At 04:22 PM 1/5/2005, OM7ZZ, Jozef Urban wrote:
Yes Jim.
Little blue relays are used for switching of power vacuum relays. Principle
is same as used at serialy produced little brothers of this switches -
Double Ten and Double Six. Diagram of one port is available at:
http://www.microham.com/double%20ten%20switch%20features.html
Strip star cannot be at 50ohm because arms to unselected ports creates open
stubs and affects matching. Correct impedance is higher and has been
obtained experimentaly.
Of course.. but, in any case, they are transmission lines, as opposed to
casually chosen pieces of copper.
-70dB of isolation is a value who can be obtained relative easy with most of
relays suitables for RF switching if two are used in line. As Tom said, very
important is a grounding and proper layout.
73 Jozef OM7ZZ
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