Galaga help

[DaveDog]

My original upright Galaga is acting up.  The ship moves to the left on its own(slowly and a little jerky).  It moves left and right just fine when you move the joystick, but when you dont do anything it moves on its own(very annoying in the challenging stages).  The only time it doesnt seem to move is when its giving you your score on the challenge stages.

Contacts on the joystick and 44 connector appear to be OK.  I switched in another board and it worked perfectly, so it looks like its on the board itself.  Anybody know of any chips that I could take a look at, or any suggestions?

[DaveDog]

Anyone??

[Witchboard]

How about cleaning the edge connector of the board that's giving you issues?  Probably won't help, but it's worth a shot.  Are you using a Galaga to JAMMA adapter?

[dabone]

Galaga troubleshooting.




http://www.arcadeshop.com/galaga/galaga.htm


Have you removed and cleaned all of the custom ic's???

I use a small metal brush (Toothbrush size), and do it very gently.


Later,
dabone

[DaveDog]

I cleaned the edge connector when I started to troubleshoot, but no help there.

This is all original parts, no jamma in this game.

I did not try taking all the chips out and cleaning them.

[dabone]

Those custom IC's corrode ALOT..

I work on a galaga for a local pizza place, and get a call on it around once ever 6 months, usually the same thing, random lock up, reboots, etc.

Clean/Reseat the custom chips usually clears everything up for 6 more months or so.


(The sad part is they have 5 games at that location, and the galaga out earns the other 4 put together.)
(The other games are a golden tee golf, ms pac, wrestlefest, Mechanized  Attack.)



Later,
dabone

[SuperGunGuru]

Here's something else you can look into. Randy Fromm has a cool tutorial on troubleshooting input failures. I have a Simpsons PCB that thinks the player 2 coin mech is constantly active. Using Randy's article, I've found the defective IC and now need to find the replacement.

http://slot-tech-ftp.serveftp.com:8080/technical_department/general%20electronics/do%20it%20yourself%20PCB%20repair/do%20it%20yourself%20PCB%20repair.htm

[Stingray]

Those custom IC's corrode ALOT..

I work on a galaga for a local pizza place, and get a call on it around once ever 6 months, usually the same thing, random lock up, reboots, etc.

Clean/Reseat the custom chips usually clears everything up for 6 more months or so.

If you put a thin coating of dielectric grease on the IC legs before you reseated them, wouldn't that help prevent corrosion? Just a thought.

-S

[DaveDog]

Great info guys, Thanks!

I have two galaga boards.