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MOTM

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Message

MOTM-120

2005-05-18 by Tom Adam

I was surfing the net a bit and stumbled over this link:
http://www.techman.synth.net/techman_website2_00002e.htm
copy:
"When it came to testing this module, I was a little perturbed that it 
didn't work as I expected. in sub mode, turning up each of the four sub 
octave pots produced glitches in the audio if I had signal on both the A 
IN and B IN jacks. This couldn't be right. ... This time I happened to 
put the scope probe on the non-inverting input of the input comparator, 
and lo, the glitching stopped. Aha.. the capacitance of the scope probe 
had stopped the clock jitter. Solution: I happened to have a couple of 
18pF ceramic caps handy, so I put these across the non-inverting input 
and ground (Pins 2 & 1) of both of the 311 comparators. Problem solved. 
The module now appears to work as intended...."

Since I was experiencing the same problem, I tried it out.  I needed to 
take apart the whole module to be able to fit the caps, but the result 
is very nice. Now I know what a MOTM-120 should sound like. Very cool!

Cheers,
Tom

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