cobra 142 gtl

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doctor
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cobra 142 gtl

Post by doctor »

I have a cobra 142 gtl base, it powers up and receives, lights are dim and it doesnt transmit am or ssb, any suggestions, I do have a few spare parts

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Rick
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Re: Cobra 142GTL No TX

Post by Rick »

Check Pin 8 of IC5 (MB3756) in TX it should be about 7.6 to 8.2 volts, if there is no volts at Pin 8 then check Pin 5 is going to Ground when the you key-up, if Pin 5 go to Ground and you still have no volts at Pin 8 then change IC5. Lets us know how you get on.
Rick.
doctor
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`42gtl

Post by doctor »

Ok I replaced it and have it working it works on am now on usb it sounds ruff, on lsb its not there, just a ruff sounding weak carrier.

DOCTOR
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Rick
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Re: Cobra 142GTL Weak SSB.

Post by Rick »

It would be best to do a full re-align the PLL section before you go fault finding.
Rick.
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