Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Vacuum plasma windows and microwave accelerators
Date: Sep 20, 11:44 am
Poster: Jim Lux

On Sep 20, 11:44 am, Jim Lux wrote:

>However, the idea behind it is so obvious that I have trouble believing that someone didn't try and discard it 70 years ago. I have this photo from the Rad Lab at Cal (Berkeley) showing an early cyclotron firing a proton beam into the lab unimpeded. I had often wondered how the vacuum was able to be maintained inside the machine,


They shot the beam through a thin metallic window.... If the metal is thin enough, there are "gaping holes" between the atoms. Viz. the famous scattering experiments with gold leaf and alpha particles....
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>Some time ago, I found a TWT on ebay (12 ghz) which has been sitting around in the closet - perhaps just waiting for use in such applicaion.

You'll probably want to leave it in the closet... TWTs are notoriously difficult to adjust.. It also might be a cavity TWT and not a helix TWT. If you look at it there are probably lots of little pieces of magnets stuck to the tube, unless it is a solenoidal focussing type. I can think of a LOT of better things to spend your time on than trying to retrofit or modify a Ku-band TWT.
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