So I built the O2 without the 1/4" off board jack to begin with, it sounds pretty good, everything seemed to be in order. Once I got my custom panel from FPE, I set about wiring up the 1/4" jack, it was pretty easy, no problems (so I thought), 4 wires into the PCB connected to the jack, L, R, Gr, and another pin, which I assumed to be Gr as well. Maybe it's some kind of other magic pin?
The PCB has 4 holes, 3 round ones and a square one. I am new to this, but I read that the square one is positive, whatever that means for ground wires, I have no idea. So I put R & L in the appropriate places and hooked up the ground wires how I thought they should go, (mistake), and everything was fine, it sounded great. One small problem...
It clicks or pops when I turn it on now. And even after removing the 1/4" jack and wires the pop remains.
The questions are, what did I do to the amp to make it pop when powering on?
And...
How do I fix it?
Again it did not do this previous to attempting to hook up the 1/4" off board jack.
The PCB has 4 holes, 3 round ones and a square one. I am new to this, but I read that the square one is positive, whatever that means for ground wires, I have no idea. So I put R & L in the appropriate places and hooked up the ground wires how I thought they should go, (mistake), and everything was fine, it sounded great. One small problem...
It clicks or pops when I turn it on now. And even after removing the 1/4" jack and wires the pop remains.
The questions are, what did I do to the amp to make it pop when powering on?
And...
How do I fix it?
Again it did not do this previous to attempting to hook up the 1/4" off board jack.
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I don't recall a square pad being used to identify positive (though it is possible I suppose, with electrolytics for example). A square pad is for Pin 1, as seen at the op amps. At P2, pin 1 and pin 2 are connected together with traces both top and bottom. A 1/4" TRS connector only needs a 3-wire connection. Confirm that the jack is connected correctly, and that the turn-on pop is abnormal.
I figured it out, woooo! I read on a forum somewhere that this sort of problem could be with "transistors upstream of the output stage". So I replaced the voltage comparator and the pop is gone, now to reinstall the 1/4" jack. If I press the button it really fast it just slightly clicks once in awhile. I guess I'll have to order some new opamps, but for the time being it works. Thanks for the reply BTW!
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