most modern tranceivers do have enough protection on the rx line to
bleed off that charge, either in the form of diodes or just from the
input filters. this charge can build up to quite high levels, i have
frequently heard arcing in b&w switches from by 160m antennas and it
will arc from the center conductor to shell of a pl-259 if the coax
is disconnected. a lightning arrester would probably not protect
against this build up, but a small inductor to ground or a shorted
stub of the type used for harmonic filtering does a nice job.
i would be surprised if it could take out a tube type front end, but
i did once have a cheap cb front end blown out from rain static on
a mobile.
WBH3@chrysler.com wrote:
>
> I have from time to time experienced hearing noise in my receivers caused
> by rain hitting the antenna. I believe this is called "shot" noise. A
> friend of mine, N1GIQ, has mentioned to me that I should really try to
> protect the front ends of a couple of my Collins 75S-3 receivers and also
> my Icom 765 from this noise and ESPECIALLY from what he calls "snow"
> static/noise. Now I have done some checking and I cannot find any
> printed material which alludes to this snow static. Apparently, it can
> build up quite a charge and if it would wipe out the front end on a
> tube-type receiver I can imagine what it does to a transistorized receiver.
> I guess that I have just been lucky these 47 years that I've been a
> ham and haven't been nailed by "snow" static. Has anyone else come across
> this phenomenon and should I really be worried. Would a lightning arrestor
> provide protection against this? I don't think so. I've always thought
> that back to back diodes across the antenna terminals was a pretty good
> precaution, but don't know how to do this with a transciever. Your
> comments would be welcome.
>
> Regards,
> Bill Haselmire WX8S
> Highland MI
> wbh3@chrysler.com
>
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David Robbins K1TTT (ex KY1H)
k1ttt@berkshire.net or robbins@berkshire.net
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