Hello, I have a 500.1 rev 11 amplifier, which arrived with a damaged output stage and the mic4427, 1 240 ohm resistor, 1 75 ohm resistor and the 4 irf540 fets were replaced, but now the low ohm led turns on and I notice that it is not I have power on the mic, I only see 1.3v, any advice to know why the yellow led was understood. Regards
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If you pulse the remote on then immediately off, do you see the supply voltage on the 4427? You have about 15 seconds to check the 4427 voltage after removing the remote voltage.
It sounds like the low-voltage supply is inoperative. Do you have 5v output on the 5v regulator near the low-voltage transformer?
Do you see pulses (swinging from ground to 2x B+) on the drain of the FET that drives the low-voltage transformer?
there is no trace of pulses, I have checked the 4 diodes and 1 was open, I changed it even so there are no pulses
Is the 0.1 ohm resistor connected to the source leg of the FET that drives the low-voltage transformer (Q612) within tolerance?
Set? Install?
You can but I'd check the signal on the gates of the outputs before installing them.
You can but I'd check the signal on the gates of the outputs before installing them.
now I already have a pulse on the fet that drives the low voltage transformer, but I don't have a pulse on the mic4427 inputs
there aren't any, I see 4 transistors under the board that seem to be heating up I see some smoke, I'll take them out and check
hello, good morning, I already checked them and 1 came out in bad condition, I decided to put them all new, I still have no pulses and the low ohm led does not turn off
