Casio VL-Tone Circuit Mystery (is this an error in the envelope detector schematic?)

David Hilowitz's video on the Casio VL-Tone: https://youtu.be/3TT5nAW8gi4
SyntherJack Casio VL-1 secrets: https://syntherjack.net/casio-vl-1-secrets

Support this channel via a special purpose donation to the Georgia Tech Foundation (GTF210000920), earmarked for my work: https://youtu.be/VBu-LST1p9c

Видео Casio VL-Tone Circuit Mystery (is this an error in the envelope detector schematic?) канала Lantertronics - Aaron Lanterman