Question about Cobra 25 LTD 40-Channels Base CB Radio

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Cobra ltd classic no modulation

Cb has tx and rx.. Keys about 4 watts but that's all the power it has and no modulation swing. Friends say they can hear me but Im very fant. The modulation limiter has been cut in this radio also..Any help
with this radio will be appreciated thanks

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  • axl4life666 Sep 23, 2008

    COBRA 25 LTD CLASSIC

    cb has tx and rx.. Keys about 4 watts but that's all the power it has
    and no modulation swing. Friends say they can hear me but Im very fant.
    The modulation limiter has been cut in this radio also..Any help
    with this radio will be appreciated thanks

  • axl4life666 Sep 26, 2008

    I SOME WORK ON CBS BUT HAVE NEVER RUN INTO THIS PROBLEM BEFORE. COULD YOU TELL ME WERE THIS IS LOCATED?

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Assuming that you've tried another mike, the problem may lie in the speech amplifier circuit within the radio, something that will require someone with technical knowledge to repair.

Posted on Sep 26, 2008

  • David Eisenberg
    David Eisenberg Sep 29, 2008

    The speech amplifier is transistor TR-13 & the components around it. Electrolytic capacitor C-94 could be shorted, depriving the circuit of power.

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Mar 12, 2008 | Cobra 29 WX NW ST 40-Channels Base CB...

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