All:
 Original article from: Wayne Sarosi 
 Reposted by Rob Dennis,Moderator HAM_TECH,for use of the FIDO HAM_TECH echo.
  THIS POST/SERIES NOT TO BE USED IN ANY CDROM COMPILATIONS FOR COMMERCIAL
 SALE WITHOUT EXPRESS WRITTEN PERMISSION OF ORIGINAL AUTHOR(S) OF THIS POST.
               ALL AND ANY COPYRIGHTS RETAINED BY AUTHOR(S).
SUBJECT: Shack Designs - part 4B
RF distribution
 OOPS. Make that 14 coaxial lines. I noticed I typed in the wrong amount.
 We can drop the UHF TV line as discussed earlier.
 Now we have 13 coaxial lines to look at. Of these there are four receive 
nly
coaxial lines; 500-1300 MHz LPA,Discone,49 MHz dipole,and the FM band dipole.
 Generally,I run these to their respective receivers and let it go at that.
 Only if I know there is going to be a serious lightning storm will I
disconnect them. Three are under the big LPDA. The 500-1300 LPA is near the
top of the tower and usually this coax line is disconnected when not in use.
 I will explain how these lines are electrically secured.
 That leaves us with 9 coaxial lines used for transceive.
 Each of these enters the shack and goes to the RF closet. This closet can be
an RF panel, a gagle of coaxial lines hanging be the wall,a tangled mess,but
it doesn't really matter except that these lines come in at a common point.
 At this point we will also have the groundwire terminate in the shack.
 Why? Because the not-in-use coaxial lines will be attached to the 
roundwire.
 This creates at two-fold safety system.
 First, it protects the shack and operator from lightning using the safety 
ap
I'll explain later.
 Second,the antennas and coaxial cable are `safed' to ground and RFI is
contained via open coaxial lines.
 The safety cap:
 If you use PL-259s or N connectors you will need a bullet (F-F) and a Male
connector to match your connector use.
 Using this male connector,solder a shorting wire from the center pin to the
sleeve. Attach this connector to the bullet. Now you have a safety cap for a
coaxial cable.
 When this safety cap is clipped to the groundwire,the centerpin and shield
are grounded directly to the groundwire. There is no electrical path to your
rigs via the coax.
LABELS:
 Labels are a must in a multi-cable input station. Ever try to work 20m with
a VHF discone and not discover it until you are ready to close shop?
 Or have your HF vertical attached to your VHF Packet?
 Funny as it sounds, you probably say it was a bad connector instead of the
wrong antenna,I sure would.
 I use a simple labeling system. For the LPDA, I label it 'LPDA'.
 For the Discone it's 'Discone'. For the 2m SSB Yagi it's '2M SSB'.
 I use two inch wrap-around, covered labels. I replace them every three years
or as changes are made. (I've never reached the three year mark yet. Typical
Amateur. )
BUNDLING:
 As the cables leave antennas,run them at right angles as much as possible.
 At rotors be sure to leave twist loops and at feeds to the antennas use drip
loops. Run your cables on one leg of the tower and be sure not to run them
across areas that you normally step on when climbing the tower.
 At about 6 to 8 feet, right angle the cable bundle to the shack. Use a drip
loop before entering the shackand keep the bundle high as possible.
 This keeps the dog,kids and curious pokers out of touch with the cables.
 I usually slap a `HIGH VOLTAGE' label on the input to the shack.
 It's amazing how it works.
 Enter your bundle; leave about four feet of the bundle intact before 
reaking
it out into it's separate cable runs.
 Secure the bundle to the wall at the point of break out.
 NOTE: ALWAYS run the Ground Wire separate with a separate entry point and
run it as LOW and as DIRECT to the central ground point as possible.
 NEVER run the ground at hard right angles vertically.
DISTRIBUTION:
 This area is mostly dependent on your shack design. Keep away from RF cable
over AC lines. Keep RF from Data Lines as much as possible.
 Distribution should be clean and right angled as much as possible to
eliminate RFI.
 Take care with connectors,make them clean,correct and strong.
 NEVER coat the connector threads or center pin with silicone grease,it
is NON-conductive.
-WS
--- GoldED 2.42.G1219
---------------