Question about Uniden PC78ELITE 40-Channels Base CB Radio

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When the radio is powered up a a constant buzzing noise is present. This noise is at the same audible tone when the radio is set to any volume level and whether it is set to CB, or weather selection... Thanks

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If this is a high-pitched tone it probaly is from the DC-AC inverter that provides the high voltage to light up the front panel. Normally, this is barely audible, but I've seen a few that are loud enough to be annoying. It may be possible to install a small filter in the power line to the inverter, inside the radio. I've never tried this but if the inverter is the source of the noise, this will be the most practical way to isolate ite & eliminate the problem.
This should onlty be attempted byan experienced CB technician.

Posted on Sep 29, 2008

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