Jim Lux wrote in
:

Dave Oldridge wrote:
"Kash J. Rangan" wrote in


If your antenna is balanced, it would probably be better to simply
split the ladder line onto the center conducters of two identical
short coaxes and then run ladder line inside to your tuner. If you
MUST ground the shields that's OK and you can use lightning arrestors
on both coaxes. But remember, no lighning arrestor is as good for
protecting equipment as a foot or two of air. Disconnecting during
thunderstorms is solid policy!


If you have a direct hit, a one foot air gap isn't necessarily going to
do you much good, unless the antenna end of the gap is on the ground
surface. (i.e. the wire going from where the coax ends to your
lightning dissipation ground has some non-zero inductance/resistance)

If you're worried about induced voltages from adjacent strikes, then a
good transient suppressor will help, but almost all suppressors have
"let through" voltage that is above the damage threshold for, say, a
FET front end. Depends on what your equipment sensitivity is.

Shorting the input of the radio and tying it to chassis ground.. that
WILL protect the radio.

I have been through some VERY violent storms. I always disconnected all
antenna and power leads from the radio. Outside arrestors will help keep
it out of the house but you need airspace to protect receiver front ends.
Also disconnect any ethernet runs.

Surge protection can only do so much. I learned the hard way about
disconnecting stuff. My neighbour across the street had a direct hit and
it danced across the phone lines into my equipment. I lost several
modems, a couple of ethernet cards and a monitor and considered myself
lucky that none of the computers was totalled. But my radios were
disconnected and unscathed.

Now the coast station I worked for had a direct hit on our Nautel 500khz
transmitter's tower. Blew out half the solid state final modules but the
damn thing kept right on ticking on the others!



--
Dave Oldridge+
ICQ 454777283
VA7CZ