power regarding frequency

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frogman296
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power regarding frequency

Post by frogman296 »

i have great power on a uniden pc76, that is until i go past channel 24...then i have NONE...no power whatsoever

any help would be appreciated.

thanks fellas..
ramblingman
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Post by ramblingman »

Have you had an extra channel (expo) kit installed???
One of the crystal oscillators might be adjusted right
at the critical peak.And the oscillator might not be
starting every time.Such coils should be set just past
peak on the inductive (slow tuning) side of the oscillator.
Screw the slug into the coil just alittle bit further.
frogman296
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Post by frogman296 »

nothing of the sort has been done to the radio...baffles me..
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Rick
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Re: power regarding frequency

Post by Rick »

Check the PD coming out of the PLL, the voltage should go up has you go up through the channels.
Check the VCO.
Check the Fin.

I do not know what PLL is being used as you have not given all the info required.
See www.radiomods.co.nz/forum/viewtopic.php?t=312
Rick.
ramblingman
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Post by ramblingman »

Frogman you can disreguard my previous post.
Sorry my mistake,,Somehow i thought it was
a 148.The pc76 is the equal to cobra 29..
Follow ricks suggestion.Check pll pin voltages
while turning channel selector.Also as he says check
the v.c.o. voltage.
frogman296
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Re: power regarding frequency

Post by frogman296 »

Rick wrote:Check the PD coming out of the PLL, the voltage should go up has you go up through the channels.
Check the VCO.
Check the Fin.

I do not know what PLL is being used as you have not given all the info required.
See www.radiomods.co.nz/forum/viewtopic.php?t=312
my apologies rick and admin

you can delete this topic...i have decided to put it on the scrap pile

thanks
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