I have noticed recently that a number of hams seem to have a fear of
dealing with crank up towers. I have used a TX472 for more than 10 years
located first near Dallas and now near Spokane. It is not difficult to
install the tower and antennas. I recently posted to our clubs web page
information on how to replace cables and pulleys safely on it. www.sdxa.org
. Click on DX tips on the right hand side.The system described is also
applicable to installing antennas. You just step from the ladder onto the
top of the nested tower. The antenna can be lifted vertically by a rope and
pulley straddling the tower and ladder. If you were smart enough to put a
pulley on the top of the mast with a rope through it, lifting the antenna
into place is easy. If you forgot to put the pulley on the top of the mast
all is not lost. Just rig the pulley with a hook on it and attach it to a
piece of aluminum tubing to lift it up and hook the top of the mast. You can
either leave the pulley in place after you finish or lift it off and lower
it to the ground. If you tape the pulley to the tubing, you can pull the
tube loose and leave the pulley in place.
I have found that tilting the tower over to work on antennas is not a good
idea. It is easier to lower the antenna vertically to the ground. I once
lowered a 4 el yagi to the ground, changed element tip lengths and put it
back up in less than an hour.
My other crank up is a 131 ft UST unit with a 6 el Yagi on a 57 ft boom. I
use the same technique to lower and raise it except that the pulley rope is
a length of small steel cable as used on garage door openers. It is spooled
on a small hand powered winch bolted to the base of the tower. The crank
handle was removed and a variable speed electric drill is attached to the
shaft. The tower is nested and a helper on the ladder guides the antenna as
it is raised or lowered.
Crank up towers are not cheap but 2 have been sold at very reasonable
prices here as part of SK ham estates. In each case the tower had to be
taken down by the buyer.
73, Dan, N5AR
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