Repaired: Galaga

channelmanic

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Donor 3 years: 2011-2013
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Thought I'd share an odd Galaga repair with y'all since it's not on the 2 main Galaga troubleshooting web pages...

Symptom: Player and enemy graphics are tilted 45 degrees. Player explosions are divided into 4 pieces. Enemy explosions are represented by the number 20 over the number 31. If the enemy is tilted left the numbers are upside down. If the enemy is tilted to the right the numbers are right side up.

Solution: Replace bad 74LS153 at location 1B on the video board.

The inputs were good but the outputs were stuck low with very narrow racing pulses. The outputs of this chip drive pins 1 and 2 of the graphics ROMs.

Enjoy!
 
I just got my Galaga machine running today as well.

Symptom: Machine freezes at boot, screen filled with M's (or W's)...

Solution: Made adapter for Gallag bootleg boards... tada.

Seriously, I've been tinkering with this friggin' Galaga set for months... I have some replacement RAM here, just got them yesterday. But I really don't feel like screwing with it anymore...

Glad you got yours fixed and going right, one of these days I'll get mine back up and running properly.
 
I got so sick and tired of flaky damn Galaga boards that I built a "renew kit" for them... all new 24, 28, 40, and 42 pin dual wipe sockets along with all new resistor packs.

Those cheap assed sockets and horrible resistor pack problems will drive you INSANE until you just replace them all. Once you get all those done and the chip legs cleaned then you can start with a stable board that you can finally troubleshoot.

Oh, and those TI sockets used on those boards? The white sockets make contact on the inside and outside of the legs. The black sockets are of 2 different types. One is a single wipe that only makes contact with the inside of the chip legs and the other is a dual wipe that makes contact with the SIDES of the legs.

Those sockets suck... and nobody cleans the skinny sides of the legs.
 
I got so sick and tired of flaky damn Galaga boards that I built a "renew kit" for them... all new 24, 28, 40, and 42 pin dual wipe sockets along with all new resistor packs.

Those cheap assed sockets and horrible resistor pack problems will drive you INSANE until you just replace them all. Once you get all those done and the chip legs cleaned then you can start with a stable board that you can finally troubleshoot.

Oh, and those TI sockets used on those boards? The white sockets make contact on the inside and outside of the legs. The black sockets are of 2 different types. One is a single wipe that only makes contact with the inside of the chip legs and the other is a dual wipe that makes contact with the SIDES of the legs.

Those sockets suck... and nobody cleans the skinny sides of the legs.

Yeah, I already replaced all the sockets on the board, checked all the chips, cleaned them all, verified the EPROMs, replaced any customs that I needed to, checked the cable, etc etc etc... my final shot before I send it out is going to be replace'ng all the RAM. I seriously doubt it's the ram, but you know what... screw it. I've already replaced everything else on the board, might as well do the RAM while I'm at it. If it fixes anything yay... if not, oh well.

I hate this board, it was working when I picked it up... moved it... stopped working... so that's why I doubt it's the ram, but I want to be able to say I tried everything before I send it to someone else.

The cabinet just set in the room for months, I had to get something in it... when I came across 2 Gallag boards for $20.. wasn't going to pass that up. One of them worked with an adapter, so now atleast there's colors and stuff moving on the screen. The sounds and starfield is off a little from a real galaga, but screw it... better than nothing.
 
I hate those sockets that contact the sides of the legs. Yeah the chips are easy to put in but they barely hold them in. Another problem with galaga boards is they should have put a support in the middle of the board. Cheap sockets, resistor packs, crappy custom chips, just an overall cheap design.
I fixed two galagas yesterday that I had been putting off forever. Simple fix on these, cleaned the customs and a few new roms/sockets.
 
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