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Thread: Problem with a 1978 Cobra 148GTL

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    Question Problem with a 1978 Cobra 148GTL

    Any idea's what may cause me to totally loose receive on SSB, I see tranmit but can hear anything on LSB???? AM works great no problems at all. Wonder id just a capacitor or something simple???
    RCI-2950DX, 1978 Cobra 148 GTL Taiwan, SHURE526T MIC, Tug-8 With Astatic 10 DA Head, Astatic 575M6, ASTRON 70/20 AMP POWER SUPPLIES, IMAX 2000 W GROUND PLANE KIT. TIMES MICROWAVE LMR-400 COAX, RF CHOKES. DIAMOND SWR/POWER INLINE METER. 250 of Sea Level Under Me. Recent World Radio Member.

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    seems silly , but ..... is your squelch down and RF gain up ?

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    Quote Originally Posted by NY714 View Post
    Any idea's what may cause me to totally loose receive on SSB, I see tranmit but can hear anything on LSB???? AM works great no problems at all. Wonder id just a capacitor or something simple???
    Does USB work? With AM/LSB/USB there many things that can go wrong. Check your function on USB receive and transmit. I think all radios are the same in that alignment procedures address AM first and then the SSB. A small adjustment can make a huge difference in receive or not. If you have technical skills and tools the Service manual has the voltages of all of the transistors in the receive and transmit state. A huge help if you are digging around a radio you aren't familiar with.

    Full service manual: http://www.cbtricks.com/radios/cobra/148gtl/index.htm
    Last edited by Tallman; 07-13-2014 at 05:26 PM.
    All answers are opinions and may, or may not be technically correct.

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    Quote Originally Posted by Tallman View Post
    Does USB work? With AM/LSB/USB there many things that can go wrong. Check your function on USB receive and transmit. I think all radios are the same in that alignment procedures address AM first and then the SSB. A small adjustment can make a huge difference in receive or not. If you have technical skills and tools the Service manual has the voltages of all of the transistors in the receive and transmit state. A huge help if you are digging around a radio you aren't familiar with.

    Full service manual: http://www.cbtricks.com/radios/cobra/148gtl/index.htm
    Thanks but no usb either, will take your advice. Thanks
    RCI-2950DX, 1978 Cobra 148 GTL Taiwan, SHURE526T MIC, Tug-8 With Astatic 10 DA Head, Astatic 575M6, ASTRON 70/20 AMP POWER SUPPLIES, IMAX 2000 W GROUND PLANE KIT. TIMES MICROWAVE LMR-400 COAX, RF CHOKES. DIAMOND SWR/POWER INLINE METER. 250 of Sea Level Under Me. Recent World Radio Member.

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    Quote Originally Posted by BOOTY MONSTER View Post
    seems silly , but ..... is your squelch down and RF gain up ?
    Thanks but that was the first thing checked, also radio was left in car for like 3 days in row and inside of car got very hot in sun, probably over 100 Degree's, which I am thinking may of melted or damaged something in radio.
    RCI-2950DX, 1978 Cobra 148 GTL Taiwan, SHURE526T MIC, Tug-8 With Astatic 10 DA Head, Astatic 575M6, ASTRON 70/20 AMP POWER SUPPLIES, IMAX 2000 W GROUND PLANE KIT. TIMES MICROWAVE LMR-400 COAX, RF CHOKES. DIAMOND SWR/POWER INLINE METER. 250 of Sea Level Under Me. Recent World Radio Member.

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