wrote

Cecil Moore wrote:
I rigged up a 6m dipole yesterday with current pickups driving equal
lengths of coax. Remember, we are not discussing the accuracy of
my magnitude measurements, only of my phase measurements.

What was the indicator? What was the coupling device?

I have an assortment of toroids of various materials from Amidon. I'm
at work right now and I don't remember if I used 43 or F material.

On six meters, it would take a darned small probe and indicator to not
greatly perturb the system.

They are small toroids. I chose 6m because the dipole area was
physically small.

If I was going to test something like this, I'd use a small indicator
hanging from the antenna and do it on a low frequency.

Please feel free to make that measurement. W7EL just reported that
EZNEC agrees with my phase measurements. So does Kraus.

So, tell us about the probe and indicator.

Similar to the ones W7EL used. They were calibrated within one turn
of each other. The signals at the ends of the coax lines were calibrated
for equality in magnitude and phase. Magnitudes are a relative measurement
but phase was not. I ran the experiment two ways.

One was Lissajous figures on my 100 MHz Leader. The other was putting
the two samples in opposite phase to each other, i.e. phasor subtraction.
For small angles, the angle is equal to the sine of the angle so the
addition
of two coherent sine waves yields an amplitude proportional to the phase
difference when the phase difference is small. The phase difference was
so small it was virtually undetectable.
--
73, Cecil, W5DXP