Topband: 450 ohm ladder line used as 2W Beverages

[n0tt1 at juno.com]

Hi Larry,

On Fri, 19 Mar 2004 18:24:05 -0500 "Larry Emery" <k1uo at prexar.com>
writes:
> What is a good way to support this stuff over an 880ft run? 

I use 2" x 10 ft white schedule 40 PVC pipe called "cell core".  It comes
in
20 ft lengths at farm supply stores and is very economical.  
I just cut it in half and carry it home in my truck.

I fastened the line on the poles with a single stainless steel
1-5/8 inch "deck" screw and a Red Snapper Brand "Poly Tape
Wood Post Electric Fence Insulator" part number PT25WP.
I have used other types...this one is the best IMHO.

For the end poles I use a homebrew strain insulator made from
1/4" Lexan(r) plastic, then solder on the downlead (same type twin lead),
taping the twin lead to the upper part of the pole.  On the
lower part of the pole I use another type of Poly Tape insulator
that is about 4 inches long to space the twin lead away from the
PVC pipe becasue the pipes are all supported by some heavy
duty fence posts.   The long insulators are modified by cutting
off part of the "gripper" so the line can run down vertically while the
insulator is mounted in the normal manner.  I drill a horizontal
hole behind the end and fasten the twin lead with a heavy plastic
tie wrap.

The end poles are back guyed with a single 1/4" rope
and a screw-in type of earth anchor.

For my forested area I use some convenient trees as supports.  On
some trees I use a ~2" length of  1-1/2 PVC pipe that has a 
slit cut in the top and at a slight angle.  I drill a small hole through
the side of the pipe at the middle, then enlarge one of the holes
to pass a screw and screwdriver.  The pipe is then attached to
the tree with a stainless steel deck screw and the line is
then slipped in thru the slit.   I found that if any heavy tree limbs
fall
across the twin lead, the pipe will break away becasue of the slit,
saving the line from damage.

> What
> orientation is best, wires vertical or horizontal with ground, or does
> it even matter.
>  What is the purpose of twisting every 10 or 20 feet as mentioned 
> in
> ON4UN's handbook?

Twisting provides balance to ground and also keeps the line from
whipping in the wind.  I install a odd number of poles, then
once the line is up and tensioned I go to every other pole and
twist the line maybe 10 half-turns.  My poles are spaced every
70 feet or so.

73,
Charlie
N0TT