Galaga Ram Issues?

WarLordAG

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My Galaga started acting up a while ago. I took the board out and started to take the chips out. The chip legs had a ton of black stuff on them that didn't come off just by scrubbing with a tooth brush. I started to sand one, and while it did work, it took a leg off the chip. Below I have a picture of the chip in question. Almost all the black chips like these on the board of the black stuff on the legs.

When I turn Galaga on, I get the screen below that is upside down. If I turn it off and on repeatedly I'll get it right side up with the occasional message below it like Ram 1H or Ram 4L.

CIMG2225.jpg


CIMG2227.jpg
 
I've sanded their legs and cleaned the chip and socket.

I even just did it again for the hell of it, and it's still giving me the errors.
 
The problem with Galaga is a combination of crappy sockets and tarnishing legs. Add in crappy resistor packs and you end up with a board that is VERY finicky after years of use.

Clean the legs on the customs on the video board (7xx, 4xx, and the one next to them) before you pronounce the RAM bad.

Any customs that have legs falling off can be repaired by soldering on legs from a donor chip. I keep a few bad EPROMs around just for legs. ;)

RJ
 
The chip you have pictured isn't a RAM, it's one of the custom chips that populate the board. They are available from other boards, and a few have been reproduced.

If you do source them from other boards, you'll find the legs in better shape since there doesn't seem to be a dissimilar metal issue on other Namco boards besides Galaga.

The first two numbers are the chip type, the second two digits can be ignored so they're represented as xx. Here's a helpful guide to aid in your search:

http://www.multigame.com/NAMCO.html
 
Thanks

I have the machine running right now after power cycling it 3 or 4 times quickly.

Could this possibly be a power issue since I went over the chips already? I thought I had heard that Galaga was a good candidate for a switcher upgrade.
 
The consensus is that Galaga is very picky about 5v and it's not an absolute value between machines, some like 5.01 and others only boot at 5.30.

Measure across the axial cap on the board that is near the edge to get a more accurate reading than just measuring at the switcher terminals. It might take some experimenting to find the voltage where it boots the first time, every time.

Here's some other helpful Galaga troubleshooting info:
http://www.arcadeshop.com/galaga/galaga.htm
 
The consensus is that Galaga is very picky about 5v and it's not an absolute value between machines, some like 5.01 and others only boot at 5.30.

No, the consensus is that namco used really crappy sockets, and if you don't replace them all, you board won't be reliable.

Jacking up the voltage to 'compensate' for poor socket connections is just stupid.
 
No, the consensus is that namco used really crappy sockets, and if you don't replace them all, you board won't be reliable

Agreed.

They also used some crappy flat resistor packs that cause lots of intermittent problems too.
 
Does anyone on here swap out galaga boards? My semi working board and some cash towards a known repaired and good to go board?

I know there are a couple games guys will do this with.

I'd rather not hunt down these custom chips and put in new sockets if I can do the above.
 
I've sanded their legs and cleaned the chip and socket.

I even just did it again for the hell of it, and it's still giving me the errors.


Don't sand the legs of expensive and hard to buy IC's! This destroys what little finish is left on the IC pins, can potentially weaken the leg if sanded enough and can expose them to high static voltages depending on what you use to sand them.
To clean them - use Tarnex and rinse. Takes about 15 seconds and is far more thorough and easier on the IC.

IC sockets - replace them. "Cleaning" them just postpones the inevitable.

Ed
 
Most namco customs have sliver legs... so you get that nice black silver-oxide coating... try tarn-x or a similar silver cleaner to remove the oxidation with as little damage as possible.

I think the root of the problem on these customs was the silver plating process used. Same goes for just about every TI chip of that era. The problem is the chemicals used in silver plating eats away the steel pin under the silver plate. This is why the pins break off when you look at them. The best bet is to clean them with the most gentile method possible that gets the job done. If most of the silver plating is still there you can use tarnX or something similar. If the silver plate has flaked off I find that a fiberglass scratch brush works great to remove the rust.
You will not have a reliable galaga board until all the sockets have been replaced, customs cleaned and resistor SIPS inspected/replaced. If it has the flat style resistor packs its best to yank them and replace them all. Also a visual inspection of these is usually not good enough. Most times a bad one will look ok and test bad.
Once you have reworked a galaga board you will understand why people have to charge over 100 bucks for it....alot of time involved.
 
I'm going to order the switcher kit, and go from there.
I really feel like I'm having a power issue as well, and if not, the switcher was already on my list for this game anyway.
 
I won't have any shopped boards until mid to late July. Too much business travel going on.
 
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