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Arc uses 30 ohm resistors on many of their snubbers. Did you desolder it and measure its resistance?
Can you post a photo of the entire board?
Can you post a photo of the entire board?
The following is probably about the same as what you have. You can see that it uses two snubbers. If the discolored resistor has changed in value, the capacitor in series with it may be shorted or leaky. If it's not well out of tolerance, it's likely that it simply operates at a very high temperature. If that's true, replacing it with one of equal or higher power rating and installing it with long leads may help protect the board from thermal damage.
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It still measures 30.5 ohms..
All outputs and power supply fets test fine..
The protection light is flashing..
Any ideas what to check since i cant seem to find the fault why its stuck in protection mode??
All outputs and power supply fets test fine..
The protection light is flashing..
Any ideas what to check since i cant seem to find the fault why its stuck in protection mode??
I don't have anything specifically on this amp. If you trace the circuit back from pin 9 of the 3525, does it lead to an opto-coupler (maybe via a 390 ohm resistor)?
Removing that resistor should defeat the protection circuit (be careful) to allow you to see what sort of fault is causing the problem.
Pin 1 of the NPN transistor (MPS651) should be directly connected to ground. Check for a bad solder connection or a burned trace.
I must not have the right transistor because pin 1 of the MPS651 connects to the positive side of a cap
OK I found the other transistor..
MPS751
Pin 1:13.78
Pin 2:13.90
Pin 3:0.44
MMBTA06
Base:13.90
Emitter:0.00
Collector:0.00
MPS751
Pin 1:13.78
Pin 2:13.90
Pin 3:0.44
MMBTA06
Base:13.90
Emitter:0.00
Collector:0.00
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