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Author Topic: Star Wars Cockpit......SHE LIVES !!!!!  (Read 69065 times)

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shardian

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An oscilloscope it exactly the same thing. However, normally, the movement on the x-axis is determined by a timing setting on the scope. So the electron-beam goes from left to right. When signals are supplied to the Y input, these signals will control the Y movement of the beam. In that way you can see the signal as it moves in time. (f.i. like your heart-beat on a cardio machine, exactly the same thing).
Like this:




The bold section above is what was keeping me from believing what you were saying.

I would love to see an example of an oscilloscope playing a vector game image. That would be very cool.

Level42

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I may be able to give it a try next saturday. Remember that I will only get one of the three colors on an oscilloscope. I do need a second probe though. You normaly need only one, but of course since I will be supplying two signals at the same time I will need a second.....hope I can find one....

ChadTower

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Vector pong on a scope

That's all I can find from here but of course my work proxy kills most game sites.  I've seen Star Wars on a scope in person... it's really just a little vector monitor once you get it going right... of course, only in one color.

SavannahLion

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I would love to see an example of an oscilloscope playing a vector game image. That would be very cool.

Not exactly a vector game PCB driving an oscilloscope but ZVG is an example of a board driving an oscilloscope as a game screen.

Level42

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I would love to see an example of an oscilloscope playing a vector game image. That would be very cool.

Not exactly a vector game PCB driving an oscilloscope but ZVG is an example of a board driving an oscilloscope as a game screen.

Yes, and so is any other Vector game PCB.
 

:D


ChadTower

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A vector monitor is really a fixed rate oscilloscope with a couple other little controls (intensity, alternate colors, etc).

Level42

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Something completely different:

Anyone know a source for that ribbed T-molding used on this baby ? The

ChadTower

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In the movies, when someone stops a sentence in the middle like that, it's because someone jabbed a spear through their

Level42

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Hahaha, no worries, I'm alive and well.....don't know what happened....

to end the sentence:

The "usual" places don't have it.     That's all....

By the way, I just received my order of BU406D's....10 of them, should be enough for the rest of my life :P

I found a cheap and reliable source for them in Germany (don't worry, sits is in English too):

http://sh-halbleiter.de/final/index2.php?sp=2

This is a direct link to the BU406D:
http://sh-halbleiter.de/final/index2.php?sid=33ce027bf470aab03dac6212ac931d6b&tp=1&kn=0&sp=2&g1=0&g2=0&g3=0&ti=&ms=0&od=0&an=&bm=0&ch=&st=bu406d&x=0&y=0

I received them very fast after payment and very well packed....

Also went to my local electronics parts dealer for the "easy" parts. Got all the suspected dead parts and a few more, like all the caps so I can replace them wether they are bad or not.

I did a check comparing my original BU406D to the new one's. These baby's are hard to check because they have a built-in diode and resistor on top of the transistor. In diode test both the old and new one seem to be responding the same, although the old was showing a 0,63 V across basis and emitter and the new one only 0,19V........

I wonder if I should give it a try to replace the defective parts and see if my "ded-read" HVT still lives....


« Last Edit: July 19, 2007, 11:55:33 am by Level42 »

ChadTower

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.19V is too small across a diode... probably not completely dead but leaky, particularly if the PN junction is mostly worn out... maybe from too much time blocking current in the wrong direction, or too many surges... take a peek at what in the circuit would be feeding that diode from the opposite direction, see if those parts check out.

Level42

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Uhhmmm, the 0.19V is on the brand new BU 406D's.......  ::)



ChadTower

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Oh... maybe I'm picturing something different from your description.  Hrm.  Still, junction drop from any single diode should be in the 0.7v range, yes?

Level42

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Yes, you're right. The BU406D is basicaly a transistor. The D stands for Diode and this is added to it inside.

Strangely, no datasheet I've found seems to indicate this. However, Atari's schematic of the Amplifone HV monitor does. I've included a small part of it...as you can see it is driven by the step-up transformer and the BU406D then drives the HVT. If (or better when) the HVT fails, it will VERY likely take out (at least) the BU.

Lots of people have been replacing it with a BU406 (without the D) and this is a big problem according to all the docs I've read.


By the way, I wrote that the diode was across basis and emitter, but that's incorrect as you can see. It's across collector and emitter.

ChadTower

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Good to know.  I have 3 vector monitors I need to pull and fix.

Level42

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Good to know.  I have 3 vector monitors I need to pull and fix.
3 !!!

Which brands/types ?

Singapura

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Stories like this are more addicitive then a soap on tv! Can't wait for the end result.  ;D Good to see that there are still good finds in the Netherlands, especially my all time favourite sit-down game. I remember playing it in the arcade in Veendam (of all places). Here in Singapore there's little chance of running into gems like this  :-[
Wish list: Galaga, Pacman, Pooyan, Star Wars cockpit, Gauntlet, Tron

And the Lord spake, saying, 'First shalt thou take out the Holy Pin. Then, shalt thou count to three. No more. No less. Three shalt be the number thou shalt count, and the number of the counting shall be three. Four shalt thou not count, nor either count thou two, excepting that thou then proceed to three.

ChadTower

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Which brands/types ?

One is a Sega... the other two, not 100% sure off the top of my head, one in an AD and the other in a Star Wars.

Level42

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Which brands/types ?

One is a Sega... the other two, not 100% sure off the top of my head, one in an AD and the other in a Star Wars.
The AD is probably an Electrohome G05. The Star Wars probably an Amplifone 19" ? Although many Amplifone's have been replaced with WG 6100's....

ChadTower

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The AD is probably an Electrohome G05. The Star Wars probably an Amplifone 19" ? Although many Amplifone's have been replaced with WG 6100's....

I think you're right on the AD, but I haven't even looked into the SW yet to see. 

Level42

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WHAT ?? And this from the guy who urged me to check the CRT's diameter  :laugh2: :laugh2:

ChadTower

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Heh.  That SW is a serious project that pretty much got stowed in the shed and put behind a buttload of stuff in the queue.    Much water damage to the cab, I didn't even try to start it, I just checked to see that everything was there and put it away.  It's 19", that is all that really matters.

ArcadeMaze

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« Last Edit: May 15, 2008, 10:34:17 pm by ArcadeMaze »

Level42

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Well, I guess vectors are about the most replaced monitors in arcade games because of all the well-known reasons....and operator's probably hoped to get a more reliable one by replacing the original with another brand.
But it could also be that manufacturers switched because of supply problems.

Level42

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By the way, about the 19"/25" debate: I've studied the SW cockpit operation and parts manual and it simply ONLY mentions the 25" there.  Both in the drawings and parts listing.

This, combined with the fact that all pictures I've seen on the net of SW CP CRT's are 25" makes it safe to conclude that the Cockpit has ONLY been equipped with 25".

Level42

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Hah, I only discovered yesterday that my SW CP had made it to the news page !!! I already wondered what the all-of-a-sudden high rates of view on the pictures came from. Thanks Saint, I feel honoured !  :cheers:

OK. Let's face it, in this hobby and on this forum it's great to report about your successes. However, sometimes you f.u. in the proces. It's normal, we're only human after all (from a well-known Level 42 song :) )
However, sometimes it's REALLY embarrassing how stupid you can be. So first I thought not to post this, but then again... what the heck:

Yesterday I found a couple of hours to work on the CP. Now, as you remember, the cab is stored in a good friend's shed so when I go there I have to bring my stuff like docs, equipment etc.

I started working on the HV-board, replacing all the suspected/defective parts. It turned out that only the 7824 was really defective and of course the 50 Ohms resistor that burnt out. However I still replaced the 7924, the 1N4001 diodes, the other resistor and all the elco's ("caps"). However, for some stupid reason I had de-soldered the resistor wire and the 1N4001 diode wire the last time I worked on it.

For those who don't know, these diodes and 50 Ohms resistors were added to the design of the HV board later, it's a factory mod. So there's no clear indication on where goes what (The diodes are on the tracks side of the PCB).



So I thought I had figured it out and remembered how things were connected.....so I soldered away. (I regretted very much not printing out the picture I took from the track-side....should have prevented this mistake)

Then it was power-up time, and of course I was checking the resistor as soon as it powered up, and I freaking almost burnt my finger, so it was again/still heating up like nuts......
So I thought something else must be making this happening, a part I hadn't replaced. (FYI I hadn't put back in the BU406D which I had removed before. This way, there is no drive to the HVT, so the HVT can't blow up the first stages of the circuit....

I looked at the schematics and decided that only a couple of transistor could cause this, but all of them checked out fine.

Then I had another look. Sadly, the 50 Ohms resistors are not represented in the schematics, so I looked at the great Amplifone FAQ doc by Michael Kelley (http://www.gamearchive.com/Video_Games/Manufacturers/Atari/monitors/amplifone/amplifone_faq_1_2.pdf) and there it was: I had connected the resistor to the wrong pins...DUHHHH, I was directly feeding the output of the 7824 into the 50 Ohms resistor, no wonder it got hot !!!! (It should have been across pins 1 and 3 of course....!)

I'm not sure if I fried the 7824 by doing this....I had little time left. I did correct the mistake of course and now the resistor stayed cool. Then I decided to try and put in a fresh BU406D....
Fired up and, no picture.......I bet the HVT is dead, as very much expected. I ordered one, gotta wait for it to arrive...

Sorry if this all gets very technical.....bottom line is to check and check again....I'm embarrassed that this happened to me, being en electronics professional, but at least there is no permanent damage. "The force is still with me" when I throw in a coin, and I can hear the deflection sound changing during attract mode, I hope that's another indication of the game PCB's still working OK :D

ChadTower

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This, combined with the fact that all pictures I've seen on the net of SW CP CRT's are 25" makes it safe to conclude that the Cockpit has ONLY been equipped with 25".

Maybe in Europe?  I've seen a few cockpits, a couple "completely original", and I've only ever seen one with a 25".  Hard to say, really, but I can't imagine ops throwing away their 25" amplifones when the 19" aren't much more reliable.

Bummer on the mistake but it sounds like it was more time wasting than physically damaging.  If that's all that happens, the project is going well.  Make it as technical as you'd like... I enjoy reading it and have a SW to rebuild myself.  The only thing I couldn't follow is that I am unfamiliar with most parts by number.

To take a guess - 7824/7924 - 24 volt regulators, positive/negative respectively?

And clean up that ancient flux, man!   :laugh2:

Level42

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But were they 19" Amplifone's ? Maybe they were WG's ? I'm not saying I doubt what you saw, but AFAIK Atari's manuals were universal(global). They often mention differences between the US and Irish built cabs (like f.i. the coin mechs, the manual says that only the Irish were equipped with two.....) So it would be very likely they would mention both 19 and 25" if both were used in the CP's.Atari was very thorough on the manuals. My Centipede still had the original manual and also mentions both US and Irish versions...

Then again, who knows, maybe they ran out of supply on the CRT's or something like that...

Maybe the 7824 got damaged, but I got an extra for both of the regulators of course...

Yeah, I guess I wrote too much from a point that people who have read the Amplifone Faq and/or read the Amplifone manual.

Indeed 7824(+) and 7924(-) are voltage regulators. The BU406D is the transistor that drives the HVT.

I just got a mail from Mark Shostak from Cinelabs and he explained me that the rule of thumb on the HVTs is that if it's red, it's dead. Every red HVT he has seen was dead. The only way he could get a working one was by asking lots of people, and then he finaly found ONE working.

I ordered his replacement HVT. I think he's the only source for Amplifone Replacement HVT's now. Timing is perfect, since they are only available from february this year...There used to be also Wintron HVT's, but these were really expensive (200 bucks) and you had to do some mods on the wiring afaik. Cinelabs' replacement is a drop-in, no "hacking" around...check it out: http://www.cinelabs.com/amp/

I borrowed a HV probe from my uncle who has been in TV repairs for years (Running In The Family ? (Another Level 42 smash-hit :P)). Gave it a test drive yesterday on my Galaxian monitor (=Philips TV) but it overloaded my Fluke...aparantly there's not enough resistors in this probe  ::) No damage to the Fluke, but no reading either. Only after I turned the cab off, the range lowered enough to give a reading....

Anyway, I got this from e-bay


Should be on it's way now. Nice to have an all-in one unit, and I've got two more cabs with defective monitors ahead of me, so I figured it would make sense to get one.

So now I just have to wait for the HVT to arrive....but I can do some cleaning work on the rest of the cab...

How should I get rid of the flux ? As you can see, most of the pins having it are from the HVT and since I will replace that anyway, brand new solder will be used :D I already reflowed the most dark looking solderings but that was after this pic was taken.....


ChadTower

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I usually just use rubbing alcohol to get the flux off.  It probably doesn't matter there but I would imagine it does present a small heat issue in other places. 

Is that an HV probe?  I've never actually used one.  I do have a whole bunch of CRT type testing equipment I got off Freecycle a while back... even a very nice CRT tester that I haven't had the occasion to use yet.

Level42

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OK, thanks for that tip. Yes that's an HV probe with internal voltage meter, so you don't need a seperate DVM for it.

I will battle the heat by installing a really big fat fan. This is suggested in the Amplifone faq and sounds like a good idea to me. I'm using a really big one because it will be able to run on a slow speed so not make lots of noise (although SW CP already has a really big fan) AND because I got it in a "package deal" in which I got a lot of arcade controls in one lot. Perfect for this use....


ChadTower

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Cool.  Literally.

I'd consider adding two fans... one blowing in, one blowing out.  Maximum airflow.  They can both be slow and quiet that way.

Level42

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I'll mount the fan directly near the HV pcb. Should be enough.

By the way, can somebody report this guy to the Mame devs/Ebay ?

http://cgi.ebay.nl/ATARI-CLASSIC-1984-STAR-WARS-ARCADE-GAME-PLAY-IT-NOW_W0QQitemZ140140903121QQihZ004QQcategoryZ50277QQssPageNameZWDVWQQrdZ1QQcmdZViewItem#ebayphotohosting

Level42

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Two pics I made last saturday BEFORE I exchanged the bad parts. They show the burned resistor (on top, in the middle) you can see how it blackened the PCB. The right side of the first picture is normaly up, you can see the travel of the heat/smoke.....but all this damage was already there when I bought the cab.

When I removed the resistor, the PCB under it had a bright white spot, it totally burned away the blue color !


« Last Edit: July 25, 2007, 12:52:21 am by Level42 »

ChadTower

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Nice.  Keep the work going on this, can't wait to see it alive.

Level42

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Yeah, I will do some work this weekend (although not on sunday, as I will be visiting DarthNuno's lair, can't wait !!!!)

I just PayPalled the money to Cinelabs for a replacement HVT.....so I will remove the dead-red and then wait......well, I can start to do some cleaning of course :)

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Quote
although not on sunday, as I will be visiting DarthNuno's lair, can't wait

Say Hello to Bruno from me  ;)

have fun  :cheers:

Level42

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Quote
although not on sunday, as I will be visiting DarthNuno's lair, can't wait

Say Hello to Bruno from me  ;)

have fun  :cheers:

Will do, but I didn't look right on my agenda. I will be visting Bruno NEXT week (aug. 5)....sorry for any confusion Bruno ! :D

Level42

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While waiting for the HVT to arrive, I'd like to share this website with you:

http://www.jmargolin.com

This is Jed Margolin's website. Jed is the man behind the hardware of (amongst others) Battlezone,  Star Wars, Hard Drivin' and Steel Talons. He worked an impressive 13 years at Atari (Games) !

This site looks boring, but is full of great information. Sometimes very technical, but often also very interesting for other stuff....sometimes you have to read "through" the technical stuff, because interesting facts are spread out in between....


Some highlights:

- Star Wars (this is what I found first on this site): http://www.jmargolin.com/vgens/vgens.htm#Star

- Space War - This is a game proposal that Jed brought with him on his job interview with Atari. Check out the date (last page) !!! He is talking a 3D game, with speech synthesizers, and even mentions the idea of linking them, even through telephone lines. All this in 1978 !!! This guy was really ahead of his time :) !
When you read this, you will easily see which ideas finally made it into Star Wars (and some into Battlezone):
http://www.jmargolin.com/patents/atari1.pdf

- Amplifone Notebook ! This was handed to Jed during the first meeting between Atari and Amplifone. Take a look if you have an Amplifone vector monitor ! This shows that HVT's were one of the main products of Amplifone BEFORE Atari got involved.....wonder how they survived, or was the dead-red just bad luck ?  Very worth taking a look at, in a time it's hard to imagine that a factory like that was NOT in China  ! http://www.jmargolin.com/xy/ampnote.pdf

- The secret life of XY monitors: http://www.jmargolin.com/xy/xymons.htm
- The secret life of Vector Generators: http://www.jmargolin.com/vgens/vgmenu.htm
- TomCat - Atari's last XY game (never released) http://www.jmargolin.com/tomcat/tomcat.htm
- Atari Telephone directory 1983 :D http://www.jmargolin.com/history/ataridir.htm
- http://www.jmargolin.com/vmail/vmail.htm  if you're really bored, there is a TON of e-mail (vax-mail really) stored here that went between Atari Employees. Some things are really boring, something are quite interesting to read !)

ChadTower

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Dammit.  Now I have to read it all.

Level42

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Haha, enjoy :)

Been to my cab yesterday.
 
I de-soldered the red-dead HVT. I wanted to remove the anode-cup on the CRT, but there is some REALLY dirty stuff over it.
You can easily see the area around the cup on this picture:


 I think it's put there in the factory, probably to seal it off completely ? Seems like some clear kit/gel. Really sticks to your fingers. I've never seen stuff like this on other CRTs/anode cups.

Since it will be some time until I receive the new HVT, I decided to leave the cup where it is (so not to open the hole). Don't know why, I just didn't want any dirt to come into it... So I snapped of the wire instead.

I temporarily removed the transitor that drives the HVT (the BU406D) again and powered up. Everything seems OK. I measured the input and output of the 7824, got about 30V in, 27V out. It's not exactly 24V because it's not under load now and also because of the parallel 50 Ohms 5 W resisitor, so this is OK.

The 7924 showed even almost the same voltage in (-30V) as out. I was a bit worried about that, so I desoldered it, compared it in diode check with a brand new 7924 and it's  still fine. I guess it's just that there is completely no load for the 7924 now that it's output is about as high as the input.

Next I got my scope to check if the 555 is oscillating. Took a bit of time to adjust it correctly (my oscilloscope is REALLY ancient, 40 years, and Russian built, tiny 2" round screen :D) but then I could clearly see the block signal  :applaud:
Next i checked if it was present on the last transistor before the HVT driving transistor (Q2) and indeed it was there and of course in a much higher amplitude.
(Regretfully I don't have a second probe to try and get a game picture....)

So, I think my HVT-board is ready for the new HVT to arrive.......can't wait !!!!!!!!

Did some cleaning of the sides and the bezel, steering yoke, CP etc. It still amazes me how much dirt keeps coming off, and how much the looks improve. Of course I used my favorite stuff, DASTY (see the Galaxian No.815 thread).
I forgot to bring my camera so I have no pictures of how it turned out....will do next time. By the way the marquee lighting works great and the marquee looks near mint :D

I was thinking about removing the deflection board and/or the game PCB's to check/clean them, and maybe even re-cap them, but I decided not to move ANYTHING electronic, untill I've got the HV up and running....

Did remove the two ventilation covers to give them a good clean......gotta start somewhere ;)
« Last Edit: July 29, 2007, 05:27:54 am by Level42 »

Level42

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That ded-read looks very nice after a good bath. That doesn't make it less dead though  ::)

Ultra Tuned.....yeah right  :D



  
 

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