Mike
This may not go out to the reflector (hove some problems with it !); but you
will see it.
I'm no expert on shunt feeding; but I would look in ON4UN's book, or even
the ARRL handbook would help you.
I assume you are referring to just a series 600pF variable capacitor, in
your previous experiences with inverted L's ? That will only be any good if
the antenna is greater than a quarter wave. So you could make it work for
80, but not 160.
I would approximate what you have as a 64' vertical, with a 15' capacity
hat, FWIW. If you do solve the gamma matching, it should work ok.
OR you could do one of the 2 things below :
1) use a halyard at the very top of the mast to hoist up an inverted L.
Even better if you can increase the free pole length at the top - you may be
able to pull it clear and fasten the "horizontal somewhere, that would still
allow the 6m array to turn ?
2) Get a fibre glass pole to insert in the top of your 16' pole; make a top
loading coil ( waste pipe is often good for this). I have done this at MD4K
to good effect; though probably a bit more ambitious than you had in mind.
Here; I used a 60' tower, with maybe 10-15ft of scaffold pole; and then used
a 30' fibre glass pole; and slid the top loading coil down the fibre pole..
I run the wire to the top; and run the wire off the bottom of the loading
coil to a convenient point just away from the tower. Since we don't have
too many shots at getting this right; if more inductance is needed, I insert
this at the base (I would prefer to put it at the top, of course!)
I am assuming that this tower tilts over ? !
73
Dave
G3NKC
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