To clarify, it was the original straight fiber version of Philly-strand that
we had problems with at WDAE AM 1250 KHz.
We were able to successfully compensate for the inner strand slippage
characteristic by adopting a greatly lengthened foldback, large thimbles,
and lots of clamps.
If you do use the original straight strand version Philly-strand, just be
aware of the slippage issue, adopt a more thorough system of clamping, and
inspect it frequently!
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com]On Behalf Of James
Wolf
Sent: Tuesday, January 14, 2014 8:23 AM
To: topband@contesting.com
Subject: Re: Topband: Ends for older Phillystran
On 01/13/2014 04:15 PM, Lloyd Berg - N9LB wrote:
> Hi Grant!
>
> I worked at WDAE Radio in Tampa, FL back in the 80's and 90's. The
> engineer before me decided to try the new technology Philly-strand guy
> lines on the AM directional towers because they had constant problems
> with the original segmented steel guy wires/egg insulators constantly
> arcing over whenever there was a thunderstorm in the area. To attach
> the Philly-strand, they used traditional metal saddle clamps on this
> early ( somewhat experimental ) Philly-strand installation. It was a
> real neat looking job with 3 clamps 3 inches apart and all within 8
> inches of the ends of the Philly Strand. Just like you see on steel guy
lines.
>
> It was written up in Broadcast Engineering Magazine with lots of
> pictures as the wave of the future for AM broadcast guyed towers.
>
> In reality, it didn't work well because we were constantly having to
> re-attach the lines because the inner strands pulled short inside the
> outer sheath, leaving just the outer sheath holding the tower up! ( nude
towers,
> no antennas on top ). It didn't take long before we realized that we
had
> to use a lot more foldback length and a lot more clamps! We went with 36"
> foldbacks with six clamps evenly spaced to keep things from pulling apart!
> That worked and stayed together for the remaining 10 years I worked there.
> Yes, we had to insert 6 feet of steel line at the anchor points to
> make up for the lost length at each end of each guy lines.
>
> No guarantees, but that was my experience with the original Philly-strand.
> If you decide to keep it, be very careful and inspect it frequently!
> They don't make that original Philly-strand for a good reason.
>
> 73
>
> Lloyd - N9LB
Lloyd,
Was this the Phillistran that did not have the inner strands in a rope
configuration or were they just straight fibers?
Thanks,
Jim - KR9U
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