Yes, Single supply, one ac secondary connected, as in the ESP schematic, to Ground and AC2.
Or, as in my sketch above, AC1 to first set of diodes, AC2 to ground on the smoothing caps.
Like that, it's been working fine for 2yrs, giving both positve and negative rails.
Or, as in my sketch above, AC1 to first set of diodes, AC2 to ground on the smoothing caps.
Like that, it's been working fine for 2yrs, giving both positve and negative rails.
It appears to be a half wave supply, with the other two diodes unused.
Yes exactly, the power supply was built first and I used a transformer I already had, 2 secondaries, not center tapped, so the power supply half wave, only first set of diodes used.
Seems you have a connection between the adj-pin 1 of your 337 regulator (always 1,25 V above negative output) and your case.
That makes sense, once again stv, my thanks.
And to all, it must be a little bit frustrating as we have here audio engineers, experts, having to deal with novices like myself, trying to explain the problem is in itself difficult. I am very grateful.
I will check everything again with the power supply tomorrow, but have to wait for new opamps to confirm the preamp is working OK.
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