[TowerTalk] Measuring sma relays at UHF

Norm n3ykf normanlizeth at gmail.com
Mon Aug 13 20:58:54 EDT 2018

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.


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?

Norm n3ykf

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