In a message dated 99-04-12 11:32:51 EDT, you write:
> > Don't forget that a crank-up has cables connecting all the sections.
> > It's one big lump of steel as far as being a conductor is concerned.
>
> Yes, but I'd be concerned that the sections are electrically bonded only
via
> the contact area between the steel cables and pulleys. Wouldn't
> dirt/lubricant on the cable and in the pulley grooves tend to make that
> contact unreliable?
I'll bet you a nickel that there is still an adequate electrical
connection. If you look at the races of the pulleys, they are generally bare
metal. Running the tower up and down with the cables under pressure does a
pretty good job of keeping oxidation off of those parts.
I'll try to remember to take a DVM with me the next time I'm on a
crank-up and measure some of those points.
Lubrication? What lubrication? 98% of hams have never lubricated their
cables so that's kind of a non-issue.
> I've seen recommendations on bonding crankup tower
> sections together for the purposes of improving lightning protection, but
> always felt that was not really feasible.
You're right - it's not.
Cheers, Steve K7LXC
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