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[TowerTalk] Need Inverted L advice

To: <towertalk@contesting.com>
Subject: [TowerTalk] Need Inverted L advice
From: neader@QTH.com (Scott Neader KA9FOX)
Date: Wed, 02 Dec 1998 04:12:33 -0600
I have a small city lot with a single 72 foot self supporting tower.  I
would like to get on 160m mainly for domestic contests, but also to play
with some DXing.

I've decided that an Inverted L would be the way to go (but comments on
this decision are appreciated).

I have a metallic support already in place at the 68 foot level.  So, I can
go up the side of the tower 68 feet or so, then attach (non-conductive
material) to the metal support and then I can go out about 75 feet to a 40
foot tall tree.

I have drawn this out (don't laugh at my art!) at:

http://www.qth.com/ka9fox/plot-L.gif

If you don't know, I am a proud appliance operator and will be able to
apply for QCAO status just 6 years!  My questions are:

1) How long should the 'horizontal' part of the Inverted L be?

2) Because the horizontal part slopes down from about 68 ft to about 40
foot, I hear I will have some 'cancellations' -- how severe will that be?

3) For the radial system, can I attach the shield of the coax directly to
my tower grounding system?  (it is VERY extensive - 8 runs of 20-40 feet
each using #2 wire, with each run having 2 to 4 ground rods) or do I have
to use a separate radial system?  NOTE:  as you'll see in the drawing, the
tower ground system fans out away from the tower in the OPPOSITE direction
that the 160L will run, as I have no room to put any tower or antenna
ground radials in the direction of the Inverted L.  Is that a problem?

4) If I have to use separate radials for this antenna:
   a) I don't have much room -- the longest run from tower to fence is 40ft.
   b) I have a young child that plays in the backyard.  How can I keep him
      from tripping on radials while not spending time burying copper?

5) I have a big variable capacitor that says the following on it:
      NATIONAL CO. INC.
      TYPE TML
      VOLTS 7.5M
      200D MMF
   If I need a capacitor at the base, will this work?

6) The wire I bought for this antenna is 150 feet of #14 stranded wire with
a green insulation on it.  Will green wire as good as the white wire I have
for my 80m inverted vee? :-)

7) Will there be any 'hot points' on this antenna either at the base (child
hazard) or in the tree (fire hazard) that I should be aware of?

Thanks in advance for the assistance!

73 - Scott KA9FOX
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