If you look at it as a (high impedance) conductor loop then it´s clear that it will pick up magnetic field. Check your layout so that the area inside the loop is as small as possible. That will lower the induced voltage according to the law of inductivity Uind.=dPhi/dt= d(B*A)/dtGood Morning everybody. I am working on revision boards of the units and still try to cure everything that I notice. I invented that small circuit to for the rectified side chain signal. Its super simple and uses a voltage divider R3 / R4 to change the ratio. It works super and as intend.
BUT - in the middle postions when R3 ≈ R4 a 50Hz noise in the audio signal increases by 6dB. (side note: its always R3 + R4 = 1Meg)
The Values of R1, R2, R3, and R4 are all changed by switches.
Does anyone has an idea on this?
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Has anyone an idea for a power transformer that could deliver 120mA @ 225 - 250V and 4A @ 12V ?
I don't like the way the +68V is generated from the +250 - a transistor fail might be catastrophic (depending on what it's used for)