Hi Nat!
There IS quite a distance difference between W3LPL and K3LR, with LPL being
much closer to Europe than LR. LR enjoys a distance advantage to Japan over
LPL.
As K8DX pointed out, the 4 element OWA WA3FET design that I use has wide VSWR
bandwidth (7.0 to 7.3 MHz at less than 1.3 to 1) and is very easy to feed
(direct 50 ohms unbalanced with a current a choke). The gain and pattern of
this 4 element full size beam (380 pounds) is almost exactly the same as LPL's
3 element design as both designs are on 50 ft booms. I have insulated all of
the elements with G10 Fiberglass plates as suggested by W3LPL in his previous
postings.
We actually changed the design a few years ago and now the lower beam is at 118
feet. This closer spacing optimized the in phase stacking pattern which is the
key to working many stations on 40 meters. The lower beam is on a ring rotor at
LR and I believe the LPL lower antenna is fixed on Europe.
I use a current feed network when feeding in phase. A custom remote antenna
switch allows the operator to choose 4 antenna combinations. 190' antenna only,
118' antenna only, 190' and 118' in phase and 190' and 118' out of phase.
KC1XX's 40 meter antenna is the same WA3FET OWA design as used at K3LR.
Last summer I built 4 element 40 meter WA3FET OWA antennas for K4JA (2), NO8D
(3), K8AZ (1) and K9NS (K9HMB) (2).
A quick check of past 40 meter contest results shows that the signal strengths
of all of the multi multi 40 meter stations is so close that final contest QSO
numbers really come down to the operators and the propagation.
You can see pictures of the K3LR 40 meter beams at http://www.k3lr.net
73,
Tim K3LR
Nat Heatwole wrote:
> Sorry for the mistake, I was thinking of KC1XX not K3LR when I wrote that
> K3LR was a little closer to EU. There really is not much difference in
> distance from EU between W3LPL and K3LR. Again sorry for the mistake, I got
> to get my M/M's straight!
>
> 73, Nat, WZ3AR
> <heatwole@clark.net>
> Damascus, Maryland
>
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