[TowerTalk] Erecting a tower with a block-and-tackle and gin pole

[Jim Lux]

At 10:50 AM 8/11/2007, Donald Chester wrote:
>I recall reading an article in a pre-WWII radio publication about raising a
>100-ft tower entirely with a gin pole, requiring no climbing or crane.  The
>tower was fully assembled on the ground, and the guy wire lengths were
>precisely calculated using a  transit level, and cut to  length.  Two sets
>of permanent guys were connected to their anchors, while the third set was
>left unattached.  A temporary set of guys was attached to the tower and to
>the top of a rigid pole, which was then hoisted to a vertical position.  A
>couple more temporary guys were attached to the top of tower, anchored 180
>degrees apart.

This sounds like a variant of the falling derrick technique described 
on this list a few times by Rick, N6RK (I think he has pictures and 
diagrams on his website, too). A key question would be how long is 
that secondary pole?  20-30 ft?
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