Prophet VS: Bad CEM?
Posted: Wed Aug 03, 2011 12:30 am
Hi All,
Curious if anyone has experienced a similar problem with their VS:
The joystick works, but doesn't alter the waveform mix. It goes through the ADC okay because I can see the vector changes on the screen, but the joystick has no effect on the sound any which way you try it.
I'm guessing this could be something in the de-multiplexing. . . perhaps a $400 bad CEM5530, or a $.25 4051. It looks like they put one 5530 right over the hot PSU
and it sends 30 of the 32 voltage controls that I think set the waveform mix into 8 voices. I'm probably not going to get too deep until I get the service manual, but any advice is appreciated. It's a rack version that has a sorted past, all the patches were programmed inaudible when I received it, and it's been totally brainwashed.
Thanks!
Curious if anyone has experienced a similar problem with their VS:
The joystick works, but doesn't alter the waveform mix. It goes through the ADC okay because I can see the vector changes on the screen, but the joystick has no effect on the sound any which way you try it.
I'm guessing this could be something in the de-multiplexing. . . perhaps a $400 bad CEM5530, or a $.25 4051. It looks like they put one 5530 right over the hot PSU
and it sends 30 of the 32 voltage controls that I think set the waveform mix into 8 voices. I'm probably not going to get too deep until I get the service manual, but any advice is appreciated. It's a rack version that has a sorted past, all the patches were programmed inaudible when I received it, and it's been totally brainwashed. Thanks!