What's new

mathewbeall

Champion
Joined
Nov 6, 2017
Messages
1,671
Reaction score
1,198
Location
Mission Viejo, CA, USA
It died over the weekend - I just ordered a centipede->JAMMA adapter so I can take the board home and see if the board died, or something in the cabinet.

If something on the board died - I am hoping it's a capacitor or something easy! :)

More later as I troubleshoot.
 
As with all Atari pcbs of that era look for burning on the edge connector.
 
I pulled the board - no cap's look like they have exploded.... the red LED does light up on the board, and there is a sickly sound coming from the speakers, and then nothing happens. On the edge connector - the far right/top connector of the larger connector which connects to the LARGE ground around the board does have some heat discoloration - I will check continuity later.
 
As with all Atari pcbs of that era look for burning on the edge connector.
As Mitsu mentioned, very common.

Also check the socketed ICs they can come loose from moving a cabinet around. The size of the board and side mount does tend to flex even fully mounted. If there is heat discoloration as you said, indeed check continuity on your Gnd and voltage on your rails.

Does it play blind at all? Another common fix I've done if it has the original G07 is the RGB Sync input plug has cold solder or broken joints on the chassis. Which can play blind or has an intermittent connection. Can always wiggle that video harness and see if it displays.
 
it doesn't appear to play blind - as the one player and two player buttons weren't blinking - but solid...
 
Good news (I think) - the board fired up at home just fine with the JAMMA adapter board, so I am guessing something in the cabinet (assuming power) isn't quite working right...

I will have to start digging into that, and see what the service manual says.
 
Glad to hear it's still living!
 
Wait, did you do any power readings coming out of the PSU?

I didn’t see you mention measuring voltages. That’s one of the first things you should check!

with Atari PSU blocks, they have a large capacitor usually referred to the Big Blue.
they are known for going bad, especially after this long. There are replacements available.
I would strongly recommend checking your voltages coming out of the PSU block, then at the test points on the game PCB.

Second to checking voltages, look for cold solder joints on all connector headers going to the board. If you find any, make sure to reflow them by removing the old solder and replacing it with new. Don’t just add new solder to the existing stuff.
 
Thanks @opt2not - I didn't check any voltages yet, the "easy" part was first take the board home and see if it fired up on my test bench.

Sounds like first check voltages on the power brick, and then move to the A/R board. Off to do some googling!

Matt
 
I'm in this same predicament. Although I tested the fuses 3 out of the 5 were bad and got a recaped psu for good measure. Just haven't had time to test it all and put fuses in. I dont have adapter for my board though to test it. i picked mine up from an old op as it had been sitting since hurricane iniki
 
Ok - so pin 1 didn't have any voltage on the main power supply - i checked F2 (fuse) - and voila - it was blown.... not exactly sure why it was blown - but I will order some new fuses and give it a shot.
 
Ok - so pin 1 didn't have any voltage on the main power supply - i checked F2 (fuse) - and voila - it was blown.... not exactly sure why it was blown - but I will order some new fuses and give it a shot.
I would also order a Fuse Tester (Bob Roberts has one he calls a Circuit Breaker Tester):

cirbreaker.jpg


Info here:
http://therealbobroberts.net/cirbreaker.html

This way you're not wasting fuses. I use this all the time when I'm working on fused boards.

If the fuse is blown, it means something else down the chain has gone wrong. Replacing the fuse isn't going to fix the problem, and will most likely blow again. But having something like this Breaker Tester allows you to work on your board and not go through fuse after fuse trying to debug what's wrong.
 
Great idea! ordered!

They were doing some electrical work in the building over the weekend when this blew - so I am hoping that it was that - I have it plugged into a surge protector now.

Matt
 
Mystery deepens a bit.

As a recap - PCB is fine - take it home, plug it into a JAMMA adapter -> into my HAS, and fires up instantly.

At work - I replaced the fuse, and turn the cabinet on - the red LED on the PCB comes on, the one player/two player led's light up on the front control panel (but don't blink) - and nothing else happens.

I checked all the voltages on the PCB 15v, -15v, 22v, -22v, 5v, -5v - all were within tolerance.

What should I be checking next?

Thanks in advance,

Matt
 
What kind of tolerance are we talking about here?

Early 80's PCBs are a bit more strict when it comes to power.

I'm willing to bet that PSU is failing.

But barring that, take a look at the connection headers and connectors. Look for anything burnt, or cold solder joints.
 
@opt2not I will take new measurements tomorrow - but 5v was 4.7 I believe, the rest were pretty close to the values. When you say PSU failing - do you mean the big blue cap or the transformer, or the AR board above it?

@8bitforlife - no sound coming out from it. Sometimes I get a hum in the speakers, other times not. But I do have it set for no sound on boot - so unless the 1 player select is picked, i wouldn't expect any sound on boot.
 
4.7 on the 5v rail is too low for these old boards.

As for what the component could be, hard to say without further diagnostics.
 
Ok - but since the PCB worked on my HAS at home, then it has to be either the power supply or the AR board - is my logic correct there?

I will take more precise measurements tomorrow and post them...
 
Back
Top