On 10/27/2013 2:26 AM, Jim Thomson wrote:
Take one of these 89 ft crank ups....and run it from 26 ft nested..up to
89 ft extended..and it’s a real eye opener. I have a slight uphill
rise from N-S...all facing east. And slightly downhill.... from
N-S..all facing west. I need all the height I can get when pointed
at EU, AF, SA, etc.
Right, but you said flat land. I have similar topography here to the
I am lucky enough to have a 106 foot crankup, and BTW, I'm on flat land.
At the time I acquired the crankup, the answer to "why 106 ft?" was
"because I could" rather than any particular "engineering"
justification. Recently, I set up a 40 foot tower 100 feet away from
the crankup with a SteppIR Yagi on top. The crankup also has a SteppIR
Yagi. This setup allows me to do direct A/B comparisons in real time.
With the tower cranked down to 40 ft, the two Yagi's performed the same,
after accounting for slightly higher gain on the larger one.
With the tower cranked up, the increase in signals on a calibrated S
meter was often amazing, up to 10 or 15 dB, especially on long haul
DX. There were conditions like noon on 20 meters to the east coast
where the 40 ft high Yagi was equal to the high one. I haven't observed
any cases where the 40 ft high Yagi was better, but I could believe that
could happen occasionally. These tests were done on 20 through 10
meters.
Like you say, a real eye opener.
I purchased the tower from W6BH (recently a SK) who replaced it with ...
an even higher tower, of course.
Rick N6RK
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