Topband: RFI - and lots of it

[Tom W8JI]

>I have driven copper ground rods in about ten years ago, then wrapped a 
>couple turns of #4 wire around the top and soldered that to the rod using 
>plumbers solder. These connections are as good today as the day I soldered 
>them. Plumbers solder works very well outdoors for me. I use it on 
>everything outdoors now.
>
> Dave, W5UN

80 year old broadcast radial systems are still good with silver solder 
connections. My 318ft tower gets whacked all the time and has silver 
soldered connections. They never melt. Even RF radials that augment the 
lightning ground, which are plumbers solder #16, do not get hurt.

The main reason NEC and other codes don't like solder is they don't trust 
people to know how to solder.

Of course the heat is I^2 R  times the time. It isn't just current, it is 
joules.  If the solder connection is good with low resistance, it will not 
get hot.

Also, there is no possible way a rod system could stay anywhere near zero 
volts in a strike. Almost all of the protection to equipment and the house 
itself is by the common point connection of things entering the house 
outside the house.

We certainly need the rods, but most of the protection comes from bonding of 
all things entering the dwelling. Very little of the protection inside the 
dwelling actually comes from the rods.

With a tower or tall structure likely to be hit, the structure ground can be 
a major player. That ground keeps strikes from raising the base voltage so 
much, and reduces common mode into the house grounds. It takes a pretty big 
ground system to not elevate in voltage in hits. A couple rods will not do 
it, even if they ohm just a few ohms at low frequencies.

73 Tom