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MadMikeAU
5th July 2006, 03:23 PM
OK. I have finnaly got around to looking at this.

Made a new harness. Adjust the voltage to correct levels as per manual. No change.

Started lloking at the graphics daughter board. Without this in, the graphics look good, but no sprites. Fixed up a couple minor things. Got it play good, and then back to the glitches. I have also now lost sound :cry

I have started a log on my site under "projects". (http://www.gameinfoonline.com)

Any input is apreciated

MadMikeAU
6th July 2006, 10:42 PM
Anyone got a schematic for this mofo?

Arcade King
7th July 2006, 06:10 AM
I had a look through my crap and the schematics are not in the manual :(

MadMikeAU
7th July 2006, 08:43 AM
Exactly. Anyways, replacing those 2 caps got rid of 99% of the glitching. I think the other 1% is caused by crud in the sprite board sockets, as wiggling it makes it go away. I blew air into the sockets and it was glitch free for about 5 minutes.

As for the sound: the 12V wire on the harness came loose.

So, I think this one is saved from the tip :D

MadMikeAU
8th July 2006, 10:50 PM
Just to follow up...
I did resolder the 12V and that brought sound back.
I got some contact cleaner spray and sprayed in the sockets for the sprite board. Now the game is 100% Not bad for a 25 year old PCB. In fact one of the chips is marked as 1977 !!! Thats the best part of 30 years old.

Only problem with that spray is that now I have created a clean patch and you can see the grime(or at least dust) of ages.

wyldcat34
14th November 2017, 02:55 PM
I'm reviving a totally dead thread here, but I just got one of these boards. It works with sound, but the colour is dark and wrong IE - the chopper is black. Any ideas where to start? Cheers!

Womble
14th November 2017, 03:55 PM
A couple of options, post a good high res photo of the board if you can.

If I had to place a bet blind, I'd start sniffing around the video DAC, probably a resistor network or three.