You always want to use EHS for several feet near the tower (falling tools,
antennas, etc.) and near the ground (grassfires, vandals, etc.).
To be sure there are no issues with electrical interactions with EHS you
should model the installation. Failing that, there are tables (in the ARRL
antenna book and others) of lengths least likely to be resonant in the ham
bands.
The more different antennas at various heights you have on the tower, either
stacked arrays or just several antennas, the more is the chance that EHS
will disrupt the patterns, where Phillystran will not.
There are also some polygonal fiberglass rods that are less expensive than
Phillystran, (see http://bit.ly/1EK6NSl for examples) but there is a
relatively large minimum order, when you can find it.
73 John N5CQ
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Andre
VanWyk via TowerTalk
Sent: Sunday, May 3, 2015 6:08 PM
To: <towertalk@contesting.com>
Subject: [TowerTalk] Rotating tower guying question
I am about to start construction on my new 165ft Rohn 55G rotating tower. My
anchors are 180ft out from the base.
My question is: Just how much is using Phillystrand cable buying me versus
using EHS cable broken up with insulators?
I don't want to cut corners on this installation but the cost on the EHS is
far lower than Philly and I am sure the lifespan is much longer too.
How about using Philly for 50% out from the tower bearings and then EHS for
the remaining 50% down towards the anchors?
Any comments / thoughts would be appreciated.
73's
NJ0F
Sent from my iPad
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