Jim, I forgot to mention that 90 or 100 feet is plenty of separation for
a phased flag array made of two un-terminated flags mounted vertically
I made a cheap water drill to mount mine and PVC pipe goes into the
ground like butter and cements tight almost immediately. I droverr a 1
1/2 x 10-foot PVC pipe 5-feet into the ground and then a couopling and
another 10-foot section on top. That's enough to get the bottom wire of
the flag at about 4 feet from the ground and it works well. But as a
note, paint the top pipe black before you put it up to make it disappear
from view. White shows up pretty well. Black doesn't.//The bottom part
and the coupling is easy enough to reach to paint from the ground. /
/
If you wanted to you could terminate the bottom corner opposite the
feedpoint, either adjusting that and then making up a fixed resistor
pack or using a VACTROL to make it remote adjustable, but I find my
ability to move the null where I want it is great without the
termination and loss of bi-directionality and the additional 30 dB loss
with termination so you need a preamp at each loop. Unterminated you
don't need the preamp./
/
Rick Kunath, K9AO
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