It is more accurate to say that rotators are not likely to be damaged by
lightning. However, since mine was damaged, it is obvious to me that there
are some cases where lightning is going to damage or destroy something, and
not much one can do to prevent it.
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Gary Schafer
Sent: Thursday, December 14, 2006 2:45 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Lightning damage to rotor housings (Was:
Whichthrusebearing?)
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
>
> _______________________________________________
>
>
>
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