Requirements:
First and foremost, the mast and all other structures must be serviceable either from the ground or reaching out of the attic window.
Secondly, it must minimize any changes to the house. Plan for the time it will be removed from the premises.
Finally, Cape Cod is beautiful. Try to minimize its impact on that beauty to others (Obviously beautiful to a ham).
The hoist is a prime driver for the mast. The first step was to calculate the forces involved. Most greatest forces exist when the mast is near the horizontal and we start to crank it up. Ignoring the weight of the coax and rotor wires, the mast, rotor, beam, and vertical antenna weigh lbs. In the lowered position, the pull on the rope was found to be 203 lbs. The force on the pivot tends to lift up 52 lbs and push sideways 144 lbs.
The 8" x 8" x 8' timber is buried to a depth of 3.5 feet. That is enough to remain upright against the 144 lbs. And the timber is heavy enough that the timber will not be pulled up by the negative force. A 2.2" grove is cut 6 inches down from the end of the timber and a 1/2 inch bolt passed through the timber and the bottom of the mast.
The 2" x 24' Penninger mast is made of 3 sections, each having a wall thickness of 0.5 inches. We chose to mount the winch on the mast with the rope through a pulley on the mast and up to a bolt secured to the house. Running the rope in the other direction with a pulley near the top would either require the winch to be mounted on the house or, if on the timber, anchoring the timber to handle the 144 lb. lift.
Once in the vertical position, the mast is locked in place by reaching out the attic window and closing two clamps with wing nuts.
The inverted V antenna is tied to a pulley mounted on the bottom of the rotor and is hoisted after the mast is locked in its vertical position and lowered before the mast is cranked down.
A roof rake attachment was made to hook onto the
mast while it is being cranked up to supply a slight pull and guide the mast
past the house eves. The inverted V antenna actually goes over a portion of the
house. The modified roof rake is also used to guide those wires as they are
being lifted.
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