I have read that these old knife switches have very poor RF insulation
qualities. Perhaps this effect is frequency and/or power sensitive (for
want of better terminology) to some extent.
Doc.
"Holger 'Geri' Kinzel, DK8KW" wrote:
Tom, G3OLB:
>Years ago I remember my grandfather having a wireless aerial (as it was
>known then) down his garden which came through an insulator in the
>window frame and was connected to a ceramic knife switch on the window-
>sill. This allowed changeover of the aerial from the wireless to earth
>during thunder storms. Does anyone know of a source of such switches
>these days?
... have a look at
http://www.surplussales.com/Antennas/Antennas-4.html
... the second item is similar to the switch that I use to ground my
umbrella antenna whenever not in use. Is this the kind of switch you are
looking for?
Best 73
Geri, DK8KW (W1KW)
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