John, G4EIM wrote:
Am I on the right lines, what if I use 4 wires the reason been its better for
guying and I thought the 4 shorter ones mean less cancellation of the vertical
radiator!! Obviously I can use 2 rope for the missing guys but I thought 4
wires may be better
I have not seen any info on using more than 2 wires at least not unless we look
at a horizontal capacity hat constucted with rods and wires.
John,
Your on the right track!
If you go to a four wire top hat, lets say 25 feet each, don't worry
about the exact base impedance. If the top hat is a four wire sloping
affair shorter top hat wires will mean less cancellation and that is
good especially if your guy angle is acute. Pulling the current node up
the pole, so to speak is beneficial and the base match you can take care
of with a simple L network. Some AM radio installations run a perimeter
wire abound around connecting the ends of the 4 wires which is supposed
to gain another 8 to 10 per cent top loading. I would think it would
help but have not modeled this nor have the capability of doing so. It
is a gem that John Mulleny, an superb FCC engineering firm use to
recommend in the 60's.
73,
Herb Schoenbohm, KV4FZ
j
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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