Six-Trak repair help needed.

[Hallgeir Helland]

Hi,

I'm having a hard time locating the fault in a Sequential Six-Trak.

It outputs very little sound, and the notes (you can barely
hear them) are all the same: low rumbling. The control parameters
seem to be screwed up somehow - the envelopes for example behave
rather strange, like backwards. (software envelopes) I measured the
CVs into the CEM 3394 chips and they are mostly too low; for 
example the VCA CV is max 1.6V (should be 4V). The pots on the
front panel behave erratic, too: the "value" pot seemingly jumps
back and forth between values and won't go down to zero.

I suspected the MUX associated with the DAC but replacing didn't
improve the situation. The DAC btw outputs what I'd excpect it
to. (but those strange envelopes appear there, too.)

I tried swapping some key op-amps, too. Didn't work.

I am thankful for any help.

Hallgeir

-- 
.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.
 Hallgeir Helland   hhelland at mailandnews.com     
    Evlogia           http://fly.to/evlogia
'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'