Hello:
I've been monitoring TT since this past Sept. and really enjoy the
discussions. I am awaiting delivery of my first tower in 25 years - a UST
HDX570 - and have LOTS of questions. I went to Dayton for the first time
this year and garnered lots of info including a Polyphaser manual. Recently
there was a discussion about cable feed through and lightning protection.
I've gone through all the TT archives and some very nice web sites, which
have been all helpful, but nothing really addresses the problems of
grounding and lightning protection when your shack is on the 2nd floor.
I've tried some direct emailing and some have been most helpful - thanks
particularly to Dick Flanagan.
Here's my setup : when we built our home, which sits on 30 acres of rolling
hills, the XYL agreed to develop over the garage where I could have a
dedicated ham shack. Now, some mistakes were made (no, really!) and the
contractor's idea was to have a safety ground consisting of large gauge
copper wire which passes down behind the brick veneer to a ground rod. The
rigs are attached to copper straps behind the desk and then attach to the
ground rod which is virtually underneath me. Additionally, a utility box was
placed in the drywall where two 1 inch electrical conduits went down behind
the brick, under the drive, and out to the proposed tower site (about 100 ft
away). Actually, plans are for two towers to include a smaller R25 tower for
satellite antennas. The driveway has not been poured yet and consists of
simply 33C rock for now - so I can dig into it now if I choose. Now
obviously there are limited amounts of cable that can be introduced into
these small conduits. I was thinking about running something like LMR400 and
rotor control cabling down each conduit where I can then attach remote
antenna switches. Then after reading the interesting posts on lightnig
protection I started to worry. I may be able to dig up the ground rod under
me so as to attach a radial which would then connect to the tower ground
system - but where should the SPG be ? Conventional wisdom says outside the
shack. I have a window which faces the proposed tower. I seem to remember a
window unit that could act as a SPG and then direct ground from there. I
would have to forget using the present conduits and go from the window box
with new larger PVC conduit. I also need to consider feeding wire antennas
for 80 and 160 meters. Oh, the antennas on the tower - Force 12 Mag 620/340
and 4BA separated by about 9 feet on a 20 foot Chrom-molly mast. The wind
figure for this county (which seems to come up alot on this reflector) is 70
MPH.
What say you, TT'ers. What is the best solution to a second floor shack ?
Comments and criticism on any and all of this would be appreciated.
James C. Hall, MD
WB4YDL
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