Theatre of Magic Backbox GI string question

Bullwinkle

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I have a manual for it, but am having problems locating the appropriate transistors. The 2nd Backbox GI string (pins 2 and 8 on connector J-120) have no voltage.. Pins 1 and 7 show 5.8vac and that string works. I'm trying to find the corresponding transistor(s) to the 2nd string do I can replace them but I don't see where it is in the manual. Can anyone point me in the correct direction or to a schematic that shows what I need?

Thanks

Tom
 
This is the "I'm a moron" post..

I had one string of backbox GI out on my machine as well. I had blown it somehow using my multimeter (What was that spark? Where'd my lights go? DAMMIT!!!) right after I picked up SPace Shuttle. I still don't know what the hell I'm doing with a multimeter, but at least it's broken so I don't have to worry about frying anything else with it...

Anyways, fast foward like 7 months. I finally get around to poking in the backbox trying to figure out what the hell I did. Turns out that someone fused EVERY LINE OF GI IN THE BACKBOX.... why? I don't know. I can't find these four fuses in the schematic, but there they are, right next to the power board on my pin. Goes from the power board, down to the fuses, then over to a connector to the main harness. I guess it was pretty smart in retrospect, but aside from an idiot like me doing something stupid, not sure why you'd really NEED to fuse a GI line that only has 10 bulbs on it!

So I had shorted the GI line with my meter, and it blew the fuse. 35 cent fix. Replaced the fuse, all my GI now works. HELL YES. So, check it out and make sure someone didn't put in some pointless fuses that may be saving you some trouble. ;)
 
This is the "I'm a moron" post..

I had one string of backbox GI out on my machine as well. I had blown it somehow using my multimeter (What was that spark? Where'd my lights go? DAMMIT!!!) right after I picked up SPace Shuttle. I still don't know what the hell I'm doing with a multimeter, but at least it's broken so I don't have to worry about frying anything else with it...

Anyways, fast foward like 7 months. I finally get around to poking in the backbox trying to figure out what the hell I did. Turns out that someone fused EVERY LINE OF GI IN THE BACKBOX.... why? I don't know. I can't find these four fuses in the schematic, but there they are, right next to the power board on my pin. Goes from the power board, down to the fuses, then over to a connector to the main harness. I guess it was pretty smart in retrospect, but aside from an idiot like me doing something stupid, not sure why you'd really NEED to fuse a GI line that only has 10 bulbs on it!

So I had shorted the GI line with my meter, and it blew the fuse. 35 cent fix. Replaced the fuse, all my GI now works. HELL YES. So, check it out and make sure someone didn't put in some pointless fuses that may be saving you some trouble. ;)

hahaha...well, I guess I didn't check to see if there were any additional fuses back there but will do that. you never know. thanks
 
hahaha...well, I guess I didn't check to see if there were any additional fuses back there but will do that. you never know. thanks

Most of your GI problems will be in the lower left corner of your power driver board. Burned connectors, or the fuses right there. Pull fuses and check with a meter.

Before pulling the board for repairs, check the transformer connector for burn too.

LTG :)
 
It's also possible it's a cold solder joint on the GI pins...

I know it's not a WPC game, but I had the two lower GI strings on my DE Hook not work because whoever changed the burnt connector, forgot to solder in the bottom pin... The guy that "Fixed" the game told them it was a transistor that was not available anymore.

Problem 2 was the solenoid that kicked the ball in the drain area over to the right wasn't working. It was a cold solder joint on the PPP board. One of the large diodes was not making it's connection.

-Mike
 
Looks like Q10 is the transistor for that string.

Schematic 3-10 is the diagram for a typical GI string.

Page 132 of the pdf manual.
 
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