I have quite a bit of test equipment that works very well for me. I will not bore anyone with the model numbers. However, I will say that my weapon of choice to find problems in transceivers is my trusty old Tektronix 465B. I have some frequency counters of course to set those oscillators on frequency and an old fluke digital meter.
I do not repair these radios for any money except parts. I am retired and have enough income to get by. I enjoy repairing my friends radios when they go bad. It is my way of giving back to the elmers who helped me when I was a child trying to do ham radio.
I am currently working on an Icom 751A that appears to have an output transitor bad in the PA. I am awaiting transistors from China. They cost me 20 bucks a piece.
The output from this radio is about 20 watts. It is a good sounding signal. However the output from the twin rf transistors into the big toroidal transformer is not equal. One side is 40 volts P-P and the other is 20 volts P-P. I could not figure out how this could lower the power that much because the normal reading is 30 volts per output transistor. Then I checked the phase. The radio has both signals in phase. They should be 180 degrees apart to get maximum power. So, one of the transistors is mostl likely bad. I ordered two.
Michael
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