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Old July 11th 05, 11:30 AM
Reg Edwards
 
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Trev,
Performance is no better and no worse than what can be expected from
any other sort of antenna of about the same physical size and the same
length of feedline. Try it and see.

I once worked 3 miles on SSB, on 160m, in broad daylight, with about
10 milliwatts, on 8 feet of wire lying on the ground, thrown out of a
downstairs window. The ground connection was via 10 feet of wire from
a domestic gas pipe. But I don't brag about it. The credit all goes
to Clerk Maxwell.

As Clerk implied, any bloody thing works.
----
Reg.

====================================
..
"Trevor Day" wrote in message
...
In message , Walter Maxwell
writes
snip
Just try to imagine what you bloody 'ole Brits could have

accomplished
around 1200 if you'd only had the tremendously high voltages

achieved in the
near field of a CFA antenna to hurl at the enemy.

Walt


Excuse me for 'jumping in' here, it was difficult trying to locate a

bit
of the thread that referred to the current title (CFA) I would

like to
ask you learned chaps a question about the 'EH' antenna which I
appreciate is not the same as the CFA but its near enough for me:-)

I have built a couple of these and used them on 40m. Performance

hasn't
been brilliant but they have worked and I was reasonably satisfied

with
the contacts achieved considering the fact I used a barefoot K2 at
around 10 watts o/p and the antenna was sat on the shack bench

connected
to the K2 by a 1 metre BNC to BNC cable laid across the bench. (I

only
mention this last to try and forestall the inevitable comment that

the
feeder does all the work)

All of this was done out of interest just to see if the antenna

worked
at all, as my gut reaction was, and still is, sceptical regarding

the
claims of its method of operation. I am not a mathematician, so the
various lengthy discussions regarding Maxwell's equations et al pass

me
by; I am more interested in the practical aspects of this rather

than
the theory. My question refers to the SWR bandwidth achieved using

this
system. For an electrically very short antenna of this type I

expected
something extremely sharp at resonance, perhaps in the order of 5 or

10
KHz between the 2:1 SWR points. In practice, the 2:1 SWR points are
some 100 KHz or so apart. When fed with 100 watts from an IC706,

the
antenna itself does not get warm and neither does the short feeder

so it
doesn't appear to be acting as a dummy load. Can someone satisfy

my
curiosity and tell me (drawing comparisons with springs and dampers

if
need be:-) how this is achieved.

Thanks,
Trev G3ZYY

--
Trevor Day
UKSMG #217
www.uksmg.org