[sdiy] Fun with the Oberheim M6

[WeAreAs1 at aol.com]

At 12:28 PM 8/25/04 , Tim Parkhurst wrote:

<<  >I was running the calibration routines after every chip swap and I did
>notice that the problem was getting slightly better (still noticeable, but
>not as bad). Well, on a lark I decided to run the calibration three or four
>times and THAT CURED THE PROBLEM! John M and I both thought that maybe the
>VCFs were out of 'tune' far enough that they couldn't be brought back by a
>single recalibration, and that the internal processor was able to bring them
>back a little closer each time (each run building on the results of the
>previous).
>
>Has anybody had this sort of thing happen? Perhaps it’s a lesson for all of
>us using micro-driven analog equipment. >>

Hmmm.  15-20 year old synth + IC's in sockets + Oxygen (or what's left of it 
these days) = Oxidation on chip pins and socket pins.

Take those CEM chips out of their sockets and clean the pins with an Xacto 
knife.  If there are any 4051's and TLO84's or TLO82's in sockets (especially 
ones that are part of the CV demux circuits -- they'd probably be next to the 
4051's), take them out and clean them too.  Work the chips in and out of the 
sockets a few times to help clean the socket pins.  Use a drop or two of Cramolin 
to help break up the oxide buildup.  Wear an anti-static wrist strap while 
you do this.

Michael Bacich