Carl, the reason I mentioned the 20db or so polarization loss is that
without that loss the power required from your 2n2222 is decreased by 100
times, for the same FS meter reading. If you have found that 100 mw gives
a satisfactory level, and if you match the polarization, you should find
that 1 mw will do the same. That's a big reduction in possible QRM. Also,
you want vertical polarization of your test signal so that you won't
inadvertently measure the response of your system to horizontally polarized
signals. To put it another way, measure vertically polarized antennas
using vertically polarized signals, and measure horizontally polarized
antennas using horizontally polarized signals.
In Vietnam and Thailand, we used polarization diversity systems. That
means separate transmitters and receivers, and separate feedhorns polarized
both vertically and horizontally. You could watch the signal fade almost
completely out on one polarization, and at the same time the opposite
polarization would maximize.
When you say the experts have said that a db loss at any angle is a db
loss, I think what they are talking about is that ground losses produce
proportional signal loss at all propagation angles. That is not the same
as all polarization angles, which refers to the direction of the E field.
73
Larry, N9DX
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