I hope this information will help someone. I’ve included some pictures of my notes. Things I learned after fixing 7 s&T boards (2xfathom, embryon, 4x 8bD)in a few days. Number 1, don’t wast your time until you have replaced all caps. The bad caps effect the voltage and makes the chips seem bad. I waisted a lot of time removing chips and sockets. I did not find one bad socket. Number 2, the trimmer pots were almost all bad. You can remove and solder the 2 contacts together temporarily. I did this on all boards with no sound. Number 3, you need to have the correct jumper settings. You can look at my boards for these 3 games. Beyond that there was a few rare nightmare issues. C47 and c48 had the wrong part installed causing major buzz. The key here is to look for replaced parts and inspect closely. Another problem was a week contact that needed to be soldered better. FYI, Touching the board in the middle area causes a buzz to prove you have sound to the speaker. I personally would not attempt this without a desoldering iron and a voltmeter. Thanks to Fytr and Quench for fast reply on my questions. Thanks, Del
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