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While working on my first 2970N2, from another techs hands, found the main transceiver unit was getting hot. low output. the IRF520 bias settings were way to high, and one was acting squirrelly, eventually damaging IRF520 Q62. With the shorting board and Q62 removed from the board, I...

hey, are those cigarette burns? or melting from a soldering iron in that one pix.???

oh, when I said "they are cheap" ( IRF520 ) I mean low cost. less than a dollar. a good part. I used to make transmitters with these IRF510 / 520 / 530 / 540 MOSFETs. also good for powering up a relay. Radio Shack used to sell the IRF510.

IRF520's can be blown up easily. but they are cheap. if you give up, let me know. located in SE Louisiana. I need to make some more "beer n pizza money"

I repair these beasts. problems I found. do the tubes get red hot after keying up? zener diode ZD1 shorted. ?? No RF out? maybe resistor R3 is blown open. only half power? RFC-4 or 5 open. need to ground the grids directly. located in SE Louisiana.

I worked on tube amplifiers, but them mobiles have that funky power supply, to convert the 12 VDC to high voltages needed. So if too much work to repair, I take the tubes out, and any good variable capacitors, and throw the rest out. Maybe you have a "Pal" or "Palomar" amp.

old origional post here. popular radio. I am new in WW DX website. I recently was given a broken and modified 148 B made in China. I got it working all stock now. them fat microphones go bad, and speaker audio goes through the microphone switch, which is lousy. audio cuts out. I have the...