I was building a batch of MOTM-110s tonight and had 1 that had the dreaded noisy pot problem. Trouble was, this pot had never been on a panel! And, it was a new style Spectrol pot that is supposed to be "smoother". With no signal applied, as the GAIN pot was rotated the noise steadily got louder. Well, the culprit was *residue flux under the IC socket*! I took an old toothbrush, dipped it in hot water, and scrubbed along on the top of the pc board on both sides of the socket (my dentist would have been proud!). After it dried, *worked perfect*. Scratchy pot syndrome gone! Just thought you'd like the info. Paul S.
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Noisy MOTM-110
2000-06-21 by Paul Schreiber