G'day folks,
| part of my reason for asking is that i might eventually install a small
40'
| crank up and wanted some information on how these things work in order
to
| make a decision. It sounds as if when the tower is fully or partly
| extended, the cable continues to hold the weight of all the sections.
Is
| this true? Or is the cable only supporting the sections when raising
and
| lowering the tower, and other times there is some sort of locking
mechanism
| that can be released into place?
I have a two section 12 metre Heavy Duty "Versatower" made by Francis and
Lewis in the UK. On this there is a butch steel flap on the first section
that is lifted by the passing bracing of the second section. The flap
falls back into place as each bracing passes. At the maximum extension
there is a heavy duty brace that is lowered to sit on the top of the flap
and tension is thus taken out of the wire. To lower the second section
you just wind it up a couple of inches so that the flap can be disengaged
and held clear by pulling down on a rope and tying it off during lowering.
The tower itself is hinged about six feet from the bottom on a base mount.
Not a cheap toy but my wife insisted I stop swinging about on my previous
utility pole and ally tube assembly. Sure makes antenna work less
trouble. My current antenna, a five element log 18-30MHz, is at about 42
feet and turned by a PST61D rotator which doesn't even notice it. It pays
to build strong in the Falklands, we get a lot of wind. The log really
isn't up to it and I'm sourcing suitable tube for some of the heavy duty
ARRL Ant. Book Yagi designs. Either that or an Optibeam 10-3W or 9-5.
Regards,
Mike VP8NO
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