Once you get this figured out it would be a huge help to the TenTec
community if you would write up your findings.
I'm sure it would help others. I've dealt with a few PLL problems and
information is scant. I do suspect part of the problems are due to crystal
aging. I believe they get so far off frequency that the VCO has a hard time
pulling them back.
Steve N4LQ
On Sat, Dec 10, 2016 at 10:59 PM, Dukes HiFi <dukeshifi@comcast.net> wrote:
> Actually the synthesizer in this radio is pretty simple by synthesizer
> standards.
>
> It is also rather ingenious.
>
> I have found that the CPU puts more of these in the parts bin than
> synthesizer issues.
>
> But, we all have different experiences. For me, I’d rather wrestle an
> opponent I can beat (a PLL synthesizer) than one I cannot (a CPU with
> proprietary chips you can no longer get at any price).
>
> 73
>
> Gary
>
>
> > On Dec 10, 2016, at 12:56 PM, Steve Ellington <steven4lq@gmail.com>
> wrote:
> >
> > Good luck. PLL problems are the reason so many Omni VI's get sold for
> > parts. :*)
> >
> > On Sat, Dec 10, 2016 at 1:15 PM, Dukes HiFi <dukeshifi@comcast.net>
> wrote:
> >
> >> I did find the Omni 5 process that Barry had referenced but this only
> >> covers centering of the VCO.
> >>
> >> I need to do the loop IF alignment.
> >>
> >> There is a rectifying test point at the output of this stage and I
> assume
> >> that there are adjustments to be made at differing frequencies using
> the DC
> >> voltage developed at this test point in order to get proper gain across
> the
> >> entire required bandpass of the VCO.
> >>
> >> That’s the process I need.
> >>
> >> Thanks,
> >>
> >> Gary
> >>
> >>
> >>> On Dec 10, 2016, at 12:07 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
> >>
> >> _______________________________________________
> >> TenTec mailing list
> >> TenTec@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/tentec
> >>
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|