Elevated radials work fine with a 4-square. I did that with wires hanging
around a 120' tower and it worked 'ok', with the verticals made out of rohn
25 with 8 raised radials at 10' with nothing in the middle it is much, much,
better. I would consider slightly shorter than 60' verticals on the ground
with a bit of base or top loading if you can get them away from the rotating
tower. I think the tower in the middle is worse than slight shortning to
keep them under 60' if necessary... I ran 48' verticals with base loading
for a few years and those were better than the raised wire verticals around
a 120' tower... of course then you need radials on the ground.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://wiki.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://k1ttt.net:7373
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Bill
via TowerTalk
Sent: Thursday, September 22, 2016 20:00
To: TOWERTALK@contesting.com
Subject: [TowerTalk] 4 square for 80
This will be my first foray into the world of 4 square xmit antennas.
Plans are to make the elements from wire, suspended from the tower by rope
at about 80 feet. Due to the slope of the ropes from the tower to the
ground, the elements might wind up a little short. Plans were to T-top them
running the wire parallel to the rope. The elements might be around 60 feet
so it would not be that hard to T top them to make up the extra length
needed for 1/4 wave.
I had planned to do the following: Have an elevated ground system a 1/4
wave radials running from the base of each vertical. Height of the system
would be 10 feet. Radial system would consist of 16 radials for each
vertical using the Comtek 4 square system to control it.
In talking with the guys at DX Engineering about the planned setup I was
given the not so good news.
First, I was told you CAN NOT use an elevated ground system with the 4
square.
Second, I was told the tower would interfere with the system. They said I
would have to cage the tower to make it "invisible" to the system. Caging
the tower is impossible since it is a rotating tower and the cage would wrap
on the stacks mounted on the tower.
Was he right about all of this?
I can not put up another tower due to tower restrictions (one tower
allowed), so the only way I can get enough height to suspend the wires is to
use the tower I have. The county thinks anything 60 feet high constitutes
another tower, so I can't make aluminum verticals. No trees around either
for supports.
I really am in a bind for 80 if all this is true. An inverted Vee at 80
feet is far inferior to the 4 square I had planned.
Ideas and thoughts on this?
Bill K4XS/KH7XS
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