cobra 18 ultra w/weather no rx or tx

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breakdown5
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cobra 18 ultra w/weather no rx or tx

Post by breakdown5 »

hello again. cobra 18 ultra...no rx/tx but weather band works fine... had a bad final i think... replaced final trans and resistor next to it along with the driver trans but ng ??? any ideas.... when i key the tx light does come on but no power output at all? thanks! :shock:
ouxly40
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18

Post by ouxly40 »

If that model has the little stand-up boards - there is your problem. Re-solder them.
breakdown5
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Post by breakdown5 »

no stand up boards.. but thanks!
breakdown5
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Post by breakdown5 »

no stand up boards.. but thanks!
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Rick
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Re: obra 18 ultra w/weather no rx or tx

Post by Rick »

If the radio has a SM5123A PLL. Check D18, D19 and IC5 if one or more have failed then you will have on RX and TX.

Rick.
breakdown5
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Post by breakdown5 »

my cobra 18 ultra has a lc7185 pll so not sure where to look. thanks rick for the info!! :?:
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Rick
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Re: obra 18 ultra w/weather no rx or tx

Post by Rick »

Do you have the schematic diagram for the radio?

Rick.
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