Hi Guy,
I've asked this question and never received an answer. Maybe you or someone
else can help.
You wrote:
> If a *DC-blocking* arrestor is used at the house entrance, in addition to
> the ground of the shield, then the rest can be dealt with by a coax switch
> at the rig that grounds the incoming and leaves the HF rig disconnected.
Since lightning is a very high slew rate, and the bulk of the energy
is a rapidly time-varying voltage, it is not by any stretch of the
imagination dc. That's true even if it primarily flows in one direction.
With that in mind, exactly what does the capacitor do? What value
is it, and what is it's breakdown voltage?
I find it hard to understand what possible advantage a series cap
that has low reactance at RF (and probably limited voltage
breakdown) has when you consider the energy content of lightning.
I simply can't understand what major (or even minor) good the
capacitor can do unless someone connects a car battery to the
antenna, since lightning freely passes through high pass networks
that are much more selective than a simple series cap that
certainly must have a reactance of less than a few ohms on 1.8
MHz.
Also, if the capacitor charges and a gas discharge tube ahead of
the capacitor fires, the capacitor will extend the pulse length into
the rig while it discharges.
Anyone know how such a thing can help?
73, Tom W8JI
w8ji@contesting.com
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