Archive of the former Yahoo!Groups mailing list: MOTM

(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.