Question about Cobra 148 GTL 120-Channels Base CB Radio

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Cobra CB After squeezing my microphone to speak I get talk back in my stereo speakers and a screeching noise

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You are getting RF feed back..this can be controlled by the dynamike controll, also you may have the cb mounted close to your stereo. The best way to install any tx/rx is direct connect to you battery (both + and , and suffers from low receive output
(should be about 3 watts) I suspect dried up electro caps is the
problem, as there are heaps in this set as well as heaps of tantalum electro caps (electrolytic capacitors) These cause the set to drift off frequency / power

Posted on Jun 22, 2008

  • flyingfox Jun 22, 2008


    You are getting RF feed back, you should be able to stop this

    by using the dynamike control. Also , the best way to install any tx/rx is both the + and - leads direct to the car battery using an inline fuse. i know these sets, and they are a bugger to generate" whistleup" and also suffer from low voice output.I think

    the problem is they have such a large amount of electrolytic capacitors (including tantalum) and the electrolite has dried up with age causing power down ,and frequency drift. (98% of the parts in these radios are freely available in stores like **** Smith

    or Jaycar Electronice but would be a long job to change all of them, and that may still not fix any problems. But , if you have electronic skills it can be done. because the circuit board is densely packed IT WILL NEED SKILL AND TIME.




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Losed all

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NC Electronic
Mills Wyomign

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