Jim,
Thank you for your time.
Reference plane was a pair of connectors added to the instrument. Like
this: N Female on instrument. Added: N male to N male, N female to SMA
female. Calibration was performed with a calibrated SMA OSL set.
Calibrated, terminated 50 Ohm, the converted return loss to length=0.
If I leave it open, it gives me 18.3 degrees.
Adding my test cable (1/4 physicial length) give or take adds 120.3 degrees.
There is no howto. Trying to work this out as I go.
Norm n3ykf
On Mon, Aug 13, 2018 at 9:11 PM jimlux <jimlux@earthlink.net> wrote:
>
> On 8/13/18 5:58 PM, Norm n3ykf wrote:
> > Hi all!
> >
> > Playing with my toys.
> >
> > Using an Anritsu S113b which does not have direct voltmeter readout.
> > These numbers were calculated by making a return loss measurement and
> > converting it to relative phase with their Line sweep tools software.
> >
> > I went through this whole process (took about 5 times longer) prior to
> > my trip to 5J0 and realized that mistakes had been made. Took a pair
> > of crossed linear 10 element diddled by a Tohtsu spdt 12v instead
> > Worked like a charm from AOS to 5-7 degrees above the horizon so that
> > I could switch polarities. What a blast. Used my homebrew rotator.
> >
> > https://www.youtube.com/watch?v=1sDP6lAiWGw
> >
> > Please ignore my 2yo little monsters. They can and do make s9+ noise.
> >
> > Trying to get the coax for a cp antenna correct this time. Waste no more
> > coax..
> >
> > I have two Transco SMA 24V relays and an SMA jumper, consisting of two
> > elbows and a straight piece.
> >
> > First order of business was to calibrate all the test gear. Note how
> > long the adapters attached to the N connector were as well as noting
> > the length of the test cable.
> >
> > Got some interesting results:
> >
> > RYA NC: 232.2 degrees
> >
> > RYA NO 231.8 """"""
> >
> > RYB NC 231.3""""""""""
> >
> > RYB NO 231.0 """"""""""
> >
> >
> > SMA jumper to connect Common->NC to NC->common 281.3 degrees.
> >
> > Does this look correct? How does such a small package contain such a
> > lengthy RF path?
>
>
> wavelength is about 70cm, so 1 cm is 360/70 about 5 degrees in free
> space. More like 7-8 degrees in coax.
>
> what was the reference plane for the calibration of the analyzer? The
> spread among paths is <1 degree which is plausible for a small relay.
> I'd expect the path length to be a few cm. You might compare the
> measurement you get with a barrel connecting the two test cables and the
> relay connecting the two test cables (e.g. COM-NC).
>
> a couple feet of coax would add about 200-250 degrees of phase.
>
> >
> > Norm n3ykf
> > _______________________________________________
> >
> >
> >
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> >
>
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