At 03:34 PM 6/28/2005, W2RU - Bud Hippisley wrote:
> > -----Original Message-----
> > From: jonklinkhamer@comcast.net
> > Subject: [TowerTalk] Guy detailing
> >
> > I'm...wondering if there is a inexpensive way of
> > placing the Guy anchors so that I achieve 120 degrees
> > seperation....[M]y terrain is very uneven not to mention its in
> > the middle of the woods.
>
>I had a similar situation. I made a "ruler" out of a two-foot-long 2 x 4
>that spanned two legs of my Rohn tower at eye level. With a black marker I
>made very visible equal divisions or "tick" marks (one-inch spacing is good,
>but not necessary) along the ruler, and a BIG distinctive mark at the center
>division of the ruler. I then suspended the ruler in twine slings at eye
>level from the two legs and slid the ruler back and forth in the slings
>until I had an equal number of tick marks between the center mark and each
>of the two legs.
A similar approach, lending itself to "one person" operation, is to get an
inexpensive laser level and clamp it across the tower so that it points in
the right direction. Then, hike out however many feet and look back at the
tower and walk back and forth until you see the laser beam. You won't see
a spot (unless you do this at night), but looking back, you'll certainly be
able to tell when you're along side the beam, because it becomes quite
visible. I hesitate to recommend actually looking back into the beam. The
inexpensive diode lasers are fairly far down into the red spectrum where
the spectral response of your eyes falls off, so they don't look too
bright, but the incident power is still high enough to possibly cause
retina damage. There are also nifty little beam detectors with a photocell
that work quite nicely.
One could also use an inexpensive laser pointer (they give them away at
trade shows) and tape it to a piece of wood to strap onto the tower.
If the tower's not up yet, mount the laser level on a photo tripod. Lots
of tripods actually have hash marks on the pan head which make it easy to
do 3 shots 120 degrees apart.
By the way, if you don't want to go to the trouble or hassle to measure 120
degrees with a protractor, etc., make use of the fact that three identical
circles placed in contact will be separated by 120 degrees, and 7 circles
clumped together make a hexagon with 60 degrees between
faces/diameters. Try it with coins on a table top. For your improvised
surveying, things like coke cans, paint cans, new rolls of duct tape, etc
work nicely. I prefer the 6 in a hexagon around a central 1, because you
can lay the sighting device along the joint between adjacent circles.
There are a lot of improvised sighting devices you can use.. Drive 6
stakes (4-6 ft high garden stakes) in a hexagon 4 or 5 feet across at the
tower site, then walk out the right general direction, then walk back and
forth until the stakes line up by eye. For this to work, the stakes MUST be
vertical.
You lay the hexagon out by using 3 identical stakes. Lay 3 in a triangle,
with one corner at the middle. Drive in two of the stakes at the other
corners. Move two of the stakes to make a new triangle next to the old
one. Drive another stake, repeat until all 6 stakes are in. No measuring
required.
Jim, W6RMK
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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