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Cooljerk

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I've had this board for several years now and it worked fine, but the last time I pulled it out to give it a run, I noticed all the BGM was missing. The sound effects still play, but I get no BGM anywhere. The rest of the game runs like normal.

I'm not very well versed in diagnosing PCB problems like this, if I were to try and fix such a problem, what kind of literature should I look into? Any general tips about how I could diagnose my problem?
 

ic3b4ll

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Hmmm... It's best if you ask. In this case it's likely either the YM2151 (?) died or you have an issue with the analogue section of the sound system. I'll take a look at one of my boards and try to give some advice.
 

ic3b4ll

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If you have no experience doing repairs you are better off not doing anything. It's not a good board to start with and it's likely you'll do more harm than good.

Just friendly advice, ok?

If you are comfortable desoldering chips and replacing capacitors then read on...

Ok, checked a board and it has 2 FM synth chips. It's strange that both died suddenly so the problem should be elsewhere.
I'd start by replacing the Z80 CPU. It should be socketed so it's easy to try that. Swap it and check if the problem goes away.
The fact that you have sound effects make me suspect something else however. I think in these boards the analogue sound section works as a mixer, so it's likely you could have an issue with an op amp or surrounding passives.
Doing a recap could be a possible solution to your issue and failing that, replacing the op amps.
Without actually looking at the board and doing some probing it's all the advice I can give right now.

Good luck!
 
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