Warren,
Your query will undoubtedly bring forth many responses from the TowerTalk
group. The design of your 'bulkhead' will need depend upon your individual
needs, and the physical constraints of your new home. I can give you a few
ideas that have worked for me.
My station is located on the second floor of a Colonial-Style home in Maine.
To keep the bulkhead neat and somewhat out-of-sight, I built a shallow
cabinet into the outside wall, between the 2X6 studs. Inside the cabinet is
a Single-Point-Ground-Panel (SPGP) that I purchased from a Polyphaser
dealer. The SPGP is a thick sheet of copper fastened to a fiber-board
support panel that spans the distance of two studs. All of the impulse
protection devices are fastened to the copper plate. You will need
protection devices for each coaxial cable that will pass through the wall,
into the shack. You will also need a separate protection device for each
rotator cable that you plan to install.
If you are going to place your bulkhead panel at the foundation level, you
can conceal the cables in PVC conduit, and plant some shrubbery to hide the
cable box. In my case, I created a dummy 'trunk' that runs vertically from
the soffits to the soil surface level. All of the coax and rotator cables
run inside the 'trunk'. In order to provide a ground connection with the
least inductance, I ran a length of 8-inch-wide solid copper 'flashing'
inside the 'trunk', from the second floor to the bottom of the 'trunk'.
Copper flashing is available from roofing companies, and 'Big-Box' stores
like Home Depot, or their local competitors. Use copper strapping to make
your inter-connects. Polyphaser sells 1-1/2 inch and wider copper strapping
for this purpose.
The actual grounding method is open to discussion (and heated argument).
Depending upon the soil conductivity, there are many ways available for you
to install the ground SYSTEM. I emphasized the word SYSTEM, since a good
ground consists of multiple, interconnected ground 'rods' or other approved
buried conductors. Go to: http://www.lyncole.com and http://www/harger.com
to see several types of chemical grounding methods. I have used many of
these in commercial installations. They work very well in rocky terrain..!
Also, go to http://www.polyphaser.com and
http://www.arraysolutions.com/Products/ice/ to find most of the hardware
necessary for a reliable grounding system. Impulse protectors are available
with most of the commonly used RF connectors, such as BNC, UHF, N, etc.
Many suppliers of Polyphaser products also sell an excellent book (about
$20) that will provide most of the information that you will need to design
a good ground SYSTEM.
If your installation is on a lower floor, or in the basement, you can
install the cables through the walls and make your entry below the soil
surface. Have the contractor embed some lengths of conduit through the
basement wall and cap them until you need to run your cables. You can use
PVC, or metal for the 'feed-throughs'. Be sure to angle the 'feed-throughs'
downward toward the outside to allow drainage. After the cables are
installed, stuff the openings with insulation, sealant, and finish off the
outer ends with copper or stainless-steel wool, not ordinary steel wool.
Copper wool can be obtained through boating supply dealers. S-S wool is a
bit more difficult to find, but either Copper or S-S wool will prevent the
little critters from burrowing through the 'feed-through'.
In addition, be sure to make your 'feed-throughs' from 4-inch or larger
tubing. This will allow the future installation of additional cables with
their connectors already installed.
Now that I've opened the proverbial 'can-of-worms', I'll sit back and watch
the 'shot and shell' fly overhead..! BTW, who has the license...? You or
your new wife..? (commence flaming NOW..!)
vy 73 de Larry - W1GOR
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of
WarrenWolff@aol.com
Sent: Sunday, December 14, 2003 11:16
To: towertalk@contesting.com
Subject: [TowerTalk] Bulkhead Source
Greetings!!
I am a year off from building my new home at Lake Havasu City. I expect to
have a 70 foot crank up and a 55 foot crank up. In designing the layout, I
have come to the "bulkhead" for feedlines and control cables from the shack
to
the outside.
Am I stuck with designing my own or is there a source for reasonably priced
bulkheads? I am sure I could do my own, but my new wife is going to demand
high professionalism.
Warren
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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