In message <[email protected]>, Brian
Rogerson <[email protected]> writes

I'm sorry, I could not resist.  73, Brian

At 15:55 15/03/01 +0100, you wrote:

With nostalgic smile I read the many mails about EF50 and other tubes that I
used in the "tube-times" of my ham-life.
Here some electrical data of it:
(source: Röhren-Taschen-Tabelle Franzis-Verlag München 1964)

The tube was used for HF- and wideband-amplification up to 50MHz. The
amplification could be regulated by varying the negative voltage at grid 3 -
says the book. This seems a little unbelievable to me, because mostly a
variable voltage at grid1 was used.

That's the normal method, but when used in the H2S equipment, after the
Tx pulse the Rx was used in high gain mode, with a few plus volts on the
g3 to catch the first ground return.

Mike
--
M.J.Powell