When I put up my quad, I checked the resonance at the feedpoints using an
Autek RF1. I used a couple of inches of wire to attach the RF1 to the loop
feedpoints. Some of the results did not seem correct. The SWR was OK at the
shack and the quad played well. A friend had a similar experience. Here is part
of his message: to me:
-----------------------
I made the mistake of trying to measure impedance/resonance right at the
feedpoint with the Autek RF1. I knew from experience with the 40
dipole that that's a bad thing to do. I'm not sure quite why. So I did two
other things. I had an old Johnson Directional coupler. I stuck it right at the
feedpoint (6" coax actually) with the signal lines running down to the ground
and got readings that made much more sense. I also cut a 1/2 wave piece of RG8x
and put the Autek at the end of that. It essentially reproduced the coupler
results. It seems one can't make measurements and BE at the feedpoint as well.
Body capacity effects I guess. --------------------------
Have others had this experience. Does body capacity cause it?
73,
K5ESW
Paul
Paul.Ferguson@pobox.com
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