Tank Battalion pcb missing parts

[Belike]

I found an original Namco Tank Battalion pcb in one my boxes, I tested it with a Galaxian adapter, for first sight, the game is playable, but the background is white and the colours are dissorted.There are some components missing from the board, the chip at position D2 and the complete heatsink with a 3 legged sound amp(?).Anybody have the similar pcb to identify these chips?

The 2 big 16V 4700mf caps and the 2 "ceramic sticks or something" are also missing, they have any effect on gameplay?
I copied some info from my Galaxian board, but I'm not sure they are 100% identical components.

I guess this pcb was also converted to DC, but in a different way than the Galaxian.

Pic shows this




Any help would be appreciated.

[PaulSwan]

The missing power components are because it's had a DC conversion done to it.
D2 is the one to find. I had one of these at one point but I don't think I have a picture of the board. I'll check though.
Paul.

[Belike]

The missing power components are because it's had a DC conversion done to it.
D2 is the one to find. I had one of these at one point but I don't think I have a picture of the board. I'll check though.
Paul.

Thanks Paul, I learned something new today.

[level42]

Maybe the brightness is simply way up too high ? 

[Laschek]

I have one, but unfortunately this chip has a heat sink glued firmly onto it and I don't want to remove it because I don't want to break the ICs casing (happened before) 
Could it be that its a PROM that contains the bct1-1.l3 Mame file? Color Prom?
http://www.progettoemma.net/gioco.php?game=tankbatt

[Belike]

It has to be that one, the game is 100% playable with sound, only the colors are dissorted.
I found this pic, there is also a heat sink on it.

Thanks for checking.

[Luigi]

Béla, you already noted that D3 is not fixed on the right side?

[Wurstkopp]

Here's a pretty highres pic from mine:

Béla, you already noted that D3 is not fixed on the right side?

That could be the solution..!

[Belike]

Béla, you already noted that D3 is not fixed on the right side?

D3 is originally an empty space on this pcb and also on Niklas's pic.

Here's a pretty highres pic from mine:

Béla, you already noted that D3 is not fixed on the right side?

That could be the solution..!

Thanks for the pic, seems like the heatsink was removed from your chip, can you read what is written on it?

[Wurstkopp]

Sorry, it's the only pic I have, the cab is in the museum now. Maybe Punkrockcaveman can have a look at it when he gets there next time.

I think Luigi meant the diode on D3, it's loose on yours. Also there are other diodes (D1 + D2) missing...

[Belike]

Here is a closer pic from that area, can't see the difference

There is also a broken cased 74ls74 chip on D5, but I think it has not too much sense to replace it, if I don't find that prom in d2.

[Laschek]

Take a look below the white cable at the edge connector, there is Diode 3/D3 which is connected only on one side.
My guess is that it belongs to the AC->DC circuitry which is shut down on your board. Thats why D1 and D2 are missing, too.

[Belike]

Ah ok, I thought you mean "D2" is the chip in position D2, not the diode.
Took another pic from my beloved photo modell
Those 2 diodes are disconnected on 1 side, I thought it is ok like that because of the AC/DC conversion, isn't it?

I think the AC/DC conversion has to be ok, otherwise the pcb wouldn't be playable.

[Etienne MacGyver]

Yep, those diodes do the the AC to DC conversion normally on the board, but your board is modified to use DC from the connector, so i guess they are cut for that reason

also you can see the jumper wire to the point where the diode connection was.

[Belike]

A guy on klov helped me, it was a 2125 ram.
Graphics is fine now, just have a little issue with the tank engine sound.