Bally 83F - Cleared RAM - now circuits pop?

[Abe Frohman]

Here's the chain of events:

I had an 83F error, and I followed these instructions:  http://newlifegames.net/nlg/index.php?topic=2333.msg18028#msg18028

Error cleared, everything was great!  Then, for some reason, I slid the MPU out and back in again.  It didn't feel like it was going in correctly, I might have pushed hard to be sure I was seating it in the backplane correctly.  (Did I do it with the power on or off?  i don't remember.)  Upon next powerup I got discombobulated LED displays and no game.  Also, the bottom circuit breaker is popping repeatedly.  I took the board out and noticed that one of the plastic slider guides had come off and was in the back of the MPU cavity.

So now if I pull out the coin in assembly, hopper and mainboard, the bottom breaker pops *and* I hear the machine "hum" and the bill validator power cycling repeatedly.

Any ideas as to what I've broken?

[Slotmaster]

Check the pins on the back of the MPU board to see if any are bent over.

This usually is the first thing I check when the ckt pops.

[Abe Frohman]

Good suggestion; I will.  But the circuit's tripping even without the MPU board in the machine at all.  I'll check the various components on the backplane too but I feel I really screwed the pooch here.

I was reading a similar post by Dinot at http://newlifegames.net/nlg/index.php?topic=638.0

and I feel a lot like we all have at times I'm sure, these things are so logical yet so finicky at times, compounded by me doing stupid things like ramming the board in, probably not turning the power off, etc etc etc...  One of those moments you start pounding your own forehead and talking to (swearing at) yourself saying "why did I do that - stupid, stupid, stupid..."

I've got the same machine (different game) right next to it, I might get brave and do some swapping but like in Dinot's post, I don't want to go trashing more of my games!  I have to walk the line and try to not learn too many hard lessons simultaneously or I'll just get disgruntled 

[Slotmaster]

Ok I understand what you are saying now when you removed everything and it still pops.

Bottom line is you have a short somewhere so I would start by removing the backplane from the equation.

However if you have another machine I would use it as the test machine for your board like you noted.

But if your machine is tripping with no board installed the issue is somewhere else now.  I would start with the backplane.

[jdkmunch]

What type of machine it it? 5000,5500,6000?

[a69mopar]

I would first look through the wires, with the machine unplugged, for a short, then go from there.

w

[a69mopar]

Jonathon had a good question.  What model is it? year?

Thanks,
Wayne

[Abe Frohman]

I had to check; it's a 5500.  Didn't catch the year though.  For some reason 1996 comes to mind?  I have the hopper, coin in and MPU out and the bottom CB trips.  The BV assembly is still plugged in but sounds like it's running normally.  The reels are still plugged in, as are all lighting and door connections, etc.

I checked the backplane board and there's nothing at all there except two female sockets, so no pins to bend etc.  The backplane has no logic or components on it below the MPU cavity either, just harness connections.  So now I'm suspecting, and in fact hoping, that it is only a blown power supply I guess.

I wish the G1 Android phone had a flash, had to use a fashlight to get a picture of the backplane...

Does anyone know specifically what that bottom breaker does?  I didn't get a chance to check its voltage, etc.

[a69mopar]

I would check the power supply, it's either the 7.5v ac or 21v ac. The power supplies back then had some issues.

Thanks,
Wayne

[jay]

You might also check the candle wiring. This is a common short. Wire gets stripped due to moving other stuff around and then fwvess-zap a fuse goes.

[Abe Frohman]

I didn't touch the candle wiring but I will definitely check it, I know sometimes the slightest breeze...

When I get home tonight I guess I'll take a page from Dinot's post and try the power supply from my only other Bally.  Of course I'm worried that whatever blew that one will blow this one, but the risk is about the same if I swap any other component...

As Jay's tagline says - if I can't afford to lose, I can't afford to win?  It it doesn't work, I was stupid.  If it works, I was brave - not necissarily smart!

[Abe Frohman]

*BING*  For those of you (and I) that said "Power Supply" you were correct.

I put the board into another machine first - OK.  Then the other power supply into suspect machine - OK.

So now the patient is back up and playing, and I need a supply for my other machine.


I love re-learning lessons I already learnt - at a price...