Six-Trak repair help needed.

[Grant Richter]

Always start by making sure the patch storage
RAM is happy! By replacing the backup battery
or whatever.

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> From: Hallgeir Helland <hhelland at mailandnews.com>
> To: DIY <synth-diy at mailhost.bpa.nl>
> Subject: Six-Trak repair help needed.
> Date: Wednesday, January 19, 2000 8:03 AM
> 
> 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
> '¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'¨'