January 1961 Popular Electronics
 Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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Even though more than
six decades have passed since this article appeared in Popular Electronics
magazine, the principles and tips provided for securely and robustly guying
antenna towers still stand (intentional pun). Jack Darr, who wrote many PE
columns on topics including radio and television, has a pretty big bag full of
tricks for installing, operating, and maintaining equipment. His electronics
theory and troubleshooting pieces were epic back in the day when there were such
things as antenna installation crews and electronics service shops. Antenna
tower design and materials have come a long way since the welded iron and steel
tubing jobs of yesteryear, as have guy wires, turnbuckles, and anchoring
hardware, but you still need a good grounding (another pun) in basic mechanics
to assure a safe and long-lasting tower and antenna. Of course there are not a
whole lot of TV antenna towers around anymore, but Ham radio towers abound if
you look for them whilst out cruising about.
Guying Tips for the Ham Antenna Tower
 By Jack Darr
There was a time when amateur radio antenna towers were usually homemade affairs.
But the widespread use of commercial ham and TV antenna towers has made the homemade
tower almost as obsolete as the spark-coil transmitter.
Telescoping masts are ideal supports for light or medium-weight beams and can
also hold up the ends of a doublet. For heavy beams, you can buy a mast that is
bigger than you need, remove the upper sections, and end up with a tower strong
enough to carry the load.
A tower won't carry your antenna for long, though, unless it is properly guyed.
Never skimp on the guy wires and supports - a beam and rotator cost far more than
a 50-cent length of wire.
Ratchet take-up anchor (two views, top) hauls in guy wire slack
with the twist of a wrench. Another type of anchor (center) is a simple aluminum
fitting with an eye for fastening guy wires. Lag screws and lead shields (two views,
bottom) secure anchors to concrete; screw expands shield in drilled hole for tight
fit. Tall towers and masts require guy wires running to the top and middle sections
as well.
Two guy wires can be attached to the same ring for medium towers,
but high towers should have separate rings to anchor guys.
Always use a metal ring when you attach a guy wire to a metal
tower; the sharp edges of the structure would eventually cut through unprotected
bare wire.
Be sure to ground the tower. For a rooftop job, run a length of heavy solid wire
- No. 6 aluminum or larger - from the base of the mast to a ground rod. Don't bend
the wire sharply where it goes over the eaves, however. Lightning acts like a high-frequency
signal and is "blocked" by such a bend. It may jump to a point several feet away
rather than go through a sharp bend in a wire.
Guy wires can be secured to wooden roofs with a 3" screw eye
inserted into the rafter (left). A metal thimble loops the wire through the eye
and takes the brunt of wear when metal rubs metal; twisting the wire around itself
at least six times will hold it fast. Two poor guy wire fastenings (center and right)
are examples of what what not to do.
Use a turnbuckle to get the desired tension on the guy wire,
with at least a six-turn tie and a thimble at the guy-wire end. Connect the turnbuckle
to both the guy wire and the screw eye anchor. Take up any slack by twisting the
turnbuckle's body, using an iron rod for leverage. Be sure to safety tie the turnbuckle
with scrap wire to prevent it from unwinding.
If the mast is mounted on the ground, drive a ground rod near the base of the
mast and use a U-bolt to clamp the mast and the rod together.
If you live near the sea, where corrosion is a problem, use aluminum guy wires
or very heavily galvanized steel, and spray all joints and fittings with plastic.
It's also a good idea to inspect the whole installation thoroughly at least once
a year.
Installing your antenna properly, whether it's a 150-foot tower or a 12-foot
vertical, is just a series of small jobs: tying guy wires, fastening screw eyes,
adjusting a turnbuckle, etc. If every one of these steps is done right, you'll have
a tower that will stay up under almost all conditions (short of a wind that blows
the house away). If you skip just one step you may wake up one morning and find
your tower lying in the yard. To corn a phrase, take care of the little jobs, and
the big job will take care of itself.
In three-wire guy systems, always have the guy wires equally
spaced (solid lines) to provide equal bracing against all winds. Unevenly spaced
wires (dotted lines) offer less support against strong winds.
 Four guy wires offer
maximum protection against high winds when spaced 90° apart. Avoid making angles
too wide (dashed lines) or the mast may topple during the first big storm.
 Not all four-wire guy
systems can be spaced 90° apart. A building may get in the way, or your back
yard may not have the right dimensions. In such a case, make one wire pull against
another (solid lines) for maximum all-round strength.
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