Picked up an Asteroids

In my Asteroids situation, I did some more troubleshooting with my working game vs non working game...

Actually, both games work but I need another working AR board...so need to fix one of my extras.....that can be done....

So, I have a Delflection board problem in the non working game...i swapped monitors around and the 1st game played fine on the swapped monitor...Wiring harness and cabinet thus are checked out and good.

I then swapped out the HV Cage in both.

Suspected broken HV Cage put into known good G05 monitor and the known good monitor continued to work fine, in testing. The not-working monitor continued to not work...and the spot killer remained on, with no picture. But with neck glow.

So, I am down to deflection board.

I might just swap the deflection boards out, just as a 100% precaution but I think its going to be the board...I already had it capped but maybe we missed something on it.

I think the fuses checked out good too...but will check them again to be sure.

Anything special I should look at on my deflection board?
 
I'm mostly just afraid of the AR or something having dirty power and frying all the ram again. Unless they were fried from a power surge in the first place. I'll probably just order everything anyways just in case and that way I'll have it on hand.

Security is the man, I already have $100 in my cart for various stuff I'm working on. I'm just waiting on a few sales to be picked up so I can pull the trigger.

You really don't need to cap the AR IMO, unless the caps have been physically stepped on (and even then they often still work, LOL). Atari used really good caps on them, and it's not really worth the cost or work (or risk of messing something up) to replace them, as they don't really go bad.

The only things that typically go on the AR's are the 2N3055 bottlecap transistor (the one in the middle in the big heatsink). You can also replace the 5V adjustment pot if you want, which is a 1K. Best to keep the rest of it original. (If it ain't broke, don't fix it.) Also, reflow all of the other components' solder joints, as they like to loosen up on the Asteroids AR's.

Also, if it's an AR-I-01 (i.e., the normal one for Asteroids), note you will measure around 6.0-6.4V on the 5V test point, if you measure it without the game board connected. This is normal, and it will come down to 5V once you plug the game board in. Atari changed the designs of the AR's so the later AR-II's don't do this, but the Asteroids ones do.

For the frame transistors, they're 3716 and 3792. Two of each. But you should only replace them if they are bad (in which case your delfection board probably also has issues.) Look up how to test them. (Or download my 6100 PDF guide, as you can test them the same way in the b/w vector monitors, and the guide explains how:)

https://forums.arcade-museum.com/showthread.php?t=404600

If you replace them, you should use new silicone (silpad) insulators, instead of mica and thermal grease. The silpads are easier to use, less messy, and don't use grease. You want ones like these:

https://www.digikey.com/products/en?keywords=SP400-0.009-00-03


Security0001 should have everything you need.
 
I'm mostly just afraid of the AR or something having dirty power and frying all the ram again. Unless they were fried from a power surge in the first place. I'll probably just order everything anyways just in case and that way I'll have it on hand.

Security is the man, I already have $100 in my cart for various stuff I'm working on. I'm just waiting on a few sales to be picked up so I can pull the trigger.



What happens is the 2N3055 shorts, and sends 12V directly to the game board, and kills the RAM. It's not the caps. The RAM can also fail for other reasons, even just from being old.

It's generally a good idea not to shotgun parts on these boards, as you're more likely to create new problems, versus fixing ones that may not even exist. Most issues with these are known and can be troubleshot pretty easily, with basic tools saving you time, money, and headaches.

I'm happy to walk you through the steps to get your game running here, if you want to take it step by step. All you need is a DMM.
 
What happens is the 2N3055 shorts, and sends 12V directly to the game board, and kills the RAM. It's not the caps. The RAM can also fail for other reasons, even just from being old.

It's generally a good idea not to shotgun parts on these boards, as you're more likely to create new problems, versus fixing ones that may not even exist. Most issues with these are known and can be troubleshot pretty easily, with basic tools saving you time, money, and headaches.

I'm happy to walk you through the steps to get your game running here, if you want to take it step by step. All you need is a DMM.

That makes sense, all my voltages are good so that must mean the transistor is good. The ram probably just went bad from age, it spent at least 10 years sitting in a hot ass South Carolina barn before I got it so that didn't help matters either. What about the big blue?

I'm most likely going to order everything anyways just to keep on hand, it'll get used sooner or later
 
That makes sense, all my voltages are good so that must mean the transistor is good. The ram probably just went bad from age, it spent at least 10 years sitting in a hot ass South Carolina barn before I got it so that didn't help matters either. What about the big blue?

I'm most likely going to order everything anyways just to keep on hand, it'll get used sooner or later


Yes, just sitting is actually the most likely cause. Most of the dead boards I get off of ebay and repair end up having have RAM issues. And you can tell they've been sitting in a warehouse for a long time, from all of the crap on them. It's odd, but the chips just don't seem to like sitting.

To test the big blue, put your meter on AC volts, and measure from the 10.3V DC test point on the AR to ground. This way you are measuring the AC ripple on the DC supply, to see how well the big blue is doing its job (which is filtering the rectified voltage). You should typically see around 400mVAC or less. (And if you switch your meter to DC, you should see between 12 and 14V DC.) If the AC is much higher (e.g., a volt or more), then you should replace the big blue. Else it's ok.
 
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