Fellow TT's,
My delima is this:I have raised my 50 ft tower to 85 ft so
I can stack 2 KT34XA's.I originally had 1 KT at 50 ft rotatable.
I fed it with 75 ohm catv.It worked great,good swr curves where
they should be.I now have this beam mounted to the side of the
now 85 ft tower at 50 ft.I have run a new piece of catv to feed
the
stacked beams when I get the 2nd one mounted at the top.I am
going to use a stackmatch fed with equal lengths of 8214 coax.
By the way,I have cut the new catv to 1/2 wave electrical length
so as to get a good match.I decided to hook up the beam that
is sidemounted on the tower to make sure it didnt get out of
tune by being bolted to the tower.I have 2 27 ft pieces of 8214
that I intended to use from each beam to the stackmatch.I used
one of these to hook up this beam directly to the catv.Lo and
behold,my swr was totally out of wack.I was thinking that maybe
this coax was bad because I have had it a while.I took the other
piece and tried that but got the same results.So, I took a full
50 ft
piece of 8214 and hooked it up and found that all became normal
once again.Can I assume that this length has now made things
where they are supposed to be because of lengths? Should I not
worry about the fact that I now have excessive lenghts of coax
that
I would assume having more loss in the system?My new piece
of catv is probably about 50-75 ft longer than it needs to be to
feed
the tower,but it had nulls right where I wanted them.Am I
defeating
the purpose of the hardline by using the longer than necessary
lengths?
If I leave things as they are,I will have a total length of 293
feet of
feedline to the beams.I would appreciate your comments,and I
am hoping that I havent just created a massive dummy load.It
seems
to be working well though.
Thanks,
Bob-WT9Q
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