I now have use of a b-directional coupler for HF and would like to perform the
following 'tests' however I do not understand them. Can you explain the last a
different way. I don't understand "two 50 Ohm loads in parallel with the stub".

Tests of stubs are now clearly reading correct for various lengths across
frequencies. That is once the 1/4 wave is determined the next odd and even
is very predicable.

Thanks,
Dan


Don't you need to measure some "known" loads. Why not try a 50 ohm
load tee'd to a s/c stub (quarter wave at a known frequency) and see
if you get the predictable results at different frequencies around
resonance. Then try two 50 ohm loads in parallel with the stub. (339mm
of RG58C/U should have a Z of around 6000+j0 ohms at around 146MHz, at
half that frequency it should be 0.85+j50, etc...