Hi Jan,
I don't have any ground plane system installed with the E-H, and although I
did not check what you suggested (short-circuit the end of the feedline, and
just use that), I did a near-field probe with Tx key-down at 100W output,
using the diode detector and pickup coil on my Millen GDO, and it did appear
most of the radiation was coming from the antenna and not the feedline;
however, that wasn't terribly scientific.
Again, I'm not sure what the fuss is about with the E-H because when one
switches to any reasonable antenna instead, as I can do with my 5-port
antenna switch having four other options, everything blows away the E-H by
quite a margin; still, the E-H makes contacts on the other side of the
world, as evidenced by a 3B8 contact made on Sunday using it -- that's just
about as far away from Los Angeles as anybody can be (11,000 miles).
Which reinforces (once again) my conclusion that it's impossible to judge an
antenna by the DX it works, and only possible to judge it against other
known standards.
73 & thanks for your thoughts!
Steve, WB2WIK/6
> Hello Steve,
>
> I have done some detailed paper and simulation studies of the EH antenna
> and the antenna itself is very much bogus (an extremely small radiator
> excited in a mixed short vertical-short dipole mode), but as the inventors
> state in their messy documentation "The EH antenna needs a good ground"
> and
> accordingly most of the flimsy radiation from the EH comes from feeder
> radiation - the antenna is intentionally made unbalanced wrt ground. The
> EH
> antenna is a "scam" - you could make a scam test just by shortcircuiting
> the antenna terminals, but keep the feeder coax in position and then
> transmit - I am sure you could raise som good DX that way also. The EH
> antenna is a nice looking thing, but you could replace it with your
> bicycle
> or Granny´s candle candelabra without much difference. Look at a "folded
> monopole" made from a shortcircuited coax ("antenna" length = 4
> millimeters) - works well with a good ground or counterpoise network!
>
> By the way - have you seen that a variation of the EH-antenna also is sold
> as a protection device for "geopatic stress" - it catches evil "dark"
> radiation from space, reverses the phase 180 degrees and sends it back to
> where it came from. I saw a price of $989:- for such a device at an
> Internet site - some people beg to be fooled - hi.
>
> 73 & keep trying JAN/SM0AQW
>
>
> ----- Original Message -----
> From: "Steve Katz" <stevek@jmr.com>
> To: "'Bob Wanderer'" <aa0cy@VRINTER.NET>; <towertalk@contesting.com>
> Sent: Tuesday, October 15, 2002 12:24 AM
> Subject: RE: [Towertalk] choices
>
>
> >
> > I'm experimenting with an "E-H" antenna right now at home. It's 20-30
> dB
> > down from a full-sized vertical, but I make contacts easily with it, and
> > 9J2CA came back to me first call in a small pileup...which makes me
> wonder
> > not how well my antenna was working, but how lousy others' must have
> > been....
> >
> > WB2WIK/6
> >
> >
>
>
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