This is an answer to an off reflector conversation, relating to a "too long" electrical length over radials reducing performance. I am writing to the list since the subject and it's objection occur i
This is an answer to an off reflector conversation, relating to a "too long" electrical length over radials reducing performance. I am writing to the list since the subject and it's objection occur i
A 1/2 wave vertical over perfect ground has a theoretical gain of something like 2 or 3 dB over a 1/4 wave vertical. If we accept that the 1/2 wave vertical will have more losses, it is still that ca
Guy, I'm not saying that I understand this 100%, but I certainly do find it fascinating. I have a question, though. For quite some time, my understanding has been that by making a bottom-fed vertical
This is a lot mushier for buried radials, but the simple case for elevated radials is that the standing waves are set by the distance of the end of the radials from the radial feed, just like it is o
I see N6RK has addressed this statement in his response as well, but I would like to add that this kind of statement is often heard on the air, "That antenna of yours there is doing a FB job for you.
While I was in College I had a ½ wave 20 meter vertical on the top of a two story apartment building. Fed with a parallel tuned circuit taped at the 50 ohm point with about 20 or so 18 foot radials.
That's hard to imagine. A 1/2 wave vertical without any radials at all is only a few dB (2-6 depending on ground type and exact antenna shape) below that of a 1/4 wave vertical over totally perfect g
With commercial field strength meters being fairly available on the used market it would be one way to end the arguments with things that are purely speculative. Carl KM1H ___________________________
You're certainly right that comparative field strength measurements are the only good way to determine how well a given antenna is working, and I agree that one of these AM broadcast FSMs would be a
I share the frustration over the very minimal amount of data out there. However... Erection of a 260 foot vertical in a testing environment fairly well requires the facilities of a large antenna rang
Nonsense. For research purposes, just put up a balloon vertical on a calm day in some remote area. Set up a transmit source a mile away and compare received signal strength vs height. Temporarily rol
G'Day Topbanders, I am not sure how general a conclusions could be drawn from my experience, but I have a set up that is somewhat relevant to this thread, and have done some on the air testing with i
George, Are you familiar with the Franklyn antenna design? Some broadcasters swear by them and claim a 3 db increase over a 1/4 vertical radiator. Herb, KV4FZ ________________________________________
See http://www.fybush.com/sites/2005/site-051028.html For 1530 kHz, that's a PAIR of two vertical halfwaves in phase. 50 kW gives 3545.89 mV/m. Note the relative lack of neighbors, and therefore lack
Apologize for earlier half-done post. Spastic hit on send key. See http://www.fybush.com/sites/2005/site-051028.html for a Franklin and a nice article. For 1530 kHz, that's a *pair* of two vertical h
George, Some designs have been able to reduce the over all height of the Franklin by folding out or back the high voltage top and bottom portions. The phasing coupler is placed at the center with the
I don't really know for sure. But from modeling it and the article, I suspect not. He only talks about lack of 50 kW capable low Z strapping down to a radial field. He doesn't specifically say *no* g
Using an accumulation of remote beacon network measurements is probably the most reliable, and the only sky-wave measurement available to us for real, unbiased measurements for ham testing of this so