Hello all.
A few years ago when I put up my rotating tower here at the new QTH, I put
my trusty 205 Hygain at about 85 feet. This seemed like a good place
because it was right above my second guy ring and it seemed like a good
height. The antenna worked well and it has worked it's share of DX and
contests.
I had a 2 ele Quad on another tower at about 55 feet which was never
better, but often seemed as good except for the long haul stuff. No real
surprises.
About a year and a half ago, I got another 205 in a deal I couldn't pass
up. I figured I would mount it at 45 feet, just above the first guy ring,
where it might be useful for sweepstakes or something of the like.
I carefully cut all the lines and such to ensure the best phasing match I
could reasonably achieve. I didn't even bother to use any type of
switching. I just went thru the cables, 50 and 75 ohm, to a Tee and then
to the hard line to the shack.
Boy, was I ever surprised!!!
We finished it up just before the 96 WPX CW contest, so this was our first
chance to use it. The difference was immediately apparent. Europe was 10
db louder and my signal over there showed a like increase. This was
referenced to the stalwart 2 el Quad. Also, we were able to continue
running EU on 20 all afternoon with about a 25% increase in rate.
You could say a fluke on a given day, but it has been 20 months now and
this performance has been continually repeatable.
During the day, EU is looking for that high angle provided by the lower
antenna. It seems that we don't encounter as much signal fading as with
the single antenna.
People with stacked arrays who also use some type of switching arrangement
to individually select antennas or the whole stack, generally report that
most of the time they have both antennas selected. There may be times when
I wished I had control of the stack, but so far, I couldn't ask for
anything better.
Based upon this performance, over the summer I built a similar array for
15. During it's first testing in the 'heat of battle', it worked EU every
bit as well as the 20 stack.
I have to second what Tom has said about the lower antennas. Put your
'higher is better' ego aside and don't forget the low antenna. It
definitely has it's place.
73 de Steve, NJ4F
At 12:17 PM 12/13/97 -0600, T A RUSSELL wrote:
>Optimum Heights (once again!) de N4KG
>
>For FLAT ground, generally, you need a HIGH AND LOW antenna
>to cover ALL the angles that the ionosphere will support. I find that
>my 40 ft high antennas beat out the higher ones during daylight
>hours to Europe and Africa. Being close to the Caribbean, my
>HIGH antennas are often better than the low ones for the close-in DX
>since I must get there on a ONE HOP (low angle) mode. Guys further
>north probably can utilize the higher angle two hop mode.
>
>IMHO, everyone needs a tribander at 35 to 40 ft for daytime operation
>and a higher antenna to open/close the bands and for nighttime operation.
>
>If the ionosphere will support both low and high angles and the DX
>station is using a low antenna (high angle) what height do you think
>will produce the best signals to and from such an installation?
>
>Everyone I know who has BOTH high and low antennas with a flat
>foreground, observes the LOW antenna outperforming the high one
>during daylight hours on the high bands.
>
>de Tom N4KG
>
>--
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>Administrative requests: cq-contest-REQUEST@contesting.com
>
>
---------------------------------------------
Steve Bookout, NJ4F
Rapidan Data Systems
'DX4WIN...The way logging programs should be!'
Free demo at http://www.erols.com/pvander
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