Wendell, you definitely need hardline or your losses will be severe. It can
be buried without PVC cover. I have bought lots of Andrews 1/2 and 7/8 used
at the Hamcom convention in Dallas when I lived there. Your problem will be
finding long enough runs and you might want to have surface boxes along the
way to use the available lengths and connect them. You could use 75 ohm TV
stuff and possibly 75 to 50 ohm ferrite xfmrs for the hf bands. I would
think seriously about putting the vhf/uhf stuff nearby the house. It is good
if the used hardline has connectors on it but it is easy to fab your own
with copper tubing parts. You might contact some of the guys in the North
Texas Contest Club for cable sources 73, Dan, N5AR
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Wendell Wyly -
W5FL
Sent: Thursday, February 22, 2007 9:12 PM
To: Towertalk@Contesting. Com
Subject: [TowerTalk] Help on new Tower installation planning and
Feedlines
My interests are a small station contester and a dxer and have been
doing this since 1955. Appreciate any suggestions on planning for my
new tower installation to be put in next month. Budget is approx
$2000. Distance from Transceiver to tower site is 375 feet. Tower
elevation is approx 35 feet above house and Tower is a used 64 foot
Rohn 45 Foldover tower taken down from my last house two years ago
and to be put back up to Rohn Specifications using the original guy
lines and 4 guy posts and 2 el cubical quad 5 band antenna and rotator.
All wire and conduit is new. Plan to have two HF feedlines and one
144/440 VHF feedline and 8 cond rotor cable for Hy Gain T2X Rotor and
a 4 or more small gauge (#24) wires to control the antenna switching
for 80,40 dipoles and 10/12/15/17 and 20 meter 2 el quad loops or
maybe a better antenna. Plan to use 360 foot 1 1/2 or 2 inch pvc
conduit for the feedlines and 3/4 or 1 inch pvc conduit for the
control lines to be buried about 12 to 18 inches.
Budget is kinda skimpy but always wanted to use 1/2 inch hardline due
to low loss, but don't know if it pulls through conduit ok. Trade
off is LMR 400 or LMR600 or ???. The conduit run is 140 feet to a
pull box and then 220 feet for a total of 360 feet. 1500 Watts on
HF and 50 Watts on 144/440 VHF. Looking at using preamp or two band
amp/preamp on tower for 144/440 vhf due to long coax run, but unsure
what kind works well and particularly how to power it through the
conduit run from the house.
Is direct burial coax any better or worse than LMR type or hardline
in pvc conduit? Soil is both sandy and rocky. The site is rural and
ups is preferred to truck shipments, so how do they ship hardline so
it does not get damaged or it is worth fooling with for this
installation?
Have never had any coax lightning arrestors, but was considering
putting them on the coax lines and control lines at the house single
point ground entry panel if I can find a reasonable cost solution and
ground the coaxes at the tower base. The house has both lightning
rods and a good perimeter grounding system.
ANY and ALL suggestions and comments will be sincerely appreciated as
will suggestions to keep the total costs of materials as low as
practical.
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