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Cobra 148 GTL power issue

Crambone

Well-Known Member
Jan 22, 2019
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156
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Friend dropped off his 148GTL for me to look at as he wired neg and pos backwards. I checked main fuse on the power wire and it had a 10amp blown in it!! So my first guess was D55 and I found it shorted closed not open. I replaced and still nothing but I’m seeing 12vdc everywhere in the radio even places I believe it shouldn’t be?
Any suggestions where to take a look?
 

Friend dropped off his 148GTL for me to look at as he wired neg and pos backwards. I checked main fuse on the power wire and it had a 10amp blown in it!! So my first guess was D55 and I found it shorted closed not open. I replaced and still nothing but I’m seeing 12vdc everywhere in the radio even places I believe it shouldn’t be?
Any suggestions where to take a look?
1st thing i would do is use like a 1 amp fuse while trying to find the problem also check the voltages at the mb3756 regulator at pin-2 the wrong amp fuse was put in there which caused more problems compared to just the fuse and d55 to blow with way fewer problems
 
Last edited:
Friend dropped off his 148GTL for me to look at as he wired neg and pos backwards. I checked main fuse on the power wire and it had a 10amp blown in it!! So my first guess was D55 and I found it shorted closed not open. I replaced and still nothing but I’m seeing 12vdc everywhere in the radio even places I believe it shouldn’t be?
Any suggestions where to take a look?
there is (by the transformer) another (glass looking) diode next to it.. replace it.
 
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