You are correct Tom, your solution #1 does deal with the 'how to
successfully switch" the top hat. I have no issue with the fact that
solution #2 does provide dual frequency operation, but I don't think it
addresses how to successfully switch a top hat.
Still, one out of two isn't bad and #2 does solve the underlying problem of
dual frequency operation with a single structure.
From: Tom Rauch [mailto:firstname.lastname@example.org]
Sent: Thursday, July 19, 2001 7:44 AM
To: Tod Olson
Subject: RE: [TowerTalk] Top Hat Switch (mercury)
> I realize it is a lot harder to 'invent' a solution than to critique one,
> but in this case we really need some 'invention' more than critiquing at
> this point.
You may have missed it Tod, but two solutions were given and
1.) The suggestion was offered and a working example given (along
with a history of actual problems) of using a latching vacuum relay
or other vacuum relays. A 5kV or larger vacuum relay would have a
safe margin if power is kept below a kilowatt or so.
2.) The suggestion was offered of using a much more simple
solution of switching a base inductor or series capacitor in and out
and just leaving the hat connected in place (which would also be
more efficient electrically).
Those were two simple practical working solutions....especially
number 2 which would be the most simple system and the most
rugged and efficient electrically...and they were immediately
73, Tom W8JI
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