At 10:23 PM 7/26/97 -0600, you wrote:
>
>The CORRECT base to tip length for a T - top
>loaded vertical of reasonable proportions is
>10% less that a QUARTER wavelength or .225 WL
>
>de Tom N4KG
One antenna that I have found that works is the "MULTEE" that has been in
the Antenna Books for years. The one in the books is made with 300 ohm twin
lead, but mine is made with 450 ohm ladder line. It is 70' horizontal and
52 feet vertical. Thats 122' or close to .225 WL.
Mine is hung off my crank up and fed at 11' with coax thru a current balun
to stop feed line radiation loss. My version has 4 elevated radials each 50
feet long. The are each 1/2 of a Spi-Ro 160 dipole so are tuned to 160.
SWR is 1.35 to 1 at 1840. I plan on using this at my St. Simons Island
house with several radials laid on the ground. It works well altho not as
good as using my tower N4KG style or as my big L. But close enough to work
EU and all 50 states.
The write up says it works on 75/80 but I find a 3:1 SWR so a tuner is
needed and its down 3 to 6 DB from Fritzel FD-4 and my VRD modified Carolina
80 beam with close in stuff and at least 10DB down on EU and SA. That
Carolina 80 is a killer to CE0, LU, and even UA0/KL7 on 75 and 80. K4UEE
said I was the strongest USA on 75 SSB at Juan Fernandez. Wish it was to EU
and JA! Best as I can tell the MULTEE is a loaded flat top for 80 so guess
I can't complain. It is not so noisy on 80 so works well as a receiving
antenna there...better than my 300 ft shielded AB0X loop (too long for 80 to
be effective at removing static).
Working DX on 1/2 acre lot!
Dave K4JRB
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