shugart 390 PCB schematic

From: Francesco Messineo <*francesco.messineo_at_gmail.com*> Date: Sat, 8 Dec 2018 20:11:24 +0100 Message-ID: <CAESs-_zMqa6d-cLPpcWsw4qaKe-aLSUgFUzHi0DsTRakjZHPyA@mail.gmail.com> · francesco.messineo_at_gmail.com

Hi all,
one of the drives (0) in my CBM 3040 dual drive suddendly quit working.
Symptoms is always read error 20 (on 18,0). I've quickly checked head
coils and they're ok,
then switched the drive 0 connectors to drive 1 position in the analog
board and the symptom
followed the drive, so the analog board is ok.
I removed drive 0 and it's spindle speed is obviously very wrong
(looks too fast) and I can't get it right with the multiturn pot in
the small PCB on the rear of the drive.
Now, does anyone know where to find the schematic of that little
board? It would speed up the troubleshooting process.
Thanks in advance
Frank