Commodore Magic Voice not working

Commodore Magic Voice came in for repair.

The (speech) audio didn’t work or the speech was mangled.

What I did:

  • Reseated IC’s, didn’t fixed the problem.
  • Measured the clock of the Y1 osc, which should be 640KHz, and it was sometimes 640KHz.. but mostly it was fluctuating.
    So I replaced the C1 & C2 ceramic capacitors, the clock is now stable.
  • Replaced the electrolyte caps.
  • Resoldered oscilator and the 2SC2222 transistor.
  • Reseated the IC’s again just to be sure they are fitted good.

It works!

 

Technical resources

http://www.stefan-uhlmann.de/cbm/MVM/Hardware/index.html
http://www.stefan-uhlmann.de/cbm/MVM/Firmware/index.html

Leave a Reply

Your email address will not be published. Required fields are marked *