Unusual Antennas
Others were thrown up in trees, or flown from kites or balloons. Some were made use of existing metallic structures loaded up on different frequencies.
I thought it might be interesting to pass on to you a description of some of these strange antennas. If you have used another type of unusual antenna, why don’t you write it up and send it in? It does not have to be anything fancy, just a description of the antenna and how it worked or didn’t work. If we get enough of your experiences, we will put them together into an article with due credit to all who have contributed.
Bushtenna
At the heart of most of these creative antennas is a single wire, sometimes more than one strung, draped or thrown across an object for support. A good example was the bush antenna. One of the hams that I knew simply strung a length of insulated wire through the tops of some evergreen bushes that surrounded his house and got on the air. He did get out rather well on the higher bands 20 to 10 but not too well on the lower bands. This was what he used until he could find a way to get up a trap dipole that could not be seen from the street.
Treetenna
Another ham threw a length of wire up a tree and worked it against ground. The only problem was, on some bands, the end of the antenna was at a high potential and it finally arced and set fire to the top of the tree one winter day. No one knew the top of the tree was dead, until it caught fire. Too much power was the ultimate demise of this antenna, along with the tree.
Balloontenna
Another ham threw a length of wire up a tree and worked it against ground. The only problem was, on some bands, the end of the antenna was at a high potential and it finally arced and set fire to the top of the tree one winter day. No one knew the top of the tree was dead, until it caught fire. Too much power was the ultimate demise of this antenna, along with the tree.
Kitetenna
One Ham I know used a parasail kite to pull up a half-wave vertical antenna on 160. It is at a slope due to the wind and exhibits some directional characteristics. He reported excellent results, some of which I monitored during the past winter. His signal was getting 40/9 reports from both coasts and somewhere up near the North Pole. I also heard several South American stations giving him similar reports. Operation was from a clear spot near the bay. But, flying a kite this high in a residential area is not a good idea, for many reasons and power lines is one of them. So by operating mobile he was able to do a very good job on 160. He also ran out four radials from the antenna connection point and grounded the very short ground line from the antenna coupler to both the ground rod and the radials.
Treetrunktenna
Another Ham wrapped a tree trunk with lamp cord from ground level to the top at 60 feet. He spaced the turns about two feet apart at the ground level and more or less the same as he got to the top. At the top, this Ham put the end of the wire into a small pill bottle full of RTV silastic to keep the end of the wire from arcing. This antenna worked well for him for a long time and was never noticed by anyone as the lamp cord color matched the tree trunk. Eventually, the wire had to be replaced because the insulation was beginning to fall apart. No comments on how the tree felt about this were ever heard.
Using vegetation for antenna supports is nothing new. Even the U.S. Army, at one time, experimented with using tree trunks as antennas. A device called a HEMAC was used to couple to the tree trunk.
Other Variations
One Ham had to take an extended stay from home, due to work, and he was staying in a large hotel. His wife was a Ham too and they maintained schedules nightly after he was able to match the large railing that ran around the balcony. This was on 40 meters and the distance covered was about 1,000 miles.
Rain gutters on homes have been used as antennas and work fine, as long as it doesn’t rain. Others have used the metal trim around their house eves. Another managed to use the aluminum window screen on his dorm room on 6 meters. And as far as dorms at college are concerned, the usual arrangements of coat hanger antennas have been exploited for years to allow operation on two meters and the other VHF frequencies.
One enterprising Ham built a small storage building, insulated it from ground and loaded it up on 160, 75 and 40 meters quite well. An antenna coupler was used at the building for maximum efficiency. Later on, this same Ham built an artificial tree out of aluminum and wire, then covered it with plastic leaves that had no wire inserts. This tree was a conical monopole in disguise and covered 30 meters through 15 meters if my memory serves me correct. Both of these antennas worked well.
Another temporary antenna, I personally saw in action, was a long wire that two Hams had managed to string up from the local 150 feet (46 m) high Harbor Bridge. This was a very long slanted vertical antenna put up for the 160-meter contest during winter. A 490T Collins automatic coupler tuned it and the reports received were 40 over 9 from everywhere in the Northern Hemisphere where contacts were made. That was some antenna. I will be willing to bet it was over 400 feet long (122 m). I also bet the metal bridge was acting as a capacity hat of some sort to further enhance the antenna’s efficiency.
Even Beer Cans?
The last antenna I am going to mention is the beer can vertical. This was first written up many years ago in CQ, I think. Yes, a Ham decided to solder a bunch of beer cans together to make a vertical antenna. This was done when the cans were all made of steel. Aluminum cans are not strong enough to allow any sort of large vertical to be made even if you could solder them together. While steel is not a very good radiator, if it is all you can manage, then go for it. The cans have to be cleaned thoroughly, and then good soldering flux and solder must be used on the connections between the cans. It did work, but should be guyed to minimize flexing in the wind.
Of course, these antennas all should be used with low power because most of them were used in situations for stealth mode operation. No doubt there are a lot more unusual antennas others have used and could tell us about.
Originally posted on the AntennaX Online Magazine by Richard Morrow, K5CNF
Last Updated : 24th April 2024