carries a T502 (A19183-A). What do others do that have a 13Ē monitor and need a flyback? When reading the reviews on the 19Ē flybacks, used for a 13Ē monitor, repair techs are saying that the video output display will be larger and require modification of the circuitry. Thanks for that link by the way, showing how to test and replace all these parts.  All seems necessary but somewhat time consuming. Starting with the caps and H/Out, will definitely keep me busy for a while. Maybe I should see if I can find a good used flyback? Any suggestions? Have a good weekend all!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 16, 2020, 06:32:33 am
Good morning all. Above parts have now been ordered, except for the flyback. Iíll probably order that part when I return from vacation. Has anybody seen or come across any videos on the circuit modifications that are necessary when using a flyback for a 19Ē monitor? Iím curious as to the extent of this endeavor. With my vacation quickly approaching and the additional work required on this monitor circuitry, my forum communications will be limited. The next time I turn this game on, all the new parts will be in place and hopefully Iíll just need to make minor adjustments. Thanks again for everyoneís suggestions and support. :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 17, 2020, 09:34:36 am
Its going to be pretty difficult to help fix a CRT via a forum... 

Were you able to test the horizontal output transistor?
Do you have a visible crack and leaking from the flyback?  I've only seen the picture from above.. you can remove that now and check all around it..

Replacing everything can make things worse w/o knowing if these are the only two issues..



Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 17, 2020, 10:32:04 am
Good morning Perkins, Yes, I was able to test the horizontal output transistor and it is bad. I believe it had a reading of .002. I believe it's shorted out. As far as the flyback is concerned, there is no visible signs of damage. No visible cracks or leaking. Other than being dirty, it looks good. When you say that "I can remove that now", do you mean that I could de-solder the flyback from the board now? If you think it will help, I can take more pictures of the flyback from different angles. Those parts I ordered should be here any day now. For sure I need to replace the H/Out. What do you think?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 17, 2020, 10:46:54 am
My flyback is bolted on so its easy to remove and inspect the area I can't see.
If there are no VISIBLE cracks and leaks on your flyback, I'd put the horizontal output transistor in and try it that way.  Whats the worse thing that can happen?  You blow a $4 part?  You already know its bad and its the #1 part that fails..

If the flyback is soldered to the board and there is the potential for a crack/leak on the underside of it that isn't visible.. Remove it and be sure.  If its clean, I'd put it back and test it with the new transistor.  Their *normal* failure is overheat, crack, melt, eject goo...  If none of that is happening..  why replace it?

Install the transistor - 10 minutes work and see if progress is made.


Title: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 17, 2020, 11:07:39 am
If there are no VISIBLE cracks and leaks on your flyback, I'd put the horizontal output transistor in and try it that way.  Whats the worse thing that can happen?  You blow a $4 part?  You already know its bad and its the #1 part that fails..

Install the transistor - 10 minutes work and see if progress is made.

Thatís why I usually get multiples of any chip, IC, or transistors I order, if possible. You never know....
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 17, 2020, 11:13:08 am
If there are no VISIBLE cracks and leaks on your flyback, I'd put the horizontal output transistor in and try it that way.  Whats the worse thing that can happen?  You blow a $4 part?  You already know its bad and its the #1 part that fails..

Install the transistor - 10 minutes work and see if progress is made.

Thatís why I usually get multiples of any chip, IC, or transistors I order, if possible. You never know....

oh yea..  My spare parts are multiplying quickly..  *feels* less painful ordering a bunch of stuff at once and reducing the shipping overall cost.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 17, 2020, 11:15:49 am
If there are no VISIBLE cracks and leaks on your flyback, I'd put the horizontal output transistor in and try it that way.  Whats the worse thing that can happen?  You blow a $4 part?  You already know its bad and its the #1 part that fails..

Install the transistor - 10 minutes work and see if progress is made.

Thatís why I usually get multiples of any chip, IC, or transistors I order, if possible. You never know....

oh yea..  My spare parts are multiplying quickly..  *feels* less painful ordering a bunch of stuff at once and reducing the shipping overall cost.  :)
Yep -  nothing worse than blowing a specialty fuse or some other item and having to reorder, wait for it to come again, pay again for shipping, etc. - especially if they are cheap parts. Better to have a little stockpile to help save time, more than money!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 17, 2020, 11:21:39 am
Quote
Yep -  nothing worse than blowing a specialty fuse or some other item and having to reorder, wait for it to come again, pay again for shipping, etc. - especially if they are cheap parts. Better to have a little stockpile to help save time, more than money!

Agreed - my Mouser.com  74LSxxx chip collection is up to 27 SKU's just because I can't bare to buy the 1 stupid IC I want and pay $8 to ship it..
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 17, 2020, 11:46:50 am
Sounds like a plan. When the parts come in I'll replace the H/Out, thoroughly inspect the flyback and give it a try. I'll let you as soon as all that is completed.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:11:18 am
Perkin, Last night I disassembled the monitor circuit board from the monitor. Since Iím going to be replacing parts soon, I thought this would be a good time as any to get started. This also gave me a much better view of the flyback and other components. I cleaned up the flyback the best I could and took some pictures of the front and back side. I also noticed some discoloration in the center of the board. Not sure how serious this might be. I also noticed what looks like flyback splatter toward the inside back of the cabinet. Only thing is, Iím not sure if this is an old war injury from a previous problem or if this is the cause of my current problem. I can only speculate as to what might have happened. See all pics below.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:12:17 am
Pic below shows Flyback front view.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:13:17 am
Pic below shows flyback rear view
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:14:28 am
Top monitor board view.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:17:00 am
From the top monitor board view and this view below, I'm see a lot of heat discoloration.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 07:19:21 am
This pic below showing that flyback splatter from inside the back wall of the cabinet.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 18, 2020, 08:24:07 am
It looks like its been recapped and worked on previously.  No indication of anything on your flyback to me either.  I'd leave it for now.

The dark burned up area inside the heat sinks looks like parts have been replaced there too..(maybe the resistor burned up?  the one that's there looks new and the source of the burn marks.

Put the H/O transistor in and try it is my suggestion based on what I'm looking at...
If it works - I wouldn't replace anything else..
Hopefully you get the part today.


Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 18, 2020, 11:05:20 am
Sounds good. Sometimes it feels like we're involved with a crime scene investigation.  What component did it and why. too funny. I believe those parts will come in today or tomorrow.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 18, 2020, 11:25:45 am
Some of it is CSI work..  But those NTE Caps all look new, I think they have data codes on them... But I'm not sure..
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 20, 2020, 06:17:53 am
I had a chance to replace the H/Out last night. I'll also replace that mini fuse and put everything back together as you suggested. Hoping to see some life with this monitor so I can check the B+ and make some final adjustments. I'll try to get back online Saturday to give another update.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 22, 2020, 11:02:45 am
After, replacing the H/out resistor and mini 1 amp fuse, I put everything back together and placed the monitor back in the cabinet. I turned the power back on and still no difference. The mini 1 amp fuse blew again and still no power to the monitor. I thought for sure that would have worked. I ordered a Fluke 15B + F15B+ Digital ohmmeter today. That should be here in a day or two. I'd like to re-test out that H/out transistor again and maybe the voltage regulator (2SC1106) transistor? Something must be blowing that mini fuse. Just not sure what it could be. Any suggestions? :dunno
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 22, 2020, 03:03:09 pm
Fly back. I had the same issue on a G07. Once I replaced the fly, it was golden.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 22, 2020, 04:37:13 pm
yotsuya, I heard that there are no Flybacks available for a 13" monitor like I have. The only ones flybacks out there are for the 19" monitors. I heard that if I decide to order and install one of those, I'll need to make some circuit modifications. Do you know what circuit modifications they're talking about? Is this a major project? Is there any information or videos on this that I can look at? What are your thoughts?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 22, 2020, 05:54:03 pm
yotsuya, I heard that there are no Flybacks available for a 13" monitor like I have. The only ones flybacks out there are for the 19" monitors. I heard that if I decide to order and install one of those, I'll need to make some circuit modifications. Do you know what circuit modifications they're talking about? Is this a major project? Is there any information or videos on this that I can look at? What are your thoughts?
I wish I could help, but Iíve never changed a flyback on a 13Ē monitor. My experience would tell me that would solve your problem, but I donít know where to source one.

Let me ask around and see if I can find anything for you.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: yotsuya on March 22, 2020, 05:59:18 pm
This looks like a pretty good thread to look at:


https://forums.arcade-museum.com/showthread.php?t=413125
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 23, 2020, 06:58:04 am
yotsuya, Thank you so much!, a great link with great information! Now off to ordering more parts.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 23, 2020, 09:44:07 pm
Is unfortunate its putting up such a fight..
Was there a way to test the voltage regulator/transistor?  Looks like another low cost component..

Maybe you can check for shorts on the coils in the flyback? I've never checked one..
It would be better if you knew with certainty that was the issue..

Replacing everything w/o knowing who is causing the issue is likely to create new problems.. But you've been living it...

Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 24, 2020, 07:42:10 am
Quote
Was there a way to test the voltage regulator/transistor?  Looks like another low cost component..

Maybe you can check for shorts on the coils in the flyback? I've never checked one..
It would be better if you knew with certainty that was the issue..

I agree. My new meter should be here any day now. I want to recheck the H/Out and also check the X02 for a short. I have the extra parts. It wouldn't take much to change out that voltage regulator transistor as well. When I remove the Flyback I will definitely check it out the best I can. It would be nice if it could be repaired. I'll include some pics if there are any visible signs of damage. Worst case scenario, I replace the flyback with a A29951B and modify the horizontal width circuitry with the correct value combination of chicklets. I'll keep you posted.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 24, 2020, 06:40:35 pm
Looking good... :cheers:
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 30, 2020, 07:03:12 am
Good morning all, quite an eventful weekend. I had a chance to replace most of the caps from the cap kit that I ordered. I would have replaced them all, but 7 of them from the kit were incorrect. See Pic below.  A couple examples: My C303 cap had a value of 10uf @ 250V, the kit supplied a 22uf @ 50V replacement. My C504 had a value of 1uf @ 160V, the kit supplied a 1uf @ 50V replacement. The list sheet stated a higher voltage would be ok, but not a lower voltage. See pic below for full original values and supplied values. Iím going to try to contact Arcade Parts and Repair today to try to exchange the incorrect valued caps for the correct ones. The blue dot on the sheet below indicates the caps that I was able to correctly replace.  Iím just noticing that Iíll have to un-solder C408. The replacement cap voltage is too low. Iíll double check all the polarities before I move on.
Additionally, I was able to un-solder the Flyback. I flipped it over and took a picture of that as well.  See pic below. I would have taken a reading of the coils, but I donít know what the values should be.  I also want to check out Resistor R908. One of the links I read said to check the value and replace if necessary. I feel steady progress is being made. Still much to be done. Any thoughts?
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 30, 2020, 07:04:21 am
See Pic below shows underside view of the Flyback.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 30, 2020, 08:59:03 am
That flyback looks good to me.. 
Not cracked or melted.. w/o knowing the expected values - you should be able to test for shorted windings using the schematic..

Bad caps are not known to cause fuses to blow..  they create crappy pictures when they are bad.
There are a bunch of threads on that monitor about cap sizes, etc..  but all related to crappy pictures, colors.



Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 30, 2020, 02:59:02 pm
That flyback looks good to me.. 
Not cracked or melted.. w/o knowing the expected values - you should be able to test for shorted windings using the schematic..

Bad caps are not known to cause fuses to blow..  they create crappy pictures when they are bad.
There are a bunch of threads on that monitor about cap sizes, etc..  but all related to crappy pictures, colors.
I am actually a bit confused as to why you would be giving this guy false hope...Supose a 30.00 flyback is life changing money or something, But even if that one is not the problem by some miracle and it still works...Most likely within 6 months those new caps are going to blow it out anyway.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 30, 2020, 03:10:39 pm
That flyback looks good to me.. 
Not cracked or melted.. w/o knowing the expected values - you should be able to test for shorted windings using the schematic..

Bad caps are not known to cause fuses to blow..  they create crappy pictures when they are bad.
There are a bunch of threads on that monitor about cap sizes, etc..  but all related to crappy pictures, colors.
I am actually a bit confused as to why you would be giving this guy false hope...Supose a 30.00 flyback is life changing money or something, But even if that one is not the problem by some miracle and it still works...Most likely within 6 months those new caps are going to blow it out anyway.

Not my intention - he was having difficulty finding the correct one, requiring him to not use an exact replacement,  That required another layer of modifications to make the wrong one work.
My opinion is to find the cause of the issue and fix that first.  Not replace everything and hope I got it..  Replacing caps is a great idea.  Injecting more change into the equation (caps) before knowing why its blowing fuses in the first place complicates the matter IMHO. 

Tougher than that is trying to help repair a CRT over the internet.. A forum is to solicit opinions - he doesn't have to listen to me - but it helps to have a few to think about.  that's all.  I've politely not listened to many opinions over the years.   Still learned from them.

Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 30, 2020, 03:22:41 pm
Oh, Well in a strange way that does make sense...That chassis looks tired, and could be a good candidate for replacing, but in the interest of fixing it, I would personally change pretty much everything, But at the very least, caps and flyback (The hard part is already done since it is already out.)😉
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 30, 2020, 09:00:26 pm
Vapuser...You do have options, depending on your level of OCD.. That tube could also be issue, If that were on my bench That would have been my first test, and a clean and balance, if it is burnt, or faded you are going to end up with that when this is over, If the tube is shorted, (very rare) it will fry your fresh new chassis in the blink of an eye...13" TVs are quite common, and offer an alternative, either hack RGB to the receiver, or use output jacks...Or use an universial chassis (by counting pins on donor tube, and measuring deflection resistance...Either way there is no shame in either, makes for good color, and a fun game to play at the end of the day.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on March 31, 2020, 07:58:28 am
Good morning, Good news, bad news. The good news is that Arcade Parts and Repair has confirmed that all their replacement caps in their cap kits are an accurate representation of what needs to be replaced.  They stated that if there is a discrepancy in the cap values, chances are that they were previously, replaced with an incorrect value. That was good to hear. Now I can continue replacing the remainder of the caps. The bad news is that after checking the resistance across the windings of the flyback, they all showed a shorted condition. I first checked for a value between pins 1 and 3. The reading rapidly went from 1.0 to .9 then .8, .7, .6. Same across pins 4 and 5, 6 and 7, and also 6 and 10. When I changed the meter to indicate a tone for a short, all above readings toned out. Short, short, short, short. So maybe this can be construed as good news as this definitely confirms the reason for the 1-amp fuse to blow. I think now we can feel confident that the flyback definitely needs to be replaced. Iíll place that order today and give another update in a few days.
Jennifer, I can only wish that I had your level of expertise. I wouldnít even know where to start with what you suggested. Perkins and I were on the same page with trying to determine what is actually causing that 1-amp fuse to blow. I think now it is quite evident that the Flyback was the culprit. Which is something that you instinctively knew from the beginning. My thoughts are, that Iím going to replace the rest of the caps and the flyback, hope that I have video, check my B+, correct the horizontal issue with a correct value combination of chicklets and take it from there. If this game works after all that Iíll have you guys to thank for it. I already appreciate all of your help and suggestions!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on March 31, 2020, 08:25:50 am
That would be great news if it was internally shorted.  I personally like knowing the cause.  If I wanted something to work w/o knowing why..  I'd send it out to an expert. 
Since you are putting in the effort to repair this yourself - you seem to want to know *why* and have put in a lot of troubleshooting.
Confirming a failed component is the best..
Hope it is it!
keep up the good work.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: jennifer on March 31, 2020, 12:47:25 pm
I dont mean to be confusing...Basically, That tube may not be your best bang for the money, It most likely has seen a hard life, If you look at it close does it have an image burned on the screen?, And most likely the phosphorus is faded to giving it a faded look, not a dark grey like a healthy tube, And if so, the color guns (inside the tube) should be cleaned, balanced,  and short tested with a rejuvenator for optimal color , https://www.youtube.com/watch?v=_kgy7CCsEBQ  Here is a fun vid on the subject if you are curious ...Just saying 13" TVs are actually easy to find, as they were uncommon for arcade swaps and hacking them is not really all that hard.
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on April 01, 2020, 06:53:17 am
Good morning all, Jen thanks for that great video. I had to idea that such a device existed. If I did this for a living or even a serious side job, I would definitely have that device in my shop. Yes, my monitor definitely has a burned in image on the screen and most likely suffers from all those above symptoms you mentioned. Once I have this game up and working again, I just might take this monitor to a repair shop and have it cleaned and balanced. Iím sure it needs it. If further attention is needed, or as an alternative, Iíll have to keep my eyes open for a color 13Ē TV monitor. Had no idea that they may still be around. Since Iím really enjoying this restoration project, I would definitely consider the challenge of swapping out my monitor. But, one step at a time. I ordered the flyback yesterday and hope to have it installed by this weekend. By then, the rest of the parts should also be restored. I canít wait to see the results of those efforts. Iíll keep you all posted.  :)
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on April 03, 2020, 06:50:32 am
TGIF! Well, those parts came in faster than I had anticipated. The new flyback and all the caps from the cap kit have now been soldered in place. To be honest, Iím still not completely comfortable with some of the replacement caps from the kit. Like Jen said, it could be my OCD kicking in, or just some common sense. Some of the replacements were so far off itís scary. I just hate to assume that thereíre all correct. Does anyone know definitively what those exact replacements should be? Someone must have a printout of the original caps on that GO7-FBO board. If you take a look at Reply 263, the caps that Iím concerned with are the ones that do not have a green dot next to them. Thereís Just the 7 of them. Iím really not even concerned with C520 either. Just: C303, C504, C517, C407, C403, C411 and C518. That pic from Reply 263 above shows my cap values that were originally on the board and the replacement values that I blindly soldered in. C303 is a good example of how far off that replacement was: from 10uf @ 250V to a replacement of 22uf @ 50V. A different micro farad value and a drop in voltage. I have a feeling that a cap replacement was done years ago and that person had a need to clean out their junk drawer of unused caps. C518 is another good example. 220uf @ 50V to 47uf @ 50V, Really! Should I be concerned? Any replyís? Have a great weekend guys and stay safe!!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on April 03, 2020, 07:25:19 am
http://arcarc.xmission.com/PDF_Monitors/Electrohome%20G07%2013in%20and%2019in%20Color%20Raster.pdf (http://arcarc.xmission.com/PDF_Monitors/Electrohome%20G07%2013in%20and%2019in%20Color%20Raster.pdf)

Isn't this the schematic?
Can you walk through the parts list and compare to this? 
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on April 03, 2020, 02:10:16 pm
perkins, I have that list as well. Actually, there was only one value on the list and that was C411. The value on that schematic shows 100uf @ 160V. Isn't that funny, that one doesn't even match the one in my cap kit. That's why I so concerned. Have you seen any other information out there showing the values of the caps? But I think for that one, being that the 250 volts is a higher voltage than the 160, I think that one would be ok. Thanks for looking for me!
Title: Re: Atari Centipede Cocktail table game has no power
Post by: bperkins01 on April 03, 2020, 02:19:32 pm
I don't know much of anything about that monitor..   I would think (hope) the schematic matched..  if it doesn't - then that's a bigger issue.
I think you know - replacing a cap with equal capacitance is ok - high voltage rating is a bonus.   Just don't use a lower rated cap.  (which is on their instructions)

After that..   :dunno

Hopefully you can match things up...
Title: Re: Atari Centipede Cocktail table game has no power
Post by: vapuser on April 06, 2020, 06:53:05 am
Good morning all, after installing the Flyback the other day, I noticed a bracket of some sort on the coil. The bracket seems to have a solder type location on it where you could solder a wire to it. Please see pic below. There were no instructions that came with the flyback that referenced this bracket. Is anyone familiar with this? Is this a grounding bracket? Just guessing.
After making another round through the circuitry, I noticed a few more problems.  Two of the metal oxide resistors were out of spec. R904 is one of them. Itís rated as a 10K 2W 5% type resistor. It read 4.9 K. Also the R421 - 12K resistor was off as well. It read 8.73 K. Also noticed that my Large fuse (F902) was blown. Also doubled checked the H/Out and the voltage regulator transistors again and noticed that the H/Out was shorted. I think these additional casualties were caused when I plugged in the unit prior to installing the new flyback. I think once these parts are replaced I should be good. Iíll give another update at that time.