Ive got this amp, a bit un-familiar. The driver board is epoxied. The amp attempts to power up for a brief few seconds but then falls straight into protect. All transistors are measuring OK and everything seems well enough in-order on the pcb. Any thoughts as to why it stays in protect?
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There is a page for this amp in the PA folder.
You can often tell if the drivers are defective by measuring the resistance between the gate and source of the output transistors.
You can often tell if the drivers are defective by measuring the resistance between the gate and source of the output transistors.
I see that now thank you.
On about half the output fets, between gate and source measure about 29k. On the other half, Im seeing 570ohms. So one of the drivers has failed from overheat?
On about half the output fets, between gate and source measure about 29k. On the other half, Im seeing 570ohms. So one of the drivers has failed from overheat?
It likely failed. Possibly from overheating if you don't have any failed FETs.
If you measure and cut along the line made with the dial caliper, replacing the IC isn't that difficult. Don't go any farther than necessary or you will likely end up disturbing other components.
If you measure and cut along the line made with the dial caliper, replacing the IC isn't that difficult. Don't go any farther than necessary or you will likely end up disturbing other components.