Question about Cobra 148 GTL 120-Channels Base CB Radio

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No modulation lots of signal

Radio was working great i changed antanas and a "freind" said i should tune it up while it was out, so i let him mess with it, now it has great signal on key up butt extreamly weak modulation is there a way i can turn it back up on my own? i dont want to go back to him and hurt his fealings or risk messing something else up.

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It sounds to me if im understanding you correctly, that your friend turned up your carrier? correct? and now the radio isnt as loud? If what im saying is right just turn your carrier back down.
Rollins is correct... but seldom do people have o-scopes and internal precision counters and rf probes. depending on what your friend did .. you may or may not have to send this radio to someone that has a working knowledge of alignment of radios. just remember its woth the little bit of money to have someone that "fixes" radios tune your radio. good luck .. Rick

Posted on Jan 30, 2009

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It really depends on what he messed with while he was inside the radio. If he accidentally turned down the rf output power, you can use an inline rf meter and then tune L37 and L38 for max rf output.

Rollin CBs

Posted on Feb 24, 2008

  • Dean Pitts
    Dean Pitts Feb 24, 2008

    That is the quick and dirty way to turn it back up. The only other way really to do it is to download the factory service manual, from, and then re-align the radio by the factory specs, with the proper test equipment.


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