MOTM

In the SUB mode it should not matter what is going to input B at all.  
The B input should be ignored.  Why would eliminating "clock jitter" on 
the B input make any difference?  It seems to me this has little to do 
with what mode the 120 is in, because in the scenario described there 
are inputs on both A and B, and the solution is to modify both comparators.

Paul, what is your take on this modification?

-Richard Brewster

Tom Adam wrote:

>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
>
>
>  
>