TF3KX schreef:
Hello:

I am contemplating constructing an antenna where a center-fed HALF WAVE
will be bent in a loop, only to be isolated at the almost-touching ends
by a relay or some other means of a remotely controlled switch. When
the relay contacts are open I will have very high RF voltages between
the contacts, probably "a few KV" or even more. Are there any
suggestions on where I could find a relay, if any, for this? Or any
other means for doing this? An additional constraint is that the
switching device needs to be light and small (say, 1-2 oz or 20-50
grams). Some ideas I have come up with a

- A small vacuum relay (supplier, type?).
- A home-made relay, providing more contact spacing than usually
available.
- A DC-motor (toy-type) driven mechanism to open and close contacts.
- A mercury switch that could be tilted to make or break the contacts.
- A string-operated switch to open and close the contacts (would run up
the antenna mast).

Any comments or suggestions?

73 - Kristinn, TF3KX


IMHO two high power relays would be an option, about 10 inches seperated
from each other.

For example Titanex (www.titanex.de) sells good High Power Ceramics
Relais for this purpose:
http://www.titanex.de/frames/acc.html#UB6-9 (HPRL) with power handling
of 5 kW each.

Palstar in the US use high power relais in some of theire antenna
tuners, but those relays are not ceramic.

Good luck!


--

73,
Hans Remeeus (PA1HR)
http://www.remeeus.eu
Communication is about people, the rest is technology.