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View Full Version : Problem with a 1978 Cobra 148GTL



NY714
07-13-2014, 02:24 PM
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???

BOOTY MONSTER
07-13-2014, 05:05 PM
seems silly , but ..... is your squelch down and RF gain up ?

Tallman
07-13-2014, 05:16 PM
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

NY714
07-13-2014, 08:25 PM
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

NY714
07-13-2014, 08:27 PM
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.