Asteroids Restoration (hopefully:)

[Crayola]

I picked up an Asteroid cabinet from a family that had it in their basement for
the past 20 years. Its in really good shape for a 30+ year old cabinet.
It doesn't work but I am hoping it is just a power supply or fuse problem.
The owner told me the monitor just didn't come on one day but it still played
blind.. then a few weeks later it stopped making sounds and nothing lights
up. The cabinet has no water damage and only one corner has about 1/2"
worth missing from it. Everything looks original to me but that's why I am
posting pictures for your expert opinions.  

I looked high and low for the serial number but couldn't find it.

Probably the biggest cosmetic issue with the cabinet is one of the side art
has specks of paint all over it.. like someone was very careless with a white
paint brush. Do they make a stencil for asteroids?  

So I guess my first goal is to pull the power supply then replace the big blue
and make sure all the voltages are correct. Should I get an oscilloscope? All I
have is a decent multimeter and a great soldering station. What tools do y'all
use to troubleshoot issues with boards and monitor?

Crayola

[Crayola]

More pictures for your viewing pleasure.

Crayola

[Spyridon]

Stencils are not available for this game, but new side art is (the cab was not originally stenciled)



You shouldn't need an oscilloscope to get the game up and running but they are useful to help determine if you have a monitor or board issue.  You can hook the scope up directly to the x and y output on the board.




 
(sorry for the poor video quality, it was done using a cell phone)

[Spyridon]

So I guess my first goal is to pull the power supply then replace the big blue
and make sure all the voltages are correct. 

Definitely start by checking the voltages.

What tools do y'all
use to troubleshoot issues with boards and monitor?

I've found the best tool to be the people on this board.  Very helpful and very good information. 

[RayB]

Refer to the troubleshooting tips I posted in your other thread.

[Crayola]

So good news.. I started with the fuses on the monitor and power brick..

I found two bad on the power brick using the multimeter.

Can I get 7-amp 250v 3ag slow blow fuses somewhere local?
Auto parts stores? Those are all 12v..I think.

Both the 7 amp fuses were blown on the fuse block. Looking at the schematic.. all the juice for the
PCB goes through those.

When I power it up the monitor neck glows and the red LED on the monitor board lights up.
Zero output on the screen but I wouldnt expect any since the monitor isnt getting signals

The coin doors light.. those run on 6.5 volts it appears.. odd voltage for a small incandescent light.

Not sure why the marquee isnt lit.. probably something dumb like a bulb or a starter.
Going to change that next.

.. Yep bad starter and bulb. Replaced both and it lit right up. I checked out the marquee. Its perfect from a paint job point of view. All the paint is there and its vibrant. However on the other side the plexi has some scratches I can feel with my fingernail. Would novus 3 work on those? They aren't gouges.. just scratches. Any suggestions to remove them otherwise?

So how can I tell what version AR board I have in this thing? I cant find any markings
that say AR 1 to 6. I want to buy a rebuild kit from Bob Roberts.

The cabinet number is 24,619 BTW. Found it stamped on the AR board and the monitor chassis

Crayola

[Crayola]

So I bought a rebuild kit for the AR board and power supply from Bob roberts.. That guy rocks!

I was able to find a really good assortment of fuses at home depot. fast and slow blow.

I replaced the fuses and powered up. I coined up and blammo! The game is alive! Although the
monitor is not. I can totally play the game blind and everything seems to work well.

Now to tackle the monitor. I already checked all the fuses. The neck glows and the red light on
the deflection board is lit. I also noticed that once I replaced those power supply fuses and powered up, there
was a small speck of light in the middle of the monitor. If fact looking really carefully... there is
actually a tiny spot burned in right where it is (visible when the monitor is off). After I powered
off (quickly) I noticed it took a while to go away.. faded out slowly. I guess this is the spot killer
I have read about? What I read said to trun up the brightness all the way to tell
which part of the deflection circuit is having a problem. So I found the brightness and turned it
all up.. nothing.. nadda. A big bright light in the middle but no faint game image. I'm guessing both the X and Y
is bad on the deflection board or the game isnt sending a signal.

The monitor is a Atari Quadrascan 92-047.. thats  an Electrohome G05-802 right?

Any suggestions on where to get next?  I've never messed with monitors before so this is
new territory but I know what and what not to touch (aware of danger).

Crayola

[Crayola]

So I found tha manual for the monitor at

http://arcarc.xmission.com/PDF_Monitors/Atari%20Monitor%20TM-151%20Issue%203%20Electrohome%20G05-802%20G05-805%20Monochrome%20XY.pdf

Look like the LED being on on the monitor board isnt a good thing. It indicates that the spot killer is active
and it thinks no signal is present.

I'm guessing back to Bob roberts for a cap kit and discharge tool at this point.

Crayola

[Crayola]

I test the PCB and AR board a bit. The X/Y test points on the PCB board show up and down movement
+5/-5 so that looks good. Looks like the board is sending a signal. I am going to check the harness
next for X/Y movement. The AR board is showing 5.3v and 11.4v at the sense points.

I need to find someone in NJ with an oscilloscope I can use to verify their is good output from the PCB.

Know anyone in NJ who might be able to help?

Crayola

[Crayola]

I also checked the Z sense point on the PCB.. it was flucuating from .6v to .8v but mostly staying
at .6v I am not sure if this is good or not but at least the is output and voltage movement
so I assume its good.

The KLOV guys suggested Reflowing the deflection board. I and going to wait until the cap kit
kit gets here from bob roberts and do it all at once.

Crayola

[jennifer]

  A discharge tool??? That sounds kinda fancy..... Two long shanked screwdrivers [and maybe heavy gloves] will short those pins to
the frame......careful however that can really...really...really, hurt.
    sounds like a cap kit or flyback is the trouble.

[Spyridon]

  A discharge tool??? That sounds kinda fancy..... Two long shanked screwdrivers [and maybe heavy gloves] will short those pins to
the frame.
   

That works fine for raster monitors, but not really the best way on a vector monitor.  You'll want to have a resistor on there to slowly drain the monitor or better yet, a HV probe.

[Crayola]

Bob Roberts page says that the resistor is not needed. I have to imagine
he has worked on plenty of vector monitors in the past.

http://www.homearcade.org/BBBB/sb.html

Of course dont trsut me.. this is my first time working on a monitor.

Crayola

[jennifer]

    I"ve never hurt one, been doin" it like forever..... But in all fairness, what Bob says goes, he won"t steer you wrong.