First I replaced the PLL chip itself. Then I found an open 10 ohm resistor in
the drawing line for the loop IF. I replaced that and also the BF988 IF FET.
I performed a “rough” alignment of that stage to get enough signal through it
to get it to lock on most of the band.
I assume this is a stagger tuned bandpass amplifier with a bandwidth of about
10 MHz, much like a 45 MHz TV set IF back in the day.
Ideally a sweep generator would be required to properly align such an
amplifier. I do have a means to provide a sweep generator of the proper
frequency but need to know which of the cans to peak for which portion of the
passband.
Gary
> On Dec 10, 2016, at 1:02 PM, Mike Bryce <prosolar@sssnet.com> wrote:
>
> wondering what was the repair on the PLL?
>
> Mike, wb8vge
>
>
> Mike, WB8VGE
> SunLight Energy Systems
> The Heathkit Shop
> http://www.theheathkitshop.com/ <http://www.theheathkitshop.com/>
> J e e p
> o|||||||o
>
> A man with one clock knows what time it is. A man with two clocks is never
> sure.
>
>
>
>> On Dec 10, 2016, at 1:07 PM, Dukes HiFi <dukeshifi@comcast.net> wrote:
>>
>> Now that I have repaired the PLL on the 5.5 mHz board of this Omni 6+ I am
>> repairing, I need to align the loop IF amplifier and VCO centering.
>>
>> Is there a resource where I can find this process?
>>
>> Gary
>>
>> W0DVN
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>
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