One technique that may prove useful for lightning protection is suitable
bandpass filters for the RF lines. After all, most of the energy in a
lightning impulse is down in the 1 MHz range. Sure, there's energy out
quite a ways, but it's probably not enough to cook your front end.
Just speculating here... say you are looking at the higher bands (above
10MHz).. if you had a good high pass filter that could shunt low
frequency energy to the ground, that might do quite well. It would need
to be designed to take the voltage/current, but a high pass is basically
series C (easy to get for high voltage standoff) and shunt L (ditto)
say you put in a 50 ohms shunt Z at 1 MHz (which will be 500 ohms at 10
MHz).. without anything else in the circuit, you've already halved the
transient voltage at 1 MHz (because each leg will take half the current)
Put a series C in that's say, 500 ohms at 1 MHz.. that will reduce the
transient voltage by a factor of 10-11 (receiver z is 50 ohms)..
You'd need a matching network at the output to counteract all the stuff
you've done with the filter, but that's straightforward.
I'm not sure this is any easier or better than a traditional transient
suppressor, but maybe it's something to think about.
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