It should be obvious that un-authoritive or is it
un-authoritative Gary's laws of physics don't apply.
And thanks to Bob for doing the 'leg-work' to put another
Tower Talk myth to rest.
Doug/VA5DX
Well, after all that "authoritive" reporting I don't think
anyone should
ever worry about lightning damaging anything on a tower
again. Why spend the
time to bypass or ground anything. If no authoritive figure
ever sees the
damage then it must not exist in the first place. Even
though the laws of
physics tell you differently.
73
Gary K4FMX
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Robert Chudek - KØRC
> Sent: Thursday, December 14, 2006 4:20 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Lightning damage to rotor housings
(Was: Which
> thrusebearing?)
>
> Okay... you guys theorized ever which way to Sunday about
damage to rotors
> from a lightning strike. Most everyone on the list has had
a rotor or two
> or
> three during their radio career. I'll be blunt, I didn't
like your
> suggestions and all the jerry-rigging ideas that were
being tossed about.
> So
> I went to the experts. The two companies that have been in
the business of
> rotor sales and service. That would be C.A.T.S. and
Norm's. Here's my
> information request and the replies I received from them
both:
>
> KØRC>>>Hello Dr. Rotor (Craig) ! There is a discussion
warming up on the
> TowerTalk reflector regarding lightning damage to rotor
housings when an
> antenna mast is struck and discharged down through the
tower to ground.
> What
> kind of damage have you seen to rotor housings, bearings,
balls, and races
> over the years? I am curious about physical damage more
than electronics
> being destroyed. Does the bearings and races provide an
adequate, low
> resistance path for a high current discharge like this?
Thanks in advance
> for any insight and real-world experiences you can
provide. 73 de Bob -
> KØRC
> in MN
>
> CRAIG>>>Hi Bob :
> Sounds like most of the discussion is pure conjecture and
no one has yet
> chimed in from experience.
> OK, from 30 years of experience working with rotators : A
metal housing
> protects the interior parts, as does the framework of the
tower structure
> surrounding a rotator. Lightning damage to a rotator has
been almost
> unheard
> of; with the few cases we have seen suspected of coming
from the surge on
> the cable itself. In my early days when I was in the TV
antenna business,
> I
> saw numerous cases of the rotator wiring arcing over to
the legs of the
> metal tower and the rotator itself surviving just fine.
> Now, I would suspect that a rotator with a streamlined
design from top to
> bottom would be the least susceptible to a lightning
surge; but I haven't
> seen enough data to back this theory up.
> Oh, and to answer your other question. Never ever have we
seen any damage
> to
> bearings or races.
> Craig,
> C.A.T.S.
>
>
> KØRC>>>Hello Norm...
>
> There is a discussion warming up on the TowerTalk
reflector regarding
> lightning damage to rotor housings when an antenna mast is
struck and
> discharged down through the tower to ground.
>
> NORM>>>What kind of damage have you seen to rotor housings
[none],
> bearings
> [none], balls [none], and races [none on any of these
that I can
> attribute
> to lightning] over the years? I am curious about physical
damage [I don't
> see much physical damage, I did have one with a broken off
upper mast
> support but that was because the whole tower came down in
the lightning
> storm] more than electronics being destroyed.
[Everything I get in has
> burned up electronics mostly in the control units with
lightning coming
> down
> the rotor cable.] Does the bearings and races provide an
adequate, low
> resistance path for a high current discharge like this?
[maybe if they
> suffer severe physical damage, guys just chunk them and I
never see them,
> I
> don't know. This is all based on what I recollect from the
dozen or two
> over
> the last few years.]
>
> Thanks in advance for any insight and real-world
experiences you can
> provide.
>
> 73 de Bob - KØRC in MN
>
>
> So there you have it. Create a rube goldberg solution to a
non-problem if
> you like. I'm not going to waste any time, energy, or
money protecting my
> rotor housing from lightning. Oh, and I can speak from
experience, my
> tower
> has been hit by lightning numerous times and I have never
had any damage
> to
> the rotor on the tower.
> 73 de Bob - K0RC
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.5.430 / Virus Database: 268.15.15/580 - Release
Date: 12/8/2006 12:53 PM
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.430 / Virus Database: 268.15.15/580 - Release
Date: 12/8/2006 12:53 PM
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|