Midway Galaga - broken capacitors, dip issues

hindered

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I've got a Galaga pcb that I brought back from dead. Seems to work 100% besides some dip switch flakiness and some broken caps. The 104 I5Z caps are .1uf 50v caps right? Can I replace them with 103 ceramic caps? If not I'll add some to my next mouser order.

Dip switch flakiness - if all switches are off, the game works. But if I set the game for 3 ships, it reboots after ram ok message. I verified the roms are good and metered the switches. Next suspect are the 74ls157s? And the resistor packs I guess.
 
I've got a Galaga pcb that I brought back from dead. Seems to work 100% besides some dip switch flakiness and some broken caps. The 104 I5Z caps are .1uf 50v caps right? Can I replace them with 103 ceramic caps? If not I'll add some to my next mouser order.

Dip switch flakiness - if all switches are off, the game works. But if I set the game for 3 ships, it reboots after ram ok message. I verified the roms are good and metered the switches. Next suspect are the 74ls157s? And the resistor packs I guess.

Yeah, there's a board version that if you set DIP 5 on one of the banks it goes into a reboot loop. It's a real pain in the ass.

RJ
 
Yeah, there's a board version that if you set DIP 5 on one of the banks it goes into a reboot loop. It's a real pain in the ass.

RJ

Yeah that's what I ran into, I had my dip banks switched so no wonder all the settings were wrong. Once I realized my mistake everything is good.

I replaced the four caps and the board is running well now. No need to replace the resistor packs or sockets at this point, that's more effort than I'm going to put into a working board I plan to sell sooner than later.
 
Yeah that's what I ran into, I had my dip banks switched so no wonder all the settings were wrong. Once I realized my mistake everything is good.

I replaced the four caps and the board is running well now. No need to replace the resistor packs or sockets at this point, that's more effort than I'm going to put into a working board I plan to sell sooner than later.

Glad you got it working. These boards can be a PITA and I don't charge enough when I work on them for all the hours it takes to rebuild them.

On the other hand, ones I've rebuilt sell for a premium. :)
 
I charge $100 plus shipping and plus extra if I have to replace multiple customs or fix someone else's attempted repair.
 
Glad you got it working. These boards can be a PITA and I don't charge enough when I work on them for all the hours it takes to rebuild them. :)

But what about that great sense of accomplishment you get after changing all the sockets, replacing all the resistor packs, the LS107 in the clock chain ( was there a bad batch of these back in the 80s ? ), the one or two bad 2147's, soldering half a dozen legs back onto customs ( if you're lucky)... then finally it boots and no long crashes at just the slightest flexing, moving or breathing on the PCB ;)
 
But what about that great sense of accomplishment you get after changing all the sockets, replacing all the resistor packs, the LS107 in the clock chain ( was there a bad batch of these back in the 80s ? ), the one or two bad 2147's, soldering half a dozen legs back onto customs ( if you're lucky)... then finally it boots and no long crashes at just the slightest flexing, moving or breathing on the PCB ;)

Call me crazy, but I take these and lift them up about an inch off the bench and bounce the shit out of them repeatedly. I consider the repair a success when it doesn't reboot while doing that. :)
 
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