I used 29 feet of EHS per guy, which put the lowest Philly at about 10' above
ground (a somewhat tricky calculation as the tower is on steeply sloping
terrain.) The tower is in a mowed field where grass seldom gets over a couple
feet high and our climate is rarely dry, so I wasn't worried so much about
brush fires as vandals, critters, etc. I didn't consider resonance as the EHS
is quite far from the tower. I added about 10' per guy for looping it back
through the turnbuckles, probably a bit more than needed but I found uses for
the extra EHS.
All three of my 4-el SteppIRs are on TIC rings about one foot above a guy
bracket. I hadn't considered that the relatively short preforms could interact
with the antennas. Can't say I've noticed any changes in SWR with rotation, but
can't say that I ever checked it, except to see if there was interaction
between the top SteppIR and the 40m beam 15 feet above it at the top of the
tower. I'll have to check. FWIW, my preforms are attached to the guy brackets
with heavy-duty shackles. I assume there's continuity, but that's something
else to check.
I imagine it would be a big project to add insulators to my setup, so before
doing that I'd make the effort to check the pattern with modeling and some
real-world measurements.
73, Dick WC1M
-----Original Message-----
From: Ron WV4P <wv4ptn@gmail.com>
Sent: Wednesday, October 2, 2019 3:11 PM
To: towertalk <TowerTalk@contesting.com>
Subject: [TowerTalk] EHS leads for Phillystran
Good afternoon !
Having heard enough negative on the Polygon, we have shifted to Phillystran..
What I have read says you must run EHS Leaders (I have Plenty in stock) but not
over 50% of the total guy length in EHS.
Doing some modeling (not very good at) and reading, it looks like 41' of EHS
would work well for not being resonate, being plenty high up to not worry about
fire / vandals / beavers.
41' would also save a good bit of $ on the cost of Phillystran for 5 towers.
Any advice ? to long ? Just right ?
Thanks in advance.
Ron, WV4P
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