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Problems with certain channels and there gain pots

I have a similar problem in the the gain for channels 6, 9, 12 and 16 all seem to have intermittent faults.
Channel six and nine seem to come back on after a gentle tap on the channel strip, 12 is a lower gain then the rest but is useable and 16 has a problem when you turn the gain pot past 11 o'clock - the level just drops.

Is this an issue that could be repaired?

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I assume you are talking about an audio mixer, here's what i think:

I'm not sure about channels 12 and 16, but channels 6 and 9 seem like having some loose solder contacts, which usually occur with long term use - you need to remove the problematic channel strips and check the solder contacts on any of the pots / switches / connectors that protrude through the top panel - resolder any loose or bad solder contacts (i usually resolder ALL pins on ALL connectors, pots and switches just to be sure).

As for the lower gain on CH12 - see if the mixing slider is connected via wires, if so, compare it to the connections on other channels, see if there is a loose wire or if the wires are connected in a wrong way (i had a "lower gain" issue with a mixer once that turned out to be a wrongly connected mixing slider - i obviously wasn't the first person to repair that mixer...)

Channel 16: check input preamp IC, could be a bad electrolytic filter capacitor or other components, possibly a faulty IC.

Hope some of this helps...


3rq8 (Triarcuate)

Posted on Sep 08, 2009


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