Circuit Overview:
This is an FM synthesis machine w/2 identical looking voice boards. I assume with vlsi chips etc. 18 or 9 voice depending on stacking of 'oscillators' at 1 or 2 per voice. 2 - 4 op FM synthesis.
Service Tips:
Only one i've seen from synthark had 2 fuses in AC feed to + -12V supply blown. .2A or so..make sure to use T500mA. Seemed fine, Then glitchy startups frequent w/ no boot or dig. noise accompanying certain sounds..Doug wants to just deal w/ it for now. Maybe a reset timer is off. When it's not making weird noises or just making no tones, I see putting some sounds like steel drum on DCG2 is very low volume...fine on DCG1.
Parts:
A lot of discrete parts so let me know if you need something.
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