[TowerTalk] Grounding stub mast

[kb9cry at comcast.net]

ith the stub mast mounted to the rotator and top bearing is there any need
to ground this stub mast independently to the tower or will the thrust
bearing/rotator provide an adequate path?   

Theoretically yes the mast is grounded to the tower via the thrust bearing.  But if it is not making a good low resistance connection then energy surge may travel down the mast into the rotator.  That may not be a good thing since there's small motors and potentiometers inside that might get fried.  What I do is attach a clamp onto my masts inside the tower just below the thrust bearing top plate and jumper between that to the tower leg with #4 welding cable.  Some folks I know use wide braid for this application.  Leave slack for rotation.  Now the energy surge will hopefully shunt via this route rather than the rotator.  One can never be too grounded.  Phil  KB9CRY