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Old January 27th 15, 09:57 PM posted to rec.radio.amateur.antenna
[email protected] jimp@specsol.spam.sux.com is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Radials and Verticals

Irv Finkleman VE6BP wrote:
I read an article somewhere, likely an antenna book, that you can get
away with short radials on a short loaded antenna as long as they
are at least as long and the antenna is high.

On my tiny 6ft by 10 ft by 10 ft high balcony I plan to deploy a
multiband antenna (by Superantennas) which is center loaded, with an
adjustable loading coil. The antenna when fully extended is
about 9 ft high. I am going to cut and attach about 8 or 10
radials, all about 10 feet long. They will have to be laid in
a relatively random pattern since the antenna will be located
in about the center of the balcony. I cannot have anything
extending or dangling off the balcony.

Once I have those short radials in place, I plan to cover them
with a piece of outdoor carpeting to hold them in place, and in
order that I can still step out on the balcony without disturbing
them or hopelessly entangling myself among them.


Since you plan on covering the wires anyway, you might concider looking
for cheap chicken wire to cover the entire deck, which at HF will look
like a solid metal plate.

Also, after you connect the antenna ground to whatever you wind up with,
check the SWR then add a second temporary connection and recheck the SWR.

If the second connection makes a difference, make it permanent and repeat
until additional connections make no difference.

I have a backyard vertical with all the radials tied to a common plate
with the plate tied to the antenna ground. There was a significant
difference on the upper HF bands between one and two tie wires, no change
with three. Even a straight wire has inductance...


--
Jim Pennino