A nice one of the early production models with SAD BBD chips.
Roland VP330 Vocoder Plus
I had to take apart all the rocker switches by unsoldering and prying them open and clean the contacts.
Vocoder didn’t work anymore but I found the fault quickly. It were the CMOS switches which act as VCA by fast switching the filtered carrier signal and LP-filtering afterwards.
Vocoder Plus
The Roland people did a very special job here since this is quite an interesting design compared to OTA and optical VCA or FET designs. In terms of costs it must have lowered the production costs by quite some.
Vocoder and string section
String section closeup
I wonder how good this becomes at very high switching frequencies…
