> think for my urban lot a reasonable height limit is probably
> about 75?. One of the European verticals probably isn?t a
> realistic option for me, so that has left me pondering a homemade
> vertical antenna, which would be constructed of aluminum tubing
> from the common amateur radio sources. I?d love to use irrigation
> pipe, but I don?t find any distributors listed in the local
> yellow pages. So that may not be an option for me. Also, I am not
> sure how I one goes about transporting the pipe to their house?
Some recent experiments with irrigation tubing:
All tubing .050 inch wall.
A 60 foot vertical with the bottom half 3" and the top
half 2" can be walked up (actually did this).
A 90 foot vertical with the bottom 30 ft 4", the middle
30 ft 3", and the top 30 ft 2" can be pulled up using
a 30 ft piece of 3" as a "falling derrick". I put up
two of these last month by myself. A total piece of cake.
Joints between dissimilar sizes are made using a 1 foot
length of Sch 40 PVC pipe of each size connected by an
ABS bell reducer using pipe glue marked "PVC or ABS".
The irrigation tubing is then slipped into the PVC and
clamped (slits are cut near the ends to allow the PVC
to be clamped.) Aluminum stovepipe tape is used to
metalize the PVC for electrical conductivity.
Wind survival is based on how much guying you do; the more
the better. I used 440 lb baler twice (1/2 cent per foot)
so I could put in as much guying as I wanted for practically
no cost. A lot of lightweight guys are better than a few
Phillistands.
For transporting irrigation pipe, various ideas:
1. Ask if the dealer provides delivery. It cost me $90
once to get the tubing delivered from 40 miles away.
2. Cut the tubing in half. It is very easy to splice it
back together again using a sleeve with a longitudinal slit.
3. In a minivan with a rear window that opens (not all do),
you can go thru the rear window and the passenger side window.
You can typically get away with 5 or 10 feet sticking out the
front, 10 feet in the van and 10 or 15 feet sticking out the
back with a red flag. Of course if you cut it to 15 ft,
then the minivan is really easy.
4. A truck with a lumber rack will work.
Rick N6RK
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