At 09:06 AM 1/19/98 -0800, k6ct wrote:
>I have a 2 element vertical array for 80m. I have received conflicting
>information as to how best to phase the two so I can go in either direction.
>The verticals are spaced 65 ft apart, are elevated and each have elevated
>radials. Here are the two methods that have been proposed:
>1. Current fed- using a relay, switching with a 71 degree phase line so that
>the lagging element is the direction of power distribution.
>2. Parasitic excitation, using 3/8 wave between each vertical and the switch
>box to the shack.
>
>What are the pros and cons of each and I would like to hear from those of
>you that use these two different feed methods as to efficiency and how well
>the work.
>73 Tom
>
>
Tom, I am not a pro by any means but I too phased 2 verticals with
outstanding
results using the 71 degree phase line. This actually has 84 degree lines
going to each vertical with 213 coax to the relay switch box and that has
a 71 degree delay line that it switches. ON4UN's lowband dxing book on page
11-8 shows this clearly and it DOES work great. It worked so well that I
decided to upgrade to a homebrew 4-square which works even better.
My swr on the 2 verticals was 1.2:1 across the the bottom 200 khz of the
band. (40 meters) For me, 80 meters is next spring. Good luck and
73......Steve....NW9G
P.S. my switch box I used on the 2 verticals was the ameritron remote
box. It had 3 empty slots on it but it was handy at the time.
Now, I have 12 volt relays with 2 conductor thermostat wire and it handles
my Titan amp at full power.
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