Galaga PCB - Could someone get me a picture (close-up of CPU section)?

[RetroACTIVE]

OK... I've restored a Galaga (Midway) board set... I am very excited that it works... but here is what I noticed...

Before I cleaned it up the CPU board had 2 Z80A's... in locations 4E and 4J respectively... and 1 Z80 in location 4M... When I repopulated the board I replaced the Z8's correctly according to the schematic... 2 Z80's (4E and 4J) and 1 Z80A (4M)... and it did not work!  I had to put it back the other way... which is reverse from the documentation

Has anyone else seen this?

Thanks

[ChadTower]

Small discrepancies in documentation for arcade games in common.

Are you sure all of the chips involved fully work?  And sometimes you'll see in old boards people have altered them a bit to get around design flaws or to accommodate the parts they had on hand when it went down.

[RetroACTIVE]

Small discrepancies in documentation for arcade games in common.

Are you sure all of the chips involved fully work?  And sometimes you'll see in old boards people have altered them a bit to get around design flaws or to accommodate the parts they had on hand when it went down.

.

The board has virtually no re-work... there is 1 wire and a cap across two legs of another IC... I don't recall where right now... but that could be what you are referring to.  I have two sets of Galaga boards... both are exactly the same (in terms of the rework)... so I figured it was "factory".  As far as fully working... I'm pretty sure they do... the game works flawlessly and they are pretty significant parts so if they were faulty... it would be easy to tell.

Thanks for your input... I think I'm going to investigate the rework some more... maybe it is contributing to it.

[ChadTower]

I've seen a couple of instances where the factory did a little rework, too, but don't change the rev number on the board or anything that would indicate your schematic is a little out of sync.

[RetroACTIVE]

Thanks Chad... I double checked the re-work against the schematic... it is correct according to the documentation... so I think it was factory.

I'm going to ask anyone who has a working boardset to post a pic of the cpu section if they would'nt mind.. this is bugging me... It could very well be the type of Z80A I have... there are several different incarnations... if I could get a pic of someone who has a working board... I could check it against mine...

Thanks

[ChadTower]

Maybe...

[RetroACTIVE]

Maybe...

Yup... I've pretty much lived at that site for the past year... Unfortunately I want a closer pic... I'd like to see the IC markings on each of the CPUs if possible....

Once I get all this sorted out... I'm going to build my second cabinet... it will be a Galaga replica... I have an old original Galaga cabinet (its in poopy shape) but it is just fine to use as a giant stencil... then when I'm done I'm going to give it to the first BYOAC member who wants it... It could be resotred for those with that sort of desire (because I don't intend on dismantling or destroying it to copy it)... but I would rather build a new replica...

[ChadTower]

I have a Star Wars in that same boat.  Water damage.  Looks good and has good art but you could probably kick it to pieces.  The back flaked apart in my hands.

[fredster]

You should try that request on the RGVAC.  I bet you'll have an answer in minutes.

[RetroACTIVE]

You should try that request on the RGVAC.  I bet you'll have an answer in minutes.

Done...I took your advice... we'll see what it yields.

Thanks

[Raven..]

I have several Galaga boards.  I replaced all three chips with Z80Cs.  They work great!

[RetroACTIVE]

I have several Galaga boards.  I replaced all three chips with Z80Cs.  They work great!

A gentleman from RGVAC stated he had same success with Z80Bs as well... I will end up going this route as well.  Thanks