[sdiy] popping a cap into a VCO

[john mahoney]

> without seeing the SCHEMATIC :^) I can't say for sure...

Ain't gonna happen! ;-)

There is a PCB layout in the datasheet, but that's all:
    http://www.synthesizers.com/datasheets.html
The VCO is the Q106, and the cap is shown at the bottom left (the board is
shown upside down, actually).

Funny thing: The datasheet shows a 4700 pF cap but the actual caps say
"10000J" on them. I took that to mean 10000 pF, since the only styrenes I've
seen are the Xicons which max out at 10000 piffs. Not that it matters, in
this case.


> Leakage 'might' be a problem in the larger sizes... if so the oscillator
> will stall at really low frequencies.

Ah. My guess was that the waveshapes might be deformed due to leakage, and
I'll stick with that guess under the assumption that stalling would be the
extreme case.


> Get the best cap you can for the application...

Well, from what I read online (a Field Guide to Capacitors, probably written
by some amateur hack) polypropylene seems to be a good choice in this case.
;-)
--
john