A Very Simple Antenna

#1
As one who has a fascination with antennas and is always looking to try something new, simple, cheap, or free. I've built and tested many simple antenna designs, from pop cans, and coat hangers, to well designed 4 bay bow tie antennas. While almost any wire can work as an antenna in strong signal areas most random wire antennas work very poorly, however with of few simple tools a bit of time, patients, and creativity one can construct a simple antenna that might work as good or better then the latest magic little HD antenna that one finds on the shelf of the local big box store often times priced from $20 to $60.
The first time proven design that comes to mind is the simple single bow tie antenna. While such a simple antenna has vanished from store shelves. No one collects enough money selling those, such a simple design doesn't offer the eye appeal to sell well, and everyone knows it's not digital, or HD. The designs used in the past were not optimized for todays UHF channels 14-51 they still work quite well as shown in this test.
Antennas, Antennas, On The Wall
While I'm not one who has learned to do antenna modeling in 4nec2. I have a great appreciation of those who have posted the results of their work in 4nec2 on the Internet for all to make use of. Some variations of the simple bow tie antenna optimized using computer modeling can work quite well for those living in good signal areas.
UHF Bowties - NO Reflector
The easiest one for me to build is the simple four whisker.
DSCF0227.jpg
Two pieces of 9 AWG wire about 21” inches long, three screws, a few salvaged scraps of PVC, and a balun. The one in the photo is built from 9 AWG aluminum which can create dissimilar metal problems in long term use. 10 AWG copper would be a good choice.
Out on the test mast 7' high the results were quite good. Solid reception of all signals in green, and yellow on the TV fool report from a simple little antenna built out of two bent wires.
TV Fool

Steve
 

dkreichen1968

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#2
A few years ago I went out to Black Forest to help a coworker with her roof top TV antenna. She wasn't getting reception. To get a base line of reception I made an antenna out of a clothes hanger. It got most of the local stations, so I knew the reception problems weren't a lack of signal. Ultimately I found the problem to be a shorted out cable between the wall and the TV.
 
#3
I've often wondered how many missing channel complaints are due to excessively high SWR from poor connections. With digital signals you can selectively loose one channel that has a strong signal from high SWR on a feed line at that frequency.
I was not real clear on the dimensions used. The 21" of wire bent in the center makes each side about 10" with a 5 inch spread between tips. The center spacing at the feed points is 1.5" giving an over all width of 21.5". The center insulator is a piece of heated flattened PVC. While I have built antennas on wood I do not recommend using wood as in most cases it will degrade performance. The less contact with plastic the better. Some plastics may not be suitable for antenna use and could significantly degrade performance.
While the single bow tie I chose to post is a UHF antenna the strong VHF signals in my area were easily received. I am not one who ever recommends a UHF antenna for reception of VHF signals, and with some UHF antennas it will not work. I have built UHF antennas that will not receive even strong VHF signals.
With a bit of creativity a simple single bow tie antenna could be built for permanent out door use. One company has marketed an antenna that appears to be nothing more than a single bow tie enclosed in a plastic housing at a very high price. With the use of a mast mount pre-amp you could significantly reduce the feed line loss caused by high SWR on VHF, and possibly even improve the UHF reception by using an amplifier with a lower noise figure then the tuner in use, and eliminating feed line loss.
Steve
 
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