Reason System 80 is stupid #84

Lindsey

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I've spent a lot of time working on System 80 but this one really takes the cake. Gottllieb basically designed their game to burn coils.

I'm working on a Gottlieb Force II. It needed all kinds of bullshit which I'll get into another time but I'm down to just 2 lamps not working. Obviously the thing to do is put the game into lamp test and start troubleshooting these lamps. The first thing you'll notice, once I get the game into lamp test is that it doesn't flash all the lamps on and off at the same time. This is not unusual for System 80. I assume they saved code space by just calling the attract mode routines from their test code as the way the lamps flash in test look a lot like attract mode. This in itself isn't a big deal until you add the fact that they're also driving several coils in the game with lamp driver circuits (basically using the lamp driver circuit as a pre-driver for a big-ass transistor mounted under the playfield). So rather than have these lamp driver circuits not flash in lamp test their code happily energizes these coils over and over again. Even that wouldn't be a huge problem over a short period of time but they're not energizing the coils for what would be a sane length of time, say 100ms, instead the coils are energized for like FIVE HUNDRED milliseconds and start getting hot within a few cycles.

They were kind enough to put a timer on the lamp test so it only runs for maybe 30 seconds but you can just push the start button to start it again. If you didn't know what was happening and ran the lamp test a bunch of times in a row you could easily burn up those coils. I don't think it's a coincidence that one of the two coils that were burnt in this game when I got it were on these kinds of driver circuits.

You can use the lamp test... but a bunch of coils will burn up as a result of running it more than a few times in a row. So you've got that going for you...
 
Is this an 80A thing? My Arena is an 80B and this sort of thing isn't an issue, there's a completely separate coil test and no coils fire on lamp test.

Though the lamp test is fucking annoying as it cycles through sets of lamps that are in different points on the playfield very quickly, and to see a lamp out for certain you have to watch it more than once to be sure. There isn't even a manual mode...that's the worst part.
 
This may/may not help. If I'm testing a certain lamp or even a coil circuit, I've found taking a jumper wire and connecting one end to ground,and than touching the other end to the corresponding transistor(MPS-45) on driver pcb will activate circuit. This way, I can control how long it is activated. When you touch the grounded jumper wire to the transistor metal tab, this will "fire" the transistor.
Aaron
 
This may/may not help. If I'm testing a certain lamp or even a coil circuit, I've found taking a jumper wire and connecting one end to ground,and than touching the other end to the corresponding transistor(MPS-45) on driver pcb will activate circuit. This way, I can control how long it is activated. When you touch the grounded jumper wire to the transistor metal tab, this will "fire" the transistor.
Aaron

Thanks for the help. That's exactly what I did once I realized the lamp test wasn't going to be much help. I hoped to check the sockets, etc... with the lamp test but I guess that's too much to ask ;)

The challenge of working on Gottlieb is something I actually enjoy but it does get a little annoying from time to time with the combination of wacky design and total lack of manuals online. I usually get by with what paper manuals I do have for System 80 but for this game with it's 15 memory targets powered by lamp driver circuits the actual manual would definitely save some time. I've already had to manually trace a bunch of stuff.

But... That's Gottlieb!
 
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Is this an 80A thing? My Arena is an 80B and this sort of thing isn't an issue, there's a completely separate coil test and no coils fire on lamp test.

Though the lamp test is fucking annoying as it cycles through sets of lamps that are in different points on the playfield very quickly, and to see a lamp out for certain you have to watch it more than once to be sure. There isn't even a manual mode...that's the worst part.

This game is System 80. Not A or B. I know what you mean about 80B though. The lamp test sucks on that one too.

Through sheer coincidence I'm working on System 1, 80, 80B and 3 (gottlieb) all at the same time right now. It's been ugly...
 
This game is System 80. Not A or B. I know what you mean about 80B though. The lamp test sucks on that one too.

Through sheer coincidence I'm working on System 1, 80, 80B and 3 (gottlieb) all at the same time right now. It's been ugly...

well....it builds charactor!
 
This game is System 80. Not A or B. I know what you mean about 80B though. The lamp test sucks on that one too.

Through sheer coincidence I'm working on System 1, 80, 80B and 3 (gottlieb) all at the same time right now. It's been ugly...

Ugly ain't the word I'd use,buddy....
 
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