2 layers99.1 × 86.4 mm

Opl3 sound
lgugelmann/HD6301_thing
I recently received a few samples of a Hitachi HD6301V1 in a DIP-40 package. It's a 1MHz 8bit CPU derived from the Motorola 6801 with a few extra instructions.
58 parts3MIT
Boards in 1 GitHub repository, designed in KiCad, that use the LM4818MX by Texas Instruments (-40℃~+85℃ 1% 1-Channel 1.5mA 2V~5.5V 350mWx1@16Ω Automatic mute/no-noise switch、Enable/shutdown function、ESD protection SOIC-8 Audio Amplifiers ROHS). See how each wires it, with its parts, size, README and files; the LM4818MX’s symbol, footprint and pinout are on its own page.

lgugelmann/HD6301_thing
I recently received a few samples of a Hitachi HD6301V1 in a DIP-40 package. It's a 1MHz 8bit CPU derived from the Motorola 6801 with a few extra instructions.