the problem is the last op-amp. i have tryed with NJM4560, OP275, OPA2604, MC1458, the best solution for this application is NJM4560. the right channel pop is cleared, is still remain very little pop on the left channel..
i'm still thinking, but if i change the schematic? i mean, if i change drain muting fet from op-amp input to op-amp output?
i'm still thinking, but if i change the schematic? i mean, if i change drain muting fet from op-amp input to op-amp output?
Orion 250sx ps fets or bjt
I made an error and replaced D44 bjts with IrFZ44h fets in the ps. Never seen D44 before and so that’s why I made the mistake by moving to Z. There are no gate resistors in this amp. Pull downs are 33ohm resistors.
Also found 1 rectifier shorted so replaced both with 1620x parts.
The amp powers and is functional with less than 1A current draw at idle. No load tests yet. The z44 fets don’t get warm at all. Nice steady equal square wave at their gates. No regulation pwm from what I can tell. Do these amps use PAM? That wouldnt work I don’t think for fets.
Have fets been tested before in these amps?
I made an error and replaced D44 bjts with IrFZ44h fets in the ps. Never seen D44 before and so that’s why I made the mistake by moving to Z. There are no gate resistors in this amp. Pull downs are 33ohm resistors.
Also found 1 rectifier shorted so replaced both with 1620x parts.
The amp powers and is functional with less than 1A current draw at idle. No load tests yet. The z44 fets don’t get warm at all. Nice steady equal square wave at their gates. No regulation pwm from what I can tell. Do these amps use PAM? That wouldnt work I don’t think for fets.
Have fets been tested before in these amps?
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