This is an interesting post!
As far as dipoles are concerned.....Some years ago, I was operating portable
with a Ten-Tec PM3A (40/20m.) and then the first "Argonaut" they built.
Some of my best results was with "loaded dipoles". Dipoles very short for
the given band I was operating on. I remember the 40 meter one was about
15' long overall. It consisted of a center section of about 5-6' each leg,
the loading coil (in each leg) then the last 12-15" of wire...mainly a
"tuning stub" so to speak. The loading coils were wound on 3/4" polystyrene
tubing forms. Antenna elements were #24 hookup wire. Feeder was a short
length of RG-74/U (LOSSY on the higher bands!) They were erected from 6'
to around 15' high. The tuning was VERY sharp, you could move maybe plus or
minus 10-15 khz or so for around a 1.5:1 VSWR... They did work better than
any vertical whip I tried.
On the other hand 20 years later (NOW!) I found it difficult to setup such
an antenna EASILY in say a parking lot or a cow pasture (no trees!) The 33'
Fiberglass pole is easy to setup and does work, albeit not the best there
is!
I have never tried the "commercial" loaded dipole antennas like the
"Buddipole"? Had an idea to use something homemade and similar using some
telescopic "inner elements", easy to change "loading coils" and telescopic
end elements in a "loaded rotating dipole" configuration, but never got
around to doing this! Something less than 20' long on 80 and less on the
higher bands, light and easily transportable, easy to setup, maybe using the
fiberglass mast not quite telescoped to full height...(25'?) to take
advantage of the stouter section below the "fishing rod" tip sections.
(This is the MGJ 33' pole)
The BIG disatvantage of the loaded antenna was a narrow bandwidth,
especially with hi-Q loading coils. Someday maybe I'll try it again
configured as outlined above.
73,
Sandy W5TVW
----- Original Message -----
From: "Mike Morrow" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, March 04, 2008 6:23 PM
Subject: [Elecraft] Re: Mobile/portable antennas
. I have used this very expensive combo a
number of times in the past seven years at campsites in the Arkansas
Ozarks
and the Tennessee and Alabama Appalachians. For comparison purposes, I
also
set up a simple home-made multi-band wire dipole ($20) at nine feet above
ground.
I made contacts on 40m through 10m using both antennas. In *EVERY*
instance,
on *EVERY* band, the vertical installation was 2 to 4 **S-units** lower in
receive and transmit performance, compared to the dipole. I found NO
exceptions
to this.
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