Mr. Buchla was (still is, really...)a real hot-rodder. He used the
best parts, techniques and ideas of that period. The 60's surplus
scene in California was a bonanza due to the war and the economy.
These same ingredients fueled the Fender plant in the 50's.
Good engineering is important, but there comes a time when you just
have to push something until it get hot and starts to crackle. When
in doubt-BORE IT OUT!!!
I LOVE electricity...
Chub-hot rod engineer with the facial scars to prove it!
--- In motm@yahoogroups.com, "Paul Schreiber" <synth1@a...> wrote:
> (yawn, I've been messing with this thing for 6 hours, and I have to
get up at 6AM)
>
> Overall, the mechanical construction/pcb/component selection is
better than a Moog from the same
> period. Don was/is an aerospace engineer by trade, so all the IC's
are military surplus
> (ceramic/metal cans). There are a few LM741s in sockets (selected!)
but most are old Teradyne
> LM341H, which was a LM741 in a can with better temp. performance.
There are also a few Motorola
> MC1456CGs (can), and the later modules (1977) use RC4156 quad op
amps or a Fairchild uA749 dual.
> Most modules appear to be made in mid-1974.
>
> What is really disappointing is Don used the same Moog 'trick' of
using the front panel as a
> ground. This was to "save labor" but really all it does is make for
a noisy system. There is
> already lots and lots of point-to-point panel wiring, why adding 1
buss wire and a solid ground
> caused concern is beyond me.
>
> I fired up the 294 Comb Filter. This, and the 10-ch 295, are really
like the Moogs: low pass,
> bandpasses, and a high-pass all in parallel. I'll run AP plots
tomorrow, and compare it to the
> Moog and the MOTM-450 :)
>
> A handful of TL071s, new jacks and grounding should fix the old gal
right up! Slide pots are
> pretty icky, though. The rotary pots used are sealed CTS, not shabby.
>
> Double sided pcbs, no solder mask, no silkscreen. Not much
bypassing, if any.
>
> Paul S.