Michael Black wrote:
On Tue, 26 Jan 2010, Edmund H. Ramm wrote:

In cullen writes:

[...]
why is the tube type TR switch no longer made or used?

How did you arrive at the latter conclusion? I for one use an
E.F. Johnson T/R switch.

Have you been to your local ham store and looked over their selection
of T/R switches lately?

My local ham store doesn't have a good selection of anything other than
sealed appliance transceivers.

There are tube type TR switches made for military applications, but for
the most part they are too slow for modern signalling methods which is
why the PIN diode units are such a big deal.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."