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Old June 4th 07, 12:16 AM posted to rec.radio.amateur.antenna
[email protected] nm5k@wt.net is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 757
Default Metal mast for inverted V antenna support--will it work?

On Jun 1, 2:43 pm, wrote:
What is the result of using a metal mast as the center support of an inverted V
antenna. Will it work and if so can resonable low SWR be obtained using a
tuner? Any advice appreciated.

TIR


I actually prefer a metal mast. In case of a lightning strike, the
mast
takes the bulk of the energy to ground, instead of my coax doing all
the
dirty work. A vertical on top of the mast can act as a lightning rod,
so all bets are off on those. But with my coax supported a foot or so
below the tip of the mast, feeding dipoles, I've taken strikes with no
coax
damage so far. There is some energy that runs the feedlines, but it's
fairly
small compared to the mast itself. It's enough to make an audible arc
sound
at my coax/bulkhead ground connection though. Thats with the
connectors
screwed in too.. I've never noticed any real RF coupling problems with
a
metal mast. You will see that with metal that parallels the antenna
legs
themselves. One of the worst coupling problems I ever saw as far as
tuning, was with a set of dipoles used next to a large mobile home.
All that metal surface gave us a fit. I had to try quite a few leg
locations/wire
lengths before I could get it tuned halfway decent. That was one of
the
rare cases I've seen where even the lowest band had problems.
MK