From: John Woodgate
Subject: Re: In Need of a 50-KV Electron-Gun
Date: Sun, 27 Oct 2002 07:28:36 +0000
Organization: JMWA Electronics Consultancy
Reply-To: John Woodgate
NNTP-Posting-Date: Sun, 27 Oct 2002 09:04:19 +0000 (UTC)
X-Newsreader: Turnpike (32) Version 4.01 <5Z8C9wtxbnpWyFnyfFzqmVF739>
I read in sci.electronics.design that Jim Adney
wrote (in ) about 'In Need
of a 50-KV Electron-Gun', on Sat, 26 Oct 2002:
>It really doesn't matter what kind of grids you put along the way, as
>whatever acceleration is necessary will occur no matter if the
>distance is small.
Yes, it does matter what sort of grid you use. That's why the suppressor
grid of a pentode valve doesn't stop the electrons hitting the
anode/plate. It is usually a very open spiral of wire, so that most of
the electrons 'feel' only a weak field from it and are not slowed down
It 'suppresses' the secondary electrons emitted from the anode because
they move much more slowly.
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
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