Wharfedale 2800 pro amplifier get very hot when I turn it on, so I decided to test the channels one by one and I discovered that the channel A is the curse, Because immediately I plugged the A channel it will get hot but if remove it, it became normal, and when I try troubleshort on the output transistors on board, they all seems ok on board.
Please I need directions on the next steps to take.
Thanks.
Comments
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0
Hello,
I would check the output with scope (DC,high frequency excitation)and the output transistors
separately.Are the power supply voltages on the emitter resistors OK?Are the A and B Curve OK?
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Thanks for the contribution, that what I am doing now checking the output transistors separately, but I don't have scope. Talking about the supply voltage on emitter resistor, I don't really know how to do that. Do you have any idea on the voltage range that suppose to be present in emitter resistor?
and how to test it.
0
Thanks for the contribution, that what I am doing now checking the output transistors separately, but I don't have scope. Talking about the supply voltage on emitter resistor, I don't really know how to do that. Do you have any idea on the voltage range that suppose to be present in emitter resistor?
and how to test it.
0
Hello,
Check the voltages on the emitter resistor chain (0.22 ohm 5w) (dummy load,zero volume)
If the transistor is faulty,higher current flows,and higher voltage can be measured. (0-1V)
Are the QA 26 and QA 37 OK?
TJ
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