Eric,
Have a look at
http://www.n6rk.com/falling_derrick_gme/falling_derrick_gme.html
I put up a 40 ft tower (not a crank up) with small tribander plus
vertical mounted above all by myself one Field Day using the falling
derrick method. Takes quite a while to rig, though.
The trick is to use 4-way guying instead of 3. That way the lateral
guys can be made the right length and tied off before the tower goes up.
They keep the tower from slewing sideways.
Let me know if you want more details. I've got a write-up of what I did
somewhere.
73, Jim Smith VE7FO
Eric Smith wrote:
>
> I have been working on the hardware required to safely
> stand a light 55 foot crankup in a
> portable environment, provided adequate anchor points are
> available, and doing this all unassisted, without the tower
> being fastened to a vehicle or a so-called "driveover"
> mount. Quite the challenge I assure you. Trick is to fab
> up some sort of "bipod" gin pole for lifting the top end of
> the tower high enough for the line pulling the tower
> vertical to get adequate mechanical advantage to do the
> lift, and, not try to pull the tower to one side or
> another. Other trick is to have the two back guys already
> fastened to their anchor points so as to keep the tower
> from doing anything silly when the tower becomes nearly
> vertical, like fall over to one side or towards the winch
> line. I am sure it can be done with the right stuff...
> Eric
> KB7DQH
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