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Message: [QUOTE="Piggie, post: 45675, member: 2941"]I say, ham radio only accented my understanding of antennas. It has grown since those days also.Here is what bothers me. You are taking true things about antennas and extrapolating them beyond their normal usefulness.Mismatches in SWR on receive to me also are WAY over played. I already did a thread post about how even a 3:1 which would fry some transmitter at full power is only about a db of loss on receive. Not even noticeable even in analog reception of TV, AM, FM. With a good receiver you might tell the difference in CW and SSB. So I am not arguing that a non perfectly matched system won't receive.  Heck I have a 3 element yagi up now on the test jig that picks up all the Gainesville UHF at 25 to 37 miles away. It has to be grossly mismatched. But in this example of my 3 element the difference between the way I see it and you is you might say "see it works at UHF too".  I say the UHF signals are strong enough they are being picked up by the high band elements. After all the driven element on the thing is just a dipole that is a 3/4 wave on each side of the dipole that is know to resonant around 100 plus ohms.But I say when you start talking about antennas that are subharmonics of a 1/4 dipole, you either are matching it even to some degree to the feedline or the signal is just strong enough it works. Are those 8 inch elements for FM more than likely have a matching network. One of the most popular CB antenna was the base loaded 1/4 wave. They were only about 30 to 40 inches long, where as a full wave was 108 or so. They worked. Why? they had a matching network.I can match a paper clip to a TV with the right matching network.  I once lived on a dairy and could not put up anything tall, but their was a mile or more of fence.  I hooked up the center of some RG8 to the fence and grounded the shield to a rod.  Then went along the fence for several hundred feet in each direction and boned sections together. I didn't do anything on the higher bands but I could talk to all the local nets on 3.9 MHz.  I even had some use of 7 MHz.  That fence was tuned to who the heck knows what.  I made the fence resonant with a tuner. Look I understand your points, about things working that you would not think would work. Coupling between elements that at first you would not presume would happen.  But I guess it's the way you are saying that to me dilutes the entire discipline of talking about antennas.  I don't want to become the strict only if in a book like some of the AVS discussions but I don't want to see things that might mislead someone that knows little or a novice to think, why even measure a dipole? Just take 2 pieces of wire and hook them to a coax and you have an antenna.  Where in fact it is an antenna and feedline, it moves to far away from keeping some since of the facts.  If you want to use random wire for an antenna your reception will be greatly improved if it's even closely matched to the feedline. If you take many of the classic TV antennas and do models on them like that guy does at ham radio web site, you find the can range from 90 to 500 ohms across the channels they are advertised to work. And since they are classics we all know those same antennas work well.   So I am not talking about mismatches that small. I am also biased with my physics and math background.  If we want to propose something new that works such as an 1/8 wave dipole working well without a matching network, there needs to be some proof to the postulate.[/QUOTE]

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