[sdiy] EFM VCF6

[Tom Arnold]

On Thu, Mar 31, 2005 at 10:24:29PM -0800, harrybissell wrote:
> I'd try to match the diodes. You could measure forward voltage at maybe
> 200uA or so... or just use the diode scale on some meters.  You have to match
> in horizontal pairs only.

I took a bag of 1000 1N914's ( cause I had them ) and found out of that 2
sets of a dozen that were closely matched.  I do this sorta stuff while
watching really really bad movies on TV ( in this case it was Too Fast Too
Furious ).

> The resonance feedback blocking cap (C9 in my schematic) needs to be
> MUCH larger... like 100uF to get full resonance down to low frequencies.

Yeah. Saw that note in the EFM archives.  I'll build it stock first and then
tweak.  Also assembling a VCO8 and VCO12 purchased during last years big
board blowout.  I've heard you rave about the VCO6 so I'm building it
first... :-)

Its been hard to find a non-mylar cap that was physically small enough to
fit the board.  The ones from Mouser are just barely the perfect size as far
as width, thickness, and lead spacing.  Only 5% tho.

-- 
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 - Tom Arnold -       When I was small, I was in love,                  - 
 - Sysabend   -       In love with everything.                          -
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