cobra 142gtl no transmit or receive audio

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mechanic
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Joined: Monday 14th Aug 2006, 14:06
Location: jacksboro

cobra 142gtl no transmit or receive audio

Post by mechanic »

I have a cobra 142 gtl that I purchased from a friend. I dont know the history of the radio. The radio lights up the meters dont move and I cant get it to key up. I have no sound from the speaker. When I key the mic the transmit light dont come on. What is the best place to start aon this radio. I have some electronic knowledge but limited tools to work with.
Thanks for any help
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Rick
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Re: cobra 142gtl no transmit or receive audio

Post by Rick »

Check IC5 (MB3756) and TR37 (2SC945) common fault on this radio. Back in the 70s I used to repair quit a few Cobra 140/142 GTL and when they came in with no RX TX it was IC5 or TR37. Hope this helps, let know how you get on.

Rick.
mechanic
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Joined: Monday 14th Aug 2006, 14:06
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Post by mechanic »

Thanks Rick for the help . I replaced ic 5 and tr 37 no change. The radio makes no sound at all. any other suggestions . Thanks
mechanic
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Posts: 6
Joined: Monday 14th Aug 2006, 14:06
Location: jacksboro

Post by mechanic »

Thanks Rick for the help . I replaced ic 5 and tr 37 no change. The radio makes no sound at all. any other suggestions . Thanks
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