[TowerTalk] Antenna/mast height above tower?

[Phil Camera]

Two of my towers use TailTwister rotators which have a mast clamp that allows the mast to be moved sideways a bit from the rotator in order to free up the rotator.  Actually what I do is to place a small scissors jack underneath the boom to mast plate and jack the antenna and mast up by a couple of inches to free it from the rotator.  To prevent the bottom of the mast from moving too far sideways, I install a piece of uni-strut slotted channel and a muffle clamp to hold the mast in place.  I can then remove the rotator and replace it.

For the big tower, I'm using an AlfaSpid rotator and for it, one must jack up the mast about 5 inches to free it up.  This system has a top thrust bearing and then there's another rotator plate (no thrust bearing) which captures the mast from excessive sideways movement.  I have about 4 feet clear from the top plate to this second plate.  The plan here (which I will need to do soon) will be to install a piece of uni-strut right under the top plate.  Attached in the middle alongside the mast will be a pulley(openable wicket marine/sailing type).  I'll then attach a mast clamp down near the second plate.  Then I'll install a come-along that will pull upwards from the clamp to the top pulley and then down again.  I do this since this way I'm not operating the come-along near one of its ends of travel and the actual come-along lever assembly can be outside of the tower allowing freedom to operate it.  I've never done it (will be soon this year) but did do a trial run prior to ins
 tallin
g the tower (best place to learn is on the ground not up on the tower!!!).

Sri to kidnap the topic into a rotator removal one but mast height inside the tower should also be considered along with mast height outside the tower.

Phil  KB9CRY