[Towertalk] CRANK UP TOWERS

[Bob Thacker]

I have an RBZ-66 EZ-Way tower that was manufactured in 1965. It has a 7
cubic yard concrete base that is 7' deep. Over kill according to 1965 specs,
but nonetheless adequate for today. The original galvanizing is in very good
condition. One of the reasons that the township was receptive to granting a
permit was the fact that it could be lowered in high winds or lowered behind
a tree line and minimize visual impact. Made the case a lot easier.

It was purchased second hand in 1991. The cables have been replaced twice
and all pulleys have been rebushed with new Fafnir bearings. The cable was
replaced because yours truly screwed up and accidentally kinked it in 1994.
There is no sign of rust or corrosion on the current cable as of last fall,
spring maintenace may show otherwise. A fellow ham designed a handy remote
control mechanism that has a height meter that can drive the motor from
inside the house with up/down limit switches. Everything mechanical was
inspected and replaced if necessary, which was about everything. The .250"
20'  chrome moly mast supports a TH11 and a 402BA with steps in between.
Next project is a wind speed indicator that will audimatically lower the
tower above a specified wind speed. The tower also supports 2 wire cages
that linear load the tower for 80 and 160. This actually was my dream
antenna installation as a kid and it preforms very well. The only thing I
might change, and probably will, is to put up F12's, 5BA and EF-30/40. Well,
maybe.

There are 2 maintenance inspections per year and there is no mechanical way
to support the sections from collapsing other that the supporting cable.
Therefore, steel bars are placed at 2 stategic locations to prevent the 2
inner sectionsfrom collapse while climbing. It can be tilted over, but opted
not to remove too many trees that would deminish the visual impact to
others.

I would not do this project again because it literally took years to
complete. "Only reason". Saving a buck it not always the easiest. Crank ups
are great if you buy new, therfore you don't have to replace every blasted
thing.

My vote is for the crank up, as long as the preventative maintenace is
preformed and proper safety techniques are followed.

73,

Bob, K3GT