If you run them into conduit you need to ground them to the conduit or they will arc. It is best to ground all cables to the base of the tower and also at the shack entrance where protective devices
Copper tubing is a waste of money. Buy copper strap instead. You get much more surface area for your money. Copper tubing has one whole side (the inside) that is wasted. Copper strap makes use of bo
Hi JC, I think I understand what you are saying but some may not. A copper tube doesn't have better conduction at higher frequencies than a solid conductor just because the frequency is increased. Bu
If the shield of a coax cable carries a lightning strike about half of the energy gets transferred to the center conductor of the cable and propagates down the cable just like a radio signal would.
If the current is DC it will flow anywhere in the copper block. If it is AC current it will be forced to the outer surface of the block. Eddy currents will cancel the current around the hole and at
I don't think resonance would be a problem with the frequencies involved with lightning. If your ground lead is that long the inductance will be off the chart already. Although inductance may be the
Jim, What common mode are you talking about? Coax carrying current usually happens on a tower when one end of the coax is at the top and the other end is at the bottom with lightning striking at the
It is far from common mode. The voltage difference between the top of a tower and the bottom of it can be many thousand volts due to its inductance. A coax cable hung on the tower, even if grounded
I suppose I could say the same Jim. 73 Gary K4FMX _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http
Bill, You need not go to the bother of flattening the hardline. You have the same surface area with it round or flattened. 73 Gary K4FMX _______________________________________________ _____________
If the strands touch each other or not that does not change the total resistance of the cable. This does not change the resistance of the cable. It will not cause some strands to vaporize. It can ch
So as not to confuse anyone about "single point ground systems" it is important to understand that it is a common point that all equipment, power, antenna leads, phone lines etc. are bonded at. Whil
Hi John, The best way to install a "single point ground system" is to have all cables; antenna, phone, power etc. come into the house at one place and bonded there. However it is not always possible
Having a mast, or anything else, grounded or not grounded has very little to do with the chances of it being struck by lightning. As a matter of fact a grounded mast may be slightly more prone to tak
You need a hipot tester. 73 Gary K4FMX _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.con
When I mentioned earlier that a hi-pot tester should be used I had forgotten that the ICE units have a coil to ground. A hi-pot tester would do no good there. With Polyphaser units there is no coil t
Some years ago Polyphaser was working to develop a "dynamic ground impedance tester". He tried using a large ball several feet in diameter as a reference. It worked somewhat but the problem was too m
They use DC to prevent skin effect loss at AC. 73 Gary K4FMX _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contestin
We had a field like that on our farm. One field would never grow things worth a darn while the others seemed to do well. No HT lines within miles though. 73 Gary K4FMX _______________________________
Just think about the power difference to 100 watts that normally gets used. 2 watts is only 17 db down. If a signal is around 20 over 9 with 100 watts it will still be a little over S9 with 2 watts.