Uniden PC78LTW cooked

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rac29fan
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Uniden PC78LTW cooked

Post by rac29fan »

Well yes I did, I hooked my PC78LTW up to a trickle charger thinking I could power it up that way. Your right I fried it. Any idea what diode I need to look at :?:
timrim
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Post by timrim »

The polarity diode is almost certainly toast. You can find it by following the radios power wires down to the board. It will be a black diode, more than likely, it may be cracked down the middle. If the diode is shorted, then the rest of your radio is probably ok.

Trickle chargers are very unpure and unfiltered DC, they have an AC component to them which is why it fried your radio.
rac29fan
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Post by rac29fan »

Ok thanks. I'll try that in the next couple of days and let you know.
frogman296
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Post by frogman296 »

d17...it is in the rear by the transformer...1n4004 is the diode number
rac29fan
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Post by rac29fan »

Ok it was D23. I replaced it and it's working great. 2@ $0.99 at radio shack. Thanks for the help.
Another thing I'm trying to learn is positive side and neg. side. I have a Cobra 25 that I tinker with trying to learn. I lifted the foil trying to add a swing kit. How do I identify where to hook up a jumper wire.
frogman296
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Post by frogman296 »

rac29fan wrote:Ok it was D23. I replaced it and it's working great. 2@ $0.99 at radio shack. Thanks for the help.
Another thing I'm trying to learn is positive side and neg. side. I have a Cobra 25 that I tinker with trying to learn. I lifted the foil trying to add a swing kit. How do I identify where to hook up a jumper wire.
my d was for a cobra 29, my bad...you mean you want to fix the trace??
rac29fan
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Post by rac29fan »

I don't know what you call it. (Mabey a trace.) I removed a jumper and damaged the green foil in that 1 spot. I understand I need to soulder a jumper to another point. How do I identify what point that will be?
frogman296
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Post by frogman296 »

are you wanting to still install the swing kit??

if you are just gonna install the jumper back in..solder it in the same area of the foil(wheres its lifted) then to the other hole...you can do this on the foil side of the board
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