Bill, the fix is to remove the major loop board, unsolder the shield
on the bottom and reflow all of the solder connections. I had the
problem on 1 or 2 bands, but eventually all 4 PLL circuits needed
solder reflow. For good measure, I sealed the little exposed coils
and transformers with clear nail polish and replaced the aluminum
electrolytic caps with tantalum types because both coils and caps
seemed to be microphonic. The root of the problem is cold solder
joints caused by tarnished tinning on the board or component leads.
The MInor Loop board may require the same treatment. It depends on
whether you have problems on all bands or just some.
I have had no further PLL problems since I reflowed the boards. Also,
some versions of the Paragon have a small trimmer pot on the
Major Loop Board that may need a small tweak.
73, Bob WB2VUF
Bill Capps wrote:
>
> hello all
> what is done to cure the "phase lock loop" ailment in paragons.
> currrently
> my paragon goes into phase lock loop mode when i attempt to band change to
> 160 or 80 meters.
> beginning to look like UPS trip to dolly parton blvd
>
> 73
>
> bill capps
> af4od
> auburn,alabama
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