With the black probe on the negative rail. what's the DC voltage on pin 2 of the 21844?
If you drive a signal into the amp, do you see that signal on the output terminals of the TL072 and the Lm211 on the driver board?
If you drive a signal into the amp, do you see that signal on the output terminals of the TL072 and the Lm211 on the driver board?
I changed the tl072 other guy told me i should change that and there is output on the 072 and there is output on the lm211
I resoldered the inductor last night and had audio then i took the remote off and applied it again then no audio output. Then replaced the inductor with the exact same inductor from a donor board then it worked again and now its again no output audio
All voltages are present going into the driver card and i have replace the card also with a known working card still the same issue
Did you check the muting transistor for leakage?
As a side note, it's bad practice to resolder large areas of the board. Bad connections typically have a layer of oxide that may not fully float to the surface. This will leave a connection that's marginal at best and likely to fail again. It's better to troubleshoot to find the fault and if it's a bad connection, then you properly repair that one connection.
As a side note, it's bad practice to resolder large areas of the board. Bad connections typically have a layer of oxide that may not fully float to the surface. This will leave a connection that's marginal at best and likely to fail again. It's better to troubleshoot to find the fault and if it's a bad connection, then you properly repair that one connection.
Some amps seem to be sensitive to not having a mute delay (they will blow the output FETs).
Repeatedly power up the amp (muting transistor in the circuit) and measure the DC voltage on pin 2. Does the voltage remain relatively constant when it has audio and when there is no audio? Or does the voltage vary widely?
Repeatedly power up the amp (muting transistor in the circuit) and measure the DC voltage on pin 2. Does the voltage remain relatively constant when it has audio and when there is no audio? Or does the voltage vary widely?