In the beginning, there needs to be a word- like "THANKS" to Kurt, and the
people like him, who are truly professions, but share so much with us.
then- I still have a quibble with acceptability of the combined usage of
the Aramids and EHS tegether. See below.
At 02:08 PM 9/1/98 -0700, you wrote:
>
>> John Langdon ( N5CQ ) pointed out a usage (very common, in fact) of both
>> Phillystran and EHS, together, that is proper, and OK. This is the use of
>> the two in series to break up conductivity, using Phillystran, with EHS at
>> the ends to give mechanical and fire protection.
>
>This is a common, recommended practice.
>
>> He is certainly right- I was meaning only parallel usage.
>
>"Don't do this!" Cables with different elogations will not load share
>properly.
>
True, but this is only a problem when the load is split, as in the use of
different guys with different materials. This (load sharing) is a disaster
looking for a time to happen.
However, in many cases, such as the commonly recommended practice of
combining the two materials in one guy, the load is the same in both
materials (series hook-up) , and the load is not 'shared', as in 'split'.
Many people use a guy arrangement that uses one of the Aramids for most of
the guy, and use EHS at the base. This is done to provide greater
resistance to abrasion, physical and fire damage, while having an RF inert
guy, for the most part.
Bill
Bill Aycock W4BSG
Jackson County, AL
EM64vr
W4BSG is "vanity" this time, but was
earned by exam in 1954, the first time.
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