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[QUOTE=&quot;RF Steve, post: 141764, member: 18630&quot;]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&quot; of wire bent in the center makes each side about 10&quot; with a 5 inch spread between tips. The center spacing at the feed points is 1.5&quot; giving an over all width of 21.5&quot;. 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[/QUOTE]

[QUOTE="RF Steve, post: 141764, member: 18630"]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[/QUOTE]

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