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Topband: Shunt fed tower: PLEASE HELP (long)

To: 160m Reflector <topband@contesting.com>
Subject: Topband: Shunt fed tower: PLEASE HELP (long)
From: Sante - IK0HBN <ik0hbn@libero.it>
Date: Tue, 25 Nov 2008 20:38:18 +0100
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi Topbanders,
I really need your help. I beg your pardon as this message is long, 
but I'll do my best to be clearer as I can.

At last, after 14 years my Gap Voyager is died for age, so I took 
courage with my 2 hands and I decided to improve the low band in one shot.

I ordered a 35 meters pole with 3 meters buried into the concrete 
block. The company will put a rail to permit my future yagi for 40 
meters to be elevated with an hazer, as I never been able (for fear) 
to climb a tower.

So the out of the ground will be 32 meters.
The diameter at base of that pole will be 925 mm and on the head will 
be 240 mm. On the top will be a pulley that will permit the hazer 
hosting the rotator and the mast + a 3 el. yagi for 40 mtrs to go up and down.

Hanging with insulated wires there will be 4 verticals for 80 meter 
to be phased with Comtek box.

At 90 degrees versus the rail/hazer, will be put a stair that should 
allow (hope never) something to climb the system in case of broken 
rotator that should not allow the descending of the hazer/antenna.

The shunt fed system will be opposite to the rail/hazer and at 90 
degrees versus stair.

I need to know, more and less, where to put the"arm" for having all 
the system shunted for the topband. (at which height and how far from 
the pole).

I well know that for an increased bandwith I will have to put a 
triangle of descending wires, but what I do not know is :

I know that it's difficult to say without calculating it, but I rely 
on your experiences of many years.

The arm must be soldered to the pole before it will be hot-dipped 
galvanized, and last but not least, I will be not able to climb up 
and down to find the best match.

I have thought at an OMEGA MATCH, but suggestions are welcomed.

As the hazer will support a 3 El. yagi for 40 mtrs, is there a 
"minimum" safe distance from the yagi to the "shunt", up on the tower?

Beside: making treasure of your experience, will I expect troubles in 
putting also the 4 square for 80? How down respectthe Yagi the 
insulated wires should start?

My pocket allows only a tower for 3 bands.., so everything must stay there :-)

For ground, I have thought to close the field with a fence and bury 
radials 3 or 4 cm under the ground for the topband. For 80 meter, I 
have still not clear idea how could I resolve radials matter.

I am trying to give directive as precise as I can, because all the 
changes asked to the building company after the subscription of 
project, would cost me much, but very much, so having ideas as 
clearer as I can, surely will help me.

I solemnly promise here that I will summarize your replies and when 
all the job will be put to an end, I'll share the pictures with all you.
TIA
Sante
ps. For the moment I am playing with a KX1 and 3 watts, for lacking 
of antennas...
Best luck to all will do the CQWW next week! 

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