Friday, September 15, 2006

Antennas for travel: fishing poles

In a previous post I said that I would try to explain why a man that doesn't fish needs so many fishing poles. This was part of a series of posts that I had made called Antennas for Travel that I ran in July. I did not expect so much time to have passed between elements of this thread. Sorry!
Lightweight vertical antennas are an excellent alternative to bringing yagis and dipoles on your trip. You can certainly make vertical antennas out of aluminum pipe, and many are made that way, but the other way to create a light duty vertical is to use a fishing pole or other mast to hold up a wire. The Black Widow fishing pole shown below is an excellent backbone for such an antenna. It weighs next to nothing and easily holds up a radiator long enough to cover 20m without loading, and down to 40m with a little bit of coil.

While on my recent trip to St. John I used one of these beauties to hold up my 40/15m radiator, a 33 foot wire suspended from the top of the pole (which was affixed to a corner of the roof) leading down to the ground where it was attached to the feed line. I made many of my contacts during the ARRL DX contest this March with this very simple, and very lightweight antenna.
At Atlanticon, the New Jersey QRP Club's yearly conference, I ran into Ed Breneiser (WA3WSJ) who has an interesting add-on for these poles including a loading coil that you can see here. While I don't own his coil, it is an interesting idea and there are plenty of folks in the QRP community who use it successfully.
Ed and Ron Polityka (WB3AAL) are involved in a group called the Polar Bears who carry lightweight QRP transceivers and very lightweight antennas such as these Black Widow specials when they camp on the Appalachian Trail. These guys have been very successful operating from Pulpit Rock near Hamburg, Pennsylvania with little more than fishing poles, wires, and QRP.
If you wish to get something a little longer, try the DK9SQ 33-foot collapsible mast available from Kanga and other places. I use this mast on St. John as well and found it very strong. Like the 20 foot black widow, I mounted this on the roof of the guest cottage and hung my 66 foot wire for 80m from the top, sloping down to the ground. Both this 33 foot mast and the 20 foot Black Widow collapse to under 48 inches so they both fit into a hard-sided golf bag for easy travel.
You might also wish to procure some very lightweight and strong wire to go with these poles. I can highly recommend the number 534 wire from The Wire Man. It has the following description:
'Invisible' Toughcoat 'Silky' 26 AWG, 19 strand 40% copper-clad steel (OD 0.020") with the same jacket as 531 (Nominal OD, 0.050" including 0.015" jacket, but super small for that 'low profile' antenna or pocket 'weekender' long wire. Weighs less than one pound per 1000 feet! Not recommended for 160 meters.

This stuff really is tough, very strong, and it weighs next to nothing. I've used it for the radiators and radials on St. John and have cut a set of radials for my Buddistick that are now packed into the bag with the antenna. I've attached spade terminals (Gardner Bender Model 10-143M) to the ends of these radials and have a mating female bundle to accept them at the feed point of the antenna for quick deployment.
Verticals, especially using this fishing pole or fiberglass mast approach, are a very effective way to get a whole lot of antenna for very little money and very little weight. I've had good luck with this approach, even when I've been lazy about putting out radials. Down on St. John, both verticals (the 33 foot wire and the 66 foot wire) had one radial. I could have done more, but I wanted to see what the minimal setup would get me. I was pleasantly surprised.

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