At 03:15 PM 10/16/96 -0400, you wrote:
>In a message dated 96-10-16 13:41:54 EDT, you write:
>
>>Should have mentioned that the Preforms for 3/16 and 1/4 inch
>>guy wire really don't have a big enough loop to go around the
>>leg and the two vees properly.
>
>John --
>
> According to my Preform specs, the 'seat diameter' for the 3/16 inch grip
>can be from 1 inch to 1-3/4 inch around a pin. You can go up to 2-1/2 inch
>through an insulator but then you use the SECOND cross-over mark to start
>your wrap.
>
> Adding the 1.25 OD leg size to the 5/16 inch brace rod size for 25G
>(times 2 because you're going around two braces) gives a 2.5 inch diameter -
>too big for the Preform grip spec. John, your option of using a short swaged
>pigtail to use as the tower termination would be the only way to go. The big
>problem, of course, is that you don't have the torsion resistance of the guy
>assemblies.
>
> For a 1/4 grip, the minimum is 1-1/8 inch but the maximums are the same
>as 3/16.
>
>73, Steve K7LXC
Steve,
These calculations don't quite work out this easily since the vees
are vertically separated and the plane of grip loop has to be twisted
to about 45 degrees to the plane of the leg--stretching everything by
at least root two.
The torque arms don't buy you very much for torque resistance but I
still like them. Heard that Rohn had discontinued them at one point
since their effectiveness was so minimal but the ham community
insisted on getting them and they brought them back.
I still prefer the big triangle and the double guys--which is what I have
on the tops of my 200ft 55s. Doubles up on the guy strength--have a
pair of 11,000 pound Phillys in each direction--like the redundency
as well as the big 22,000 pound rating.
John
BTW Steve, thanks for the reprints.
John Brosnahan W0UN
24115 WCR 40
La Salle, CO 80645
"Radio Contesting IS a Contact Sport"
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