In a message dated 4/2/02 7:10:11 AM Pacific Standard Time,
k1ky@bellsouth.net writes:
> I have measured the resistance between Thrust Bearings/Rotors and their
> mounting
> points. It isn't a pretty picture, usually something like 10-30 ohms.
Interesting. Was the measurement on the bench or on the tower with
vertical weight on it? I suspect that the weight would compress the bearing
more and decrease the resistance slightly.
> This
> could explain why the rotor is usually one of the first to go as a result
of a
> strike or nearby hit.
>
Is that right? Since it's attached to the mast, a direct strike would
make sense. The rotator is chock full of places for the strike to arc as
well, unlike the simpler tower and antennas.
> I take a #4 flexible conductor and tie it to the mast and then the tower
> below the rotor mount. No problems to far.
This may be more psychological than real help. If it's stranded, the
strands will oxidize over time which increases their resistance. Any bends in
the jumper will discourage the transient from following that path as well.
Maybe you've been lucky.
Cheers,
Steve K7LXC
TOWER TECH
|