DE W3TDH I need a portable HF antenna set up.
Tom Horne wrote:
I am a RACES / ARES member who is trying to actually prepare for
deployment with the ability to carry on effective communications from
anywhere. I'm here in the antenna forum to get advice on a portable
antenna system. I'm not here to join anyones particular theoretical
antenna behavior cult. If you have real world experience with a
portable multi band antenna system that actually worked for you please
share that experience with me.
Hi Tom.
First things first - Are you willing to learn anything? This isn't as
rude as it may first appear. I've had a good bit of experience with
folks in emergency ops who don't want to learn about HF, they just want
a one size fits all answer.
Ive seen a couple of folded dipole antennas advertised that appear to
have some sort of fifty ohm dummy load at the center of the fold. Do
those things do more then provide a heat source for fleeing birds?
They are not particularly good antennas. But they might just be good for
your purpose. They are very wideband, and that may be important if you
don't want to run a tuner. Many of their limitations can be overcome
with applying more power.
Before I get beat up by the antenna purists, the folded dipoles do serve
a purpose of being antennas that you don't have to mess around with. I'd
never own one, but for this purpose, maybe so.
There are several compact vertical and horizontal antennas being sold
complete with stands or tripods are any of them worth their freight?
I suspect that the folded dipole would work a bit better.
The so called spiderweb beams look interesting can anyone offer real
world experience on those?
No experience here, but under emergency condx, it seems like a nuisance.
I'm honestly looking for advice that is based on experience rather than
a particular theory of what should work. I want to know what does work
from real world users.
And yet you came here! Just a joke son...
a few questions might be in order:
Are you looking for rapid setup, or are you going to be in a regular
location with the antenna already in position? You noted deployment, so
I'll assume the former.
For speed of deployment and flexibility, it is hard to beat a general
purpose dipole, ladder line, and a tuner.
It is inexpensive, inherently all HF band, and performs pretty darn
well. You do have to run a tuner, which is pretty simple, but that goes
along with my how much do you want to learn schtick.
All you need is a couple of trees, or even masts, and you can be set up
and running in a short time.
Length of the antenna can be adjusted according to how much space you
have at deployment. Of course, the shorter you make it, the less well it
performs on the lower bands.
I've used these for years, and have talked and buzzed the world over.
I tend to shy away from beams for emergency use, unless I have an omni
or near omni antenna to complement them.
The much maligned Folded dipole would be next on my list. Simple to set
up and use. It isn't as forgiving on length as the general purpose
dipole however.
Those shorty verticals work pretty fair on the higher frequencies, but
are a real b***h on 80 meters. The bandwidth is quite sharp, and can
give you fits.
I use a bugcatcher on 80 in the car because there isn't much
alternative, and I have to have multiple taps to tune 80/75 meters.
Screwdrivers tune more easily on 80/75, but their performance is down a
little from the bugcatcher. I'd steer away from short verticals if you
think you're going to be doing work in that neighborhood.
Hope this helps.
- 73 de Mike N3LI -
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