Charles Harpole wrote about "positive pull down" for crankups in high
wind.
I've had to deal with positive pull down . . . not for high wind
conditions . . . but because a friend of mine had a crankup that kept
binding when cranked DOWN about 25% of the way from the top.
We designed and installed a system using an ADDITIONAL manual winch in
order to pull the tower sections down. It was pretty straightforward
except for the cable configuration at the attachment point on the top
section. After some trial and error we came up with the way to make the
cable pull evenly on the triangular cross section of the tower.
His tower still binds but the pull-down winch gets it past the binding point.
73 de Dave KB0ONF
kb0onf@juno.com
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