cobra 148 gtl

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galaxy
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cobra 148 gtl

Post by galaxy »

i have a cobra 148 gtl, 8719 pll, pcb# ept148112, this radio was made in malaysia in 1995. i have no receive, no transmit on am & ssb. no in coming signal. no movement on the meter. the red & green lite doesn't come on. the pa works, i hear audio when i talk into the mic. I didn't do anything on this radio so far. i would appreciate if someone can give me a hand with this radio. galaxy
ramblingman
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Post by ramblingman »

hi ,,sounds to me like the pll,is out of lock.check your lock detector.
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Rick
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Re: Cobra 148 gtl Dead

Post by Rick »

Sounds like IC4 (MB3756) is dead, also check TR35 (2SC945) and D55.

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galaxy
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cobra 148 gtl

Post by galaxy »

thank you for your reply. i changed ic 4 3756, tr 35, d55 still no luck. galaxy
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Rick
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Re: Cobra 148 gtl Dead

Post by Rick »

Ok then what is the voltages at IC4 Pins 1,2,5,6 and 8 in RX and TX.

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galaxy
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cobra 148 gtl

Post by galaxy »

thank you, rick i burnt the trace this one is junk.... i will try a different radio? galaxy
tim_spur
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Post by tim_spur »

dont junk it you can solder you a wire from where the trace burnt to the end of where the trace runs kinda like running a jumper wire
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