Question about Magnum Minimag Base CB Radio

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No transmit after blown final was replaced.

I explained this on the wrong header. My friend blew the final and I have replaced it with a new one. Also replaced blown power diode and have unit powering up and functioning except....1/10 of a watt is the only reading I am getting on transmit (Should be 5 to 15 watt). I cannot find any board layouts to determine what is what so, I am flying blind. Bias resistors or electrolitics????

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I tried to answer this the first time you posted :). If the finals got burned that bad I found that the bias resistor sometimes will get a burned foil and not make good connection. Also 1/10 watt sounds like the driver isn't amplifying from the buffer. Might want to check for burns on the foil all around the final stages, including where the antenna connector mounts to the board. Don't believe the caps are blown but as a last resort.... Its really hard to troubleshoot without the radio on the bench . Good luck.
Tom

Posted on Feb 05, 2009

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Perhaps a schematic diagram may be of further help.

Good luck and Thank you for using FixYa. Happy Holidays.

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