My POTA Setup

Discovered Parks On The Air earlier this year as a hunter and with the purchase of a camper in the spring. I began to plan a portable antenna setup to operate with in conjunction with weekend getaways and longer vacation duration trips. 

Initially I experimented with both a Buddipole and a remote tuned inverted L using an painters pole and a 2 inch receiver hitch bracket I fabricated. With 40m being the best overall band given current propagation, I set up the Buddi as a 40m vertical with 4 radials. Ultimately the Buddipole with a base load was not efficient enough and took to much time to setup. The inverted V while more efficient, I was looking for a quicker setup and the highest practical radiation efficiency. 

Based largely on the performance of POTA activators I ordered a SpiderBeam 12m (40ft) collapsible fiberglass pole. And began to fabricate a new trailer hitch mount to support the pole while continuing to use the remote tuner, a SGC-230 which tuned the inverted L.

A 12 Inch Harbor Freight extension into which is an adapter I fabricated.
I use wing nuts for the vertical element and well as the radials.
The vertical radiator is a 37 foot piece of #18 standed which ties to an eye on the smallest fiberglass element. Takes a couple of minutes to extend the sections which are friction fit.
Setting up the station at Mount Magazine Campground

The vertical element is 37 feet of #18 stranded black jacked copper. There are 5 radials 30 feet in length made of #14 Flexweave. I have soldered on ring connectors on the vertical and the radials which makes for a quick hook up on the tuner.

The outcome has been fantastic I can setup in under 20 minutes with great performance on 20m to 80m.

During a recent 10 day trip I had time to read several antenna modelling books which have been on my reading list for some time. Having the time to model this setup I was able to confirm what I was seeing in practice. The antenna is efficient on 40m, has gain on 20m and while it will work on 60m and 80m the efficiency has dropped off due to being to short. 

With 37 feet of available vertical space, one could run this setup with length adjustments on 40m without a tuner.
Reasonable far field departure angles below 20m and nice low angle for 20m with a little bit of gain.

Theory aside empirical data is needed to confirm the models, a perfect job for one of the digital modes supported by Pskreporter. In the 20m plot below notice the hole in the middle of the country? I was operating in Arkansas at the time and the lack of nearby coverage as a result of a low departure angle is quite evident.

20m FT8 Pskreporter report, notice the hole in the middle?

With a low departure angle <20 degrees DX should be within reach and is confirmed with a world view showing coverage into europe.

While not as efficient on 80m due to the overall length it is efficient enough for coast to coast coverage.

In closing for my operating style this setup works great, it is quick to setup and tear down and minus the tuner which I already had. Relatively inexpensive compared to the other station components and the costs to travel to activate. 

73, Jay

 

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