Archive of the former Yahoo!Groups mailing list: MOTM

Yes, the resonance knob on the 490 is "very touchy". Mine started to
self-oscillate at around 3.5 ticks. The manual suggests changing R39
to 51K to 68K. I had both, and went with 51.1K At the high end it
starts to oscillate at a resonance setting of about 4.5. With the frequency
knob in the middle, it starts around 6. It begins to oscillate
around 8.5. at the low end (around 90Hz). Is there any way to get it
to self-oscillate below that?? The 440 goes down to around 20Hz.

Does it sound like a Moog?? While I can't do an AB comparison, it
certainly exhibits the safe goofy response to FM modulation, so I'm
happy :) I don't know if it does the rising cutoff thing
-- it's very hard to tell misusing a 320 as a VCO (the 320 overshoots with
quick CV changes).

Also, in an attempt to minimize gratuitous drift, I pushed the two
transistors together with a bit of heat sink, and cinched them
together with a wire tie. Now if certain people want to call me
names because that's what makes a Moog a Moog, I'll just have to live
with that :)

If I could change the 490 interface, I would have only one input jack
which would leave room for an input level knob. Imho, passive mixers
aren't very useful unless you have a VCA for each input. I haven't
decided if I want to try lowering resistors to increase the input
level.

While I'm on the subject of swapping resistors. Does anyone know a
good way to unsolder MOTM PCB's?? They seem to delaminate very
easily. Just removing R39 removed the foil around both pads. You
don't even want to know about the 700 (I had to use silver to get the
last repair to stick) I've tried using a Paladin solder sucker
(spring-loaded vacuum) and a braid (Chemwick). Any ideas??