[TowerTalk] Re: Protecting Steppir control cable

[Jim Lux]

At 02:15 PM 3/23/2004 -0600, Didier Juges wrote:
>Polyphaser sells a rotor cable protector for 8 wire rotor cable. That may
>work well for the Steppir (you may need more than one). It is rated 24VAC.
>
>That raises a question: where do you buy the Polyphaser stuff from? They do
>not have a list of distributors on the web site, and they don't seem to
>sell direct either.
>
>73,
>Didier KO4BB

There are also vendors like ProTek who make transient suppression products 
for the data acquisition and telecom markets.

I would suspect that products aimed at the telco market might be a lot 
cheaper, since they are produced in huge volumes. There's probably some 
sort of price/benefit analysis that one could go through to determine just 
what sort of transient protection you need.  A lot depends on what your 
Mean Time to Repair (MTTR) and the cost of sacrificial components is.

For instance, I wouldn't have much problem with a scheme that caused a 3 
foot section of cable outside the house to get blown up on a direct strike, 
as long as the stuff on the inside was protected.  The few hours or days it 
would take to get around to fixing it is probably acceptable for amateur 
use.  If, on the other hand, you're a commercial provider, and have outage 
time limits in your contract, or, if your installation is in a location 
which is a pain to get to (mountaintop repeater reachable by helicopter, 
for instance) you might want something that's a bit more robust and "self 
healing".

One might be able to adapt fairly standard Cat5 transient suppressors for 
this kind of use (especially if they have one of those $X,000 attached 
equipment warranties(!)).  The voltages are probably in the right range, 
and who cares if the $10 surge suppressor gets blown up... it's 
sacrificial. (I'd want to read all that fine print in the warranty, though... )

Jim, W6RMK