John has not said yet what the goal is for his antenna so we are all just
speculating a bit.
It makes a HUGE difference whether you are trying to have an antenna which
is easy to deploy and work all bands, of if you are trying to have a STRONG
SIGNAL on a couple of bands. And for 40m and below, you must distinguish
between whether you are trying to have a strong signal locally, or want to
chase DX.
For all band use, lots of short radials laying on the ground will be a good
compromise.
If your goal is to have as strong of a signal as possible, use elevated
radials - which adds complexity because they must be resonant. However, you
will get outstanding results with just 2 elevated (resonant) radials.
Besides having proven this to myself (for whatever that's worth - hi), take
a look at what the boys of "Team Vertical" (i.e. 6Y4A dxpedition) use, and
what they write about this topic. Their goal was to be portable AND have a
STRONG SIGNAL.
ANYONE interested in having a strong signal from a portable setup should
read what K2KW & N6BT (of Force12) wrote about "Lessons Learned" from their
many Island DX-peditions using only vertical antennas.
You can read it here: http://www.k2kw.com/verticals/learning.html
In particular, read "Lesson #3".
(BTW, if you enjoy reading about dx-peditions, visit K2KW's site:
http://www.k2kw.com/tv.html )
In any case, no matter what you do, John, I'm sure you will have a lot of
fun and learn a lot.
Be sure and share your experience with us, after it is up and running.
Now since James told us what his favorite portable antenna is, I will tell
you mine:
I use a 12m (~40') Spiderbeam telescoping fiberglass pole, I mount a
"non-resonant" vertical dipole to it, 6m of wire per side, and feed it with
300 Ohm openwire. (450 Ohm is as good or better, but heavier). The 300 ohm
twinlead slopes at 45 degrees to the ground (operating table) and is one of
3 guys. Two thin ropes compose the other 2 guys. I need a matchbox of
course, and use an MJF-974B symmetrical matchbox. This works OUTSTANDINGLY
WELL for DX on 40 thru 10m. It also loads and works "OK" (for its size) on
80m. I GURANTEE THIS WILL BE STRONGER/BETER FOR WORKING DX than crossed
horizontal dipoles at this height (and it will stomp all over a coil-loaded
whip).
But if you want to work local stations on 40m, the horizontal dipole as
James describes will blow my antenna out of the water! :--(
73
Rick, DJ0IP
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Richards
Subject: Re: [TenTec] Using an Argosy in the field
I still favor the notion of a push up mast with simple two
wire dipoles - each acting as a guy support - terminating
at the far ends with an insulator, and rope to a ground
stake
like a large, long tent stake, giving you two bands in an
Inverted V arrangement. Cheap, quick, light weight,
easy to deploy, and RESONANT. Similarly the
advantage of
the quarter wave vertical is that it is inherently resonant,
without a coupler- matchbox-tuner-transmatch, whatever
we call it, and even without adding a big coil inductor or
loading coil.
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