Sunday, June 5, 2016

Testing Field Day Antennas

I am offering a couple of new antennas for our club field day. Of course, it is best to test them before the event to know at least that they tune up. I was able to do that on Saturday.

Feedpoint for 160 meter loop
The first is a dream antenna. That would be a 160 meter full wave loop. Chameleon Antennas has an 80 meter Skyloop and Carl will fix you up with a 160 meter version.  It is 500 feet long and it has a 4 to 1 balun. We deployed it on an open field. It would not have been possible with out the fiberglass poles Mike KM4ELJ provided. They are 28 feet tall and are fairly rigid at the top. They are designed for flags. Mike  has ten of them and we used seven. We setup the supports 80 feet from a central point. This approximates a circle. It did not take long to deploy. But one hitch was that a boater had parked a truck on our wire when we were not looking. We are near a boat ramp. The boater had left. Fortunately Mike had a floor jack in his truck and jacked up the truck and freed our wire. The antenna SWR was about 3 to 1 on 160, less that 2 to1 on 80. A bit high on 40 and less that 1.5 to 1 on 20. We will be using a short coax run and a tuner. We made some 80 meter contacts with good reports. The layout won't be as easy at our Field Day location. We will be working around parking lots and ponds on the property. Thanks to Mike KM4ELJ and Jim K4LIX for help with the setup.

One of the 28 foot flag poles


The second antenna was a 130 foot doublet I got from DX Engineering. I followed their instructions and cut a 1/8 wave section of 300 ohm feedline adjusted for velocity factor, That was about 31 feet. I have an Icom AH-4 tuner which I like as it integrates well with my Icom 7100. It can feed balanced line antenna like the doublet. Deploying this antenna is fairly easy. I use a mast made of camo poles with a tripod at the center and four Jackite fiberglass poles to support the legs. It tuned on 80 through 10. I skipped around and made contacts on 80, 40 and 20. I think we are good.

130 foot doublet
Icom 7100 and the Icom AH-4 Tuner
Our club also has a NA4RR Hex Beam also for field day. It will be on a portable tower. Of course we may have even more antennas but the loop, doublet and hexbeam are a good combo for three transmitters. The Panama City ARC plans to be 3F from the Bay County EOC Our callsign will be W4B. The EOC has indoor air conditioned space but we will also have a battery powered outdoor rig as well. If you like antennas Field Day is a good time to try them out.

Suzy supervised our testing.