Question about Cobra MR- F55 Base CB Radio

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Low transmitting range on Cobra MRF55

The radio worked fine for about 6 months and now I can only transmit about 300-500 feet. All incoming traffic is clear for miles and no problems receiving transmissions, only when I try to call out. Any suggestions? Thanks

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  • dstrand Jan 01, 2009

    The radio is in my boat and nothing has been altered or added or deleted. It worked fine for a few months and then just quit transmitting for any kind of distance over 400-500 feet. All incoming transmissions are fine. Thanks again for your help

  • dstrand Jan 02, 2009

    What would some of the other things be?

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Hi dstrand, sorry you are having a problem. I will need some more info if you can. Is this radio in a base situation or mobile? Have you had any work don recently? Have you changed anything on the system? (Microphone, antenna, coax, etc)

Haave you checked your swr recently/ If yes, did you use a seperate meter or did you use one built in the radio?

Hope to hear from you soon.

Tom

Posted on Jan 01, 2009

  • Tom Arsenault
    Tom Arsenault Jan 01, 2009

    Not having the radio in front of me I can only guess. From what your saying, I would say 85% cahnce you blew a final. You probably only pushing 1/4 watt at the driver thats why the short distance.(about 30-60 dollars to fix at a shop)

    There are other things that could cause this but the finals are the most common.

  • Tom Arsenault
    Tom Arsenault Jan 02, 2009

    Voltage to the buffer and or driver and final, A intermitent open at the so-239 ( antenna connector at the pcb, You said the radio is in a boat, could corrosion at the antenna be an issue? How old is the coax? Did the insulating washer on the antenna mount break off? Lots of things to troubleshoot, but very hard not having the radio. Good luck and thanks for using Fixya!

    Happy New Year,

    Tom

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