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Old July 5th 08, 12:27 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Jun 2006
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Default SWL Newbies : Matching the Antenna Ballast Weight to the Wire AntennaElement

On Jul 4, 3:54*pm, N9NEO wrote:
I'm in the middle of putting up a longwire antenna. *One end is going
up in a tree in my back yard and the other end is going into one of my
neighbors trees. *I think it's going to be about 150' *long *Should I
use a counter weight at my neighbor's end or try and fashion some sort
of grappling hook out of coat hanger and get it tangled up in the
tree? *My friend thought 5 lbs of ballest thrown over a limb would do
it, but I think I'd need about 20 lbs. *I'm worried about sticking 20
lbs of something or other up in the air. *With my luck it would decide
to fall when some little kid was under it. *Neighbor lady told me no,
I can't use her tree, but she is moving out in a few days anyway so I
figure to hurry up and get it up so it's there before the new owner
gets there. *Grandfathered in so to speak. *Ideas?

regards,
NEO.


N9NEO,

? grappling hook out of coat hanger ?
! NOT A GOOD IDEA !
http://www.flickr.com/photos/opalmirror/1641086431/
-ps- Yes - It is Easier to Ask for Forgiveness . . .
Then To Get Permission ;-}

50+ Feet of 1/4" Poly/Nylon Rope up over a Tree
Limb and going around the Trunk of the Tree with
the Free-End Secured at the Base of the Tree.
-Note- Pulley Attached to the Top-End of the Rope
for Rigging the Antenna Wire and Poly/Nylon Ballast
Rope and Ballast Weight.
-Tip- Allows you to Raise and Lower the Antenna
Wire and Poly/Nylon Ballast Rope and Ballast
Weight as needed.

Question - What Kind of Antenna Wire are you using ?
http://www.thewireman.com/antennap.html

Matching the Antenna Ballast Weight to the Wire
Antenna Element :

1st - Take your ~150 Feet of Antenna Wire and
coil it up. Next Weigh the Wire. Then Multiply
the Weight of the Wire by Three Times (3X).

2nd - Take a Plastic Bleach Jug filled with Road
Mix or Gravel to Equal Three times the Weight
of the Wire.
-Note- This is your starting Ballast Weight : Which
should result in a relatively Horizontal [Flat] Antenna
Wire with only a slight 'sag'.
-Tip- If your Antenna Wire is being Whipped around
on a Windy Day : You Need More Ballast Weight.

Sufficient "Sag" for Wire Antenna Spans for Wind Survival
http://www.vk1od.net/rigging/sag.htm

-Note- # 14 AWG Insulated Copper Wire [THHN] made
of 19 Strands weighs about 25 Pounds per 1000 Feet.
-so- 150 Feet would weigh about 3.75 Lbs resulting
in a Ballast Weight of 10~12 Lbs.

3rd - Use a Pulley at the Far-End Anchor-Point of
http://en.wikipedia.org/wiki/Pulley
the Antenna Wire. Use a Poly/Nylon Rope that is
big enough to fill the Pulley Wheel and Run Smoothly
through the Pulley.
http://www.qsradio.com/Antenna%20Pulley%20lg%20reg.JPG

4th - Use a Plastic Insulator at the Far-End of the
Antenna Wire and use about 10~15 Feet of Poly
Nylon Rope between the Insulator and the Far-End
Anchor-Point (Tree); with another 10~15 of Poly
Nylon Rope hanging down from the Pulley with
your Ballast {Jug} attached.
http://www.myinsulators.com/sluggo/i...tic-strain.jpg
http://www.myinsulators.com/sluggo/i...ompression.jpg

5th - Also use a Plastic Insulator at the Radio-End
of the Antenna Wire and use a minimum of 3~5 Feet
of Poly/Nylon Rope between the Insulator and the
Radio-End Anchor-Point (House/Tree).

Question - Do you get Snow and/or Ice during Winter ?
Answer - Then Triple your Ballast Weight.


rigging a shortwave radio listener's (swl) antenna
is a balancing act between the forces of man
and the forces of nature - iane ~ RHF {pomkia}