Ok after looking over the circuit for a bit I was able to trace both pins 13 and 15 back to the same points. They lead down to the main board via a pin (Vgs). After which the trace leads to a bank of 4 transistors right beside the power supply FETs.
The trace seems to connect to the center leg of 2 of the transistors (C1027). I assume these are the driver transistors?
Could these have failed and need to be replaced?
Thanks
The trace seems to connect to the center leg of 2 of the transistors (C1027). I assume these are the driver transistors?
Could these have failed and need to be replaced?
Thanks
Ok I looked over it again and found that pins 13 and 15 are also connected to a transistor on the far left side of the driver board. This transistor (C1027) looks like it has been replaced in the past due to its solder joints. This transistor is indicated with the red circle on the attached photo.
The initial path of the 12v B+ circuit is indicated by the yellow lines.
The picture might have to be enlarged to see the drawings
could this transistor be the issue?
The initial path of the 12v B+ circuit is indicated by the yellow lines.
The picture might have to be enlarged to see the drawings
could this transistor be the issue?
reading from the outside leg (closest to the big resistor) in = 7.8V,9.5V,8.5V
The speaker relay was going crazy the whole time as well.
also I accidentally touched the outside leg of the transistor and the big resistor with the probe at the same time, and voila green power light. So I assume the problem is to be found in this transistor or no?
The speaker relay was going crazy the whole time as well.
also I accidentally touched the outside leg of the transistor and the big resistor with the probe at the same time, and voila green power light. So I assume the problem is to be found in this transistor or no?
It seems as if the 3rd leg does lead to the red-ish diode on the edge of the board by the speaker terminals. I had to leave the amp in a different location, but I am going of the picture I have of the board.
I was happy to see the power light turn on earlier but didn't want to leave those parts shorted for fear of damage.
I was happy to see the power light turn on earlier but didn't want to leave those parts shorted for fear of damage.
No. There is like 13M ohms of resistance between the diode and the resistor. The stripped end of the diode seems to run to a leg of a brown pill shaped (capacitor?) and then on to the transistor that has aftermarket solder marks on it.
This is the transistor that was accidentally shorted to the big resistor that cause the power light to come on. I don't know if this just shorted the circuit for the green LED, or this could actually mean something.
This is the transistor that was accidentally shorted to the big resistor that cause the power light to come on. I don't know if this just shorted the circuit for the green LED, or this could actually mean something.
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