[ILQSO] "Best" all round portable antenna

Tue Oct 24 19:59:14 EDT 2006

 Hank, you and I have a lot of parallel experience.  Years ago I used a 140' dipole fed with good quality Belden UHF TV twinlead and a tuner that I built while in high school.  The tuner used four alligator clips to find the best taps and works great, just somewhat cumbersome to tune.  At home I have an 80m dipole fed with cheap Radio Shack TV twin lead and a Johnson Matchbox.  

That old dipole still gets used today for FD.  It really performs with the center and ends at 50'.  An automated tuner would really make a difference.  I would suggest to put the $ in a tuner and use the wire dipole with twinlead.

Howie, K9KM

-----Original Message-----
From: ilqso-bounces at mailman.qth.net [mailto:ilqso-bounces at mailman.qth.net] On Behalf Of Hank Greeb
Sent: Tuesday, October 24, 2006 10:22 AM
To: Illinois QSO Party
Subject: [ILQSO] "Best" all round portable antenna

I've been operating portable for some 40 or so years. When I was a youngster, we bought a camper trailer after the first kid arrived. We didn't have much money, but we wanted to travel. Those were in the daze of 25¢/gal (or less) gasoline, rentals at public campgrounds were around
$2 to $5/night, etc.

Almost every time we went out on a camping trip I took along the rig and "The Best all round antenna ever." I took about 30' of TV mast, four military surplus stakes, about 3' long and a bit over an inch in diameter, about 200' of rope, a bow and arrow, a fishing rod, reel, and line, some light string, and an antenna made from 65' of house wiring, from which I stripped two wires of 65' each (remember I didn't have money for nice stranded copper antenna wire) and made a 130' center fed dipole. For insulators I used plastic drainpipe fittings (again, very cheep, but very good insulators). I first used 300 ohm TV twin lead, because it was cheep, then granulated to 450 ohm transmitting twin lead. 
When trees were available, as they often were, I'd string a fishline over the trees, and then the string, and then the rope with the antenna attached. If the trees weren't 130' apart, I'd shorten the dipole. The tuner was a homemade balanced tuner, with manual taps, with which I was able to tune most anything. Later I found a small Johnson Matchbox and have been using it ever since...

The "best" camping experience was when we rented a cabin in Lake Hope State Park, Vinton County, Ohio, in 1977 or 78. We rented a cabin because the inlaws were visiting and it would have been very crowded in the camping trailer. Anyway, there were two trees, about 70' tall (optimum for an 80 metre dipole), but only 100 feet or so apart. I shortened the dipole to 65 feet by bending the ends toward each other, strung the antenna at about 65' level, and had the "best" signal reports I ever got from a portable setup.

More typically the trees have been 30 feet high, or so, and sometimes none available. When no trees are available, as was the case in the recent ILQP, I strung the 80 meter dipole at 32' as an inverted V, using the two ends of the dipole as guy wires, and a rope for the third guy. 
The included angle, looking from the top, was 120° - I didn't do the solid geometry to figure the actual included angle at the apex. This works quite well. In my daze as a traffic handler, I worked W6EOT on a TCC sked using this antenna from various camping sites in the eastern Untied States, and we never missed a sked.

Very low NVIS antenna are "okay" if you ain't got anything better, but ground absorption is very high. At a quarter wave up, antenna books tell me that much of the radiation will be going straight up. Absorption is still a problem, but generally when camping one doesn't have enough room for a good ground curtain. I haven't verified this with side by side experiments, but I do know that I always get "reasonable" reports during state QSO parties. The antenna is simple, foolproof, and easy to erect.

Try it, and you'll like it.

73 de n8xx Hg

p.s. My home antenna is a center fed dipole, for years it was 260 feet long, fed with 450Ω feedline, 60' in the center, and about 30' on the ends.
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