on 9/16/02 11:56 PM, Bill Hider (N3RR) at firstname.lastname@example.org wrote:
> Now, sometimes the tower is located so far from the shack (house) that the
> impedance in the coax shield
> over that long run (say several hundreds of feet) is so large that you'd
> think the lightning would dissapate before
> it got to your shack. Well, maybe it would and maybe it wouldn't. Why not
> be safe and provide a path for the lightning
> that YOU know is the one you want it to take? Add that measure of
> protection. In your case, 70 ' just doesn't come
> close to being far enough to ignore this, in my opinion.
This whole thing seems to be a bit of debate between people. To connect the
tower to the house ground or not to.
Most people I have talked to do not connect the tower ground to house
ground. The simplest reason, is you want to keep lightning strike energy
AWAY from the house. A big, long wire connecting 70 feet or more of length
is going to have a lot of inductance to lightning and won't do much good
The reason for tying electrical grounds together is for safety reasons as
you want all "ground" points to be at the same potential relative to the hot
wire in the electrical circuit. Otherwise, you can create major problems as
ground is not always "ground." Tying electrical grounds together fixes
This is a different purpose for the tower ground. In fact, I personally
think that keeping the ground separate is a very good thing as you want to
keep al lightning strike AWAY from your house electrical system.
The best protection of shack and equipment is as one person said to
disconnect everything. Sure, but it's not always practical. So the
alternative is to bite the bullet and drop the big bucks for surge
suppressors. One of the guys that helped me put up my tower told me in no
uncertain terms to do this. He said EVERY line coming from the tower going
into the house needs to be protected. The surge arrestors should be as
close to ground as possible and grounded right near the tower.
So yesterday I ponied up the big bucks and spent the money to get the
arrestors for every line. Cable Experts sells the ICE, Alpha Delta and
Polyphaser models. The ICE ones that I bought cost $40 to $46 each and look
to have a pretty good design.
NA9D (ex: KE9NA)
Life Member: ARRL, NRA
Member: AMSAT, DXCC
"A life lived in fear is a life half lived."