Several years ago I installed 4 1/4 wave slopers around a 94 foot Rohn 45
guyed with Phillystran. Please be kind, remember this all took place before
resources like this reflector were available, and u were lucky if one other
guy in the area radio society even listened to 160, little lone trying to
transmit.
Suffice to say with all the feed points gathered at essentially a common
node--pattern results were disastrous. What I had forgotten was the point
or area of max radiation was indeed elevated quite nicely (compared to a
base loaded vertical), but every antenna was in virtually the same
spot--there was no separation--as in a 4 square, or tricorner vertical
array. So no matter which antenna was active--the feed point had not
moved--hence, no discernable pattern (even on the rare occasions I could
get one of the legs to load.
Perhaps someone else found a way to make 1/4 wave slopers on 160 work off a
single tower. If not at least this may give u some options to think about.
If u must abandon the inverted L and the 75 foot tower is ur main support
structure, I would consider going to a separate guyed vertical for the
transmit antenna. Unless u can afford one of those beautiful Titanex units,
I believe u'll have to homebrew at least part of it. (I would consider
integrating the MFJ 1792 as a starting base then top loading it...number of
options). Alf Sommer, of Sommer Antennas makes a model T-50 which is an
even better option...but more money. Here is the T-50 to give u some ideas:
<http://www.sommerantennas.com/t-50.html>. Once u have reviewed all these
and decide whether u really want to spend $500 plus on a transmit setup, I
would reconsider the major asset u mention in the first line of ur post--->
A nicely toploaded 75 foot vertical!
By the way I'm assuming u have already purchased a copy of ON4UN's book
"Low Band DXing". A reread of transmitting systems in there is always
worthwhile. WITH UR SETUP SHUNTFEEDING THE TOWER WOULD BE MY FIRST CHOICE.
It's cheap, and it gives u a starting system to compare any other
installations to.
73 es gud luck de Frank KB8XU
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