Home |
Search |
Today's Posts |
#31
|
|||
|
|||
Walt, W2DU PS--don't you find it ironic that when radiation measurements are taken in the far field the measured power already relates directly to the power delivered to the radiator? Then if Hart's version radiates more power than the standard radiator, where does his extra power come from. Looks like he's invented a new version of the perpetual motion machine. After all, it's patented, isn't it? So it's gotta' work. That's nothing, have you seen : "Antenna faster than light?" Saddly, patent laws were screwed up few years back, looks like patent office is rubber stamping applications as they come. Then there is a bunch of "ham extremists" trying to apply DC laws to loading coils, ingnoring reality, parroting what they learned in the DC class. Good thing itsa ju's a hobby. Yuri, K3BU.us |
#32
|
|||
|
|||
Eike Lantzsch, ZP6CGE wrote:
Reg Edwards wrote: There is an antenna with dimensions as small as 1 / 70th ( 1.43 percent) of a wavelength which has a radiating efficiency as high as 98.0 percent. It is a vertical copper tube, 1 metre high (39.4 inches), 25.4 mm (1 inch) in diameter, operating at 7 MHz. It is only 0.86 dB worse than absolute perfection, equivalent to a loss of only 1 / 70th of an S-unit. It is more efficient than a very high half-wave resonant dipole, using 14 awg wire, at the same frequency. And uses a far smaller amount of expensive copper. Has anybody ever applied for a patent for such an antenna which has such an outstanding performance? And did the Patent Examiner raise his eyebrows at the claim? ---- Reg. I don't know of any patents, but these "wonder antennas" are so "efficient" because they use the feedline as a radiator. The feedline is just terminated with a huge capacity. There is no magic to this - it is just bad engineering. Good morning RFI! Kind regards, Eike It's theoretically possible to make small, highly efficient antennas, but since the radiation resistance of such antennas is low as well as the loss resistance, the Q is high and the bandwidth stinks. 73, Tom Donaly, KA6RUH |
#33
|
|||
|
|||
Tom Donaly wrote:
It's theoretically possible to make small, highly efficient antennas, but since the radiation resistance of such antennas is low as well as the loss resistance, the Q is high and the bandwidth stinks. 73, Tom Donaly, KA6RUH It also becomes difficult to transfer power to them without incurring signficant loss in the matching network components. Roy Lewallen, W7EL |
#34
|
|||
|
|||
"Fractenna"
Radiating feedline is not bad engineering. Its one of many design options, applicable in some circumstances. Yeah, like BPL !!!!! ROTFLMAO. Gotcha! |
#36
|
|||
|
|||
There is not one shred of science in any of this - except the words they use to disguise the fraud. 73's Richard Clark, KB7QHC Thanks to OM Mario, 9A4DE, who called my attention to the following two sotes, I got the answer I was looking for. The sites a http://www.home.earthlink.net/~calvi...enna_test_repo rt_2.pdf |
#37
|
|||
|
|||
R
There is not one shred of science in any of this - except the words they use to disguise the fraud. 73's Richard Clark, KB7QHC Thanks to OM Mario, 9A4DE, I finally got the answers I was looking for: Visit these sites: 1) http://www.home.earthlink.net/~calvi...enna_test_repo rt.pdf 2) http://www.home.earthlink.net/~calvi...enna_test_repo rt_2.pdf Thanks everybody for taking part in the discussion. My dilemmas have been solved: - practically: I am not going to build the EH antenna. - theoretically: The EH antenna behaves exactly according to the existing classical antenna theory. Bozidar, 9a2hl |
#39
|
|||
|
|||
Richard Clark wrote:
There is not one shred of science in any of this - except the words they use to disguise the fraud. 73's Richard Clark, KB7QHC Sorry, the previous message went out only partially. Here is the whole: Thanks to OM Mario, 9A4DE I finally got the answers I was looking for. Visit these two sites: 1) http://www.home.earthlink.net/~calvi...enna_test_repo rt.pdf 2) http://www.home.earthlink.net/~calvi...enna_test_repo rt_2.pdf That means: - practically: I am not going to build the EH antenna; - theoreticallay: The EH antenna behaves exactly according to the classical antenna theory. Thanks everyone for taking part in the discusson. Bozidar, 9a2hl |
#40
|
|||
|
|||
On Tue, 19 Oct 2004 21:22:02 +0200, (Bozidar
Pasaric) wrote: Richard Clark wrote: There is not one shred of science in any of this - except the words they use to disguise the fraud. 73's Richard Clark, KB7QHC Sorry, the previous message went out only partially. Here is the whole: Thanks to OM Mario, 9A4DE I finally got the answers I was looking for. Visit these two sites: 1) http://www.home.earthlink.net/~calvi...enna_test_repo rt.pdf 2) http://www.home.earthlink.net/~calvi...enna_test_repo rt_2.pdf That means: - practically: I am not going to build the EH antenna; - theoreticallay: The EH antenna behaves exactly according to the classical antenna theory. Thanks everyone for taking part in the discusson. Bozidar, 9a2hl Hello, Bozidar, There seems to be a problem with the URL you posed above. I get the error msg 'page not available'. Can you fix the URL so we can see the quote? Walt, W2DU |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Inverted ground plane antenna: compared with normal GP and low dipole. | Antenna | |||
Mobile Ant L match ? | Antenna | |||
Poor quality low + High TV channels? How much dB in Preamp? | Antenna | |||
QST Article: An Easy to Build, Dual-Band Collinear Antenna | Antenna |