My ongoing issues with my shorty tower continue, but suffice to say I have
tried every configuration on my short tower to get it
to work "well" on 160m, only to see other compromise antennas to work as
well, or better.
I don't wish to rehash all what I've done and bore the list once again, but
I do have a specific question related to a base insulator itself.
My Delhi self supporting towers legs are in a large hole, and as best as I
can recall, are sitting on 3 separate large rocks and/or bricks (obviously
at the bottom of the hole). IIRC, I then poured 3-4 cubic meters of
concrete in the hole, so the concrete block measures ROUGHLY 8'x8'x4' deep.
(it's not symmetrical by any means) Concrete surrounds the legs and it did
not move off the rocks when it was poured. (I had it guy wired into place)
I have found that feeding my tower "AS IF" it's insulated from ground has
proved to work the best vs. all the other configurations I have tried. (ie:
shunt feed, ohmega match, delta feed ad naseum.) (Performance-wise.)
With all the configurations I have tried I can always get a 1:1 SWR, but
performance is poor.
Performance is still poor, however this configuration is NOT QUITE as poor.
(hi)
So.....how much signal am I losing as my insulator (huge block of concrete)
is not a perfect insulator?
Would I need a megger to measure ground conductance or ??
=========================================================================
Problem is, a simple Alpha Delta DX-A twin sloper @ 30' always performs as
well or better than the tower !
tower=48' Self Supporting Delhi, then 16' mast, @ tower top<bottom of mast>=
30' boom 6m yagi & at top of mast=identical yagi
I have about 33, 1/4WL radials in a more-or-less symmetrical pattern
radiating out from the base of tower.
Thanks
Mike VE9AA
Mike, Coreen & Corey Smith
699 Rte 616 Keswick Ridge
NB
Canada
E6L 1T1
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