A Moogle  🏳️‍🌈 💻 🎮 🎶 🇸🇪

Thread about the fun stuff I've had to debug over the past week and a half, working on modeling netlists of arcade sound circuits!

1) A BJT intentionally being railed to +15V to force it into reverse junction breakdown, to use it as a white-noise source with a minimal number of parts. Had to HLE it using a uniform-spread white noise input node.

2) On a different board, a pair of XOR gates, with one as an inverter, looped back on each other, to form a cheap clock source for a CD4006 shift register, also looped back on itself to ostensibly form an LFSR. Had to replace the XOR-gate clock with a proper clock source.

3) An Atari schematic that listed a resistor value as 330-ohm in the Bill of Materials (BOM), but 330K-ohm on the schematic. The BOM was wrong. Using a 330-ohm resistor turns the intended band-pass filter into a brick-wall all-stop. Not terribly useful.