Question about Cobra 200 GTL DX 4-Channels Base CB Radio

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Cobra 200gtl High Power Transmit problem??

This radio connected to a 25 amp power supply and running high power on Cobra 200gtl.. When transmitting,on high power, the needle moves properly and output power is good for a few seconds then within 2 seconds the power drops off rapidly , needle in meter then does slowly drop away under ssb modulation till it does not react at all. On low power the transmitter is ok ....Any solutions??

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  • ozradio123 Sep 26, 2008

    thanks for the advice


    the problem was the RF Transistor (RF16FF1) was loose and overheating . now fixed thanks


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Depending on the type of power supply, radio frequency (RF) energy from the transmitter may be 'fooling" it into thinking that you're overloading it. Check to see if there's any discernible dimming of the meter lamp when this problem occurs, if so, the supply is the culprit.

Otherwise, its probable that the final amplifier transistors are overheating, either they are 'leaky' or not properly attached to the heat sink.

Posted on Sep 26, 2008

  • 1 more comment 
  • stratomas59
    stratomas59 Feb 18, 2014

    There were severalhundred radios maybe a couple of years worth and I don't know what years they were but that is a very well known problem with some of the Cobra 200 DX gtl's that had this problem along with a few more. Later rewvisions were fixed for that problem as well as some other problems. I think that most of the later model revisions had most problems fixed. I habve been tol;d by radio techs that 2007 was the last year that Cobra made them and supposedly by then most all if not all of them were working good. Unless you are a compentent radio tech my suggestion would be for you to take the 200 to a tech and explain your problem. I know it can be fixed. Bob

  • Kelvin bell
    Kelvin bell Mar 23, 2014

    Could it be the power output is to high at 120watts ssb?

  • Kelvin bell
    Kelvin bell Mar 23, 2014

    Ok thanks bob,it sure is a pain.

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