[Elecraft] EH Antenna Patent

Wed Feb 26 21:05:05 2003

On the other hand, Larry, even though the antenna is connected directly to
the 817, who is to say whether the antenna adjustment was tuning the
MiracleWhip or the 817 case to be the "radiator" or vice versa? Clearly the
entire "system" radiates even though we tend to restrict our view of the
radiation as coming from the component we term "antenna."

Roy Lewallen brought up this point once while we were discussing the
mounting and tuning of a whip on my large motorhome. He asked how I could be
sure whether my antenna adjustments were actually tuning the antenna with
the motorhome ( and capacitively coupled Earth around it) as a reference
ground or were the antenna adjustments actually tuning the motorhome chassis
to be a more effective radiator?

Another glass half-full or half-empty sort of thing, I suppose . . .

73/72, George
Amateur Radio W5YR -  the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"

-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Larry Weaver
Sent: Wednesday, February 26, 2003 7:39 PM
To: Vic Rosenthal; [email protected]
Subject: Re: [Elecraft] EH Antenna Patent

At 08:06 AM 2/26/2003, you wrote:
>Larry Weaver wrote:
>
>I think the exaggerated claims for the e-h antenna and the Miracle Whip
come
>from the same source:  if a very short antenna is tested with a longish
>feedline
>without taking precautions to prevent feedline radiation (a choke balun),
then
>the feedline may accept and radiate more power than the antenna.  Obviously
a
>30-foot feedline in the right place can be an excellent 20 or 40 meter
>antenna.

The message that got sent was an earlier version. I must have been asleep.
:^) In the lost version, I took out specifically naming Miracle Whip
because it only represents one of many. I have no reason to knock Miracle
Whip; it is just an example.

Since I did, it attaches directly to the back of the FT817--no feedline. I
agree with you when there is a feedline involved. I picked the Miracle Whip
for comment because HF Pack had measurements with and without a ground.
Essentially, the MIracle Whip is the equivalent of the rubber duck on HTs
where adding a counterpoise also improves the radiated signal. The
arguments will go on because as several people have pointed out,
comparisons are so difficult to control-- particularly on HF. I think HF
Pack did one of the best jobs by using good, calibrated equipment and a
setup that seems to reduce variability.

Field strength is the best performance measure but is seldom available. The
web page for MIracle Whip, like others, states performance as "remarkable"
and refers to testimonials. Testimonials speak more about the miracle of HF
propagation than any antenna. I've made contacts hundreds of miles away on
160 meters using an 80 meter dipole fed with RG58 that, unbeknownst to me,
was laying on the ground.. Working any European country from the east coast
and Hawaii from the west coast on 10 meters is not necessarily remarkable
no matter what the antenna.

Ernest Hemingway said everyone needed a built-in, shock-resistant BS
detector. Until Elecraft comes up with a kit for one, becoming familiar
with antenna principles by reading the ARRL Antenna Handbook, L. Moxon's
book "HF Antennas for All Locations," and browsing W4RNL's
website   http://www.cebik.com/radio.html  especially the series done for
"Low Down" linked at the bottom of the page will help.

73...Larry N6TW

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