Hmmmm???! I just planted a used HyGain HyTower in the backyard. Their
instructions direct you to use 6 8' ground rods in a pattern at the base of
the antenna, about 24" out, all tied together with #8 or so buss wire. It
seems to work. Is that because the antenna is so lossy the VSWR only
appears to be good but the radiation efficiency is really dirt (!) poor? I
have worked JA's with 100 watts from the Wilds of Maine, which, I realize,
may be as scientific as the antenna articles found in 73 magazine....
At 10:17 PM 10/7/1999 -0500, you wrote:
>Rods driven into the ground have absolutely nothing to do with making
>an RF counterpoise or RF "drain." Ground rods serve only one purpose,
>and that is to protect your equipment from lightning damage.
>
>Polyphaser produces a good book on the subject of grounding, and
>shows how good engineering practice will pay off when the storms come
>your way.
>
>Ground radials, or a ground screen under an antenna system handle the
>RF end of things at a radio station. Rich is correct; they may lay on top
>of the ground, or be buried a few inches, it makes no difference. The
>reason radials are buried is to make the landscape look better at the
>antenna farm. Relying on ground rods to serve in place of a proper
>RF ground sends valuable RF into the lossy earth instead of its intended
>destination.
>
>(((73)))
>Phil, K5PC
>
>
>
>
>--
>FAQ on WWW: http://www.contesting.com/ampsfaq.html
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
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>
>
73 from NS1Z, FN44rn
John Wilcox
871 Route 120
Rumford, ME 04276-3836
fon: 207-364-2246
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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