needle deflection.

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pink148
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needle deflection.

Post by pink148 »

My cobra 148 gtl-dx mk 1 has got a serious problem. As soon as i switch the radio on the signal meter pings off the end of the scale ! the only way to stop it doing this is to move my swr cal switch ! Dont know where to start looking ! any hel would be great !

thanks in advance.
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Rick
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Re: Cobra 148GTL-DX Mk1 full S/meter deflection.

Post by Rick »

Check diodes D7 and D8, maybe short and it could be IC1 which has gone faulty, check the voltage at Pin 5.6. and 7 of IC1, if they differ by more than 2% change IC1.
Rick.
pink148
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Post by pink148 »

Cheers rick for the info..i shall get that checked soon and will post back !
pink148
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Post by pink148 »

Well rick after checking the voltages everything was spot on !
I have found the problem..it was the 100ohm resoistor that is mounted on the swr board next to the antenna socket..now the radio it working fine..it seems to be receiving better than my new ss3900 !
anyway thanks for your help rick..
73s
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