[TowerTalk] Relay Box Measurements

[Jeff DePolo]

> when you do the measurements (using some form of VNA, I 
> presume), do you 
> cal with a set of standards with UHF connectors, or something else?

You're better off using lab-grade test cables with constant impedance
connectors (N, SMA, TNC, etc.) and a precision cal kit to do the cal, and
then use a high-quality adapter to get to UHF to connect to the DUT.  Unless
you're dealing with short wavelengths, the added electrical length of the
adapter (maybe 3/4"?) isn't appreciable (3/4" is only a little over half a
degree at 10m), but if you're a purist you could always offset the complex Z
accordingly (Smith Chart or electronic equivalent thereof). Insertion loss
of a quality N to UHF adapter is negligible at HF.

				--- Jeff WN3A