[ARC5] DARPA announces new program to improve vacuum tube performance----...

[WA5CAB--- via ARC5]

Sounds to me like they were trying to design EMP sensitive tubes.  

In a message dated 08/11/2015 18:08:43 PM Central Daylight Time, 
arc5 at mailman.qth.net writes: 
> Back in the mid 1980's IIRC the military made available a very large pot 
> of cash to do two things, to write software to do the electron ballistics 
> needed to design high performance vacuum tubes such as traveling wave tubes 
> magnetrons and gyrotrons, and to financially support college professors and 
> grad students to turn out new generation of tube designers.
> From what i can tell this has worked out well.  Since that was a 
> generation ago, this seems to me to be an effort to bring forth the next generation 
> of devices and designers.
> Similarly many years ago I heard of work modernizing vacuum device design 
> using semiconductor fabrication techniques.  For example use silicon 
> anisotropic etching to create a bed of nails, field emission electron emitter to 
> replace the filament thereby enabling high performance vacuum-electron 
> devices using more or less conventional semiconductor and nano-fabrication 
> techniques.
> Because the electron emitter-grid-plate spacing can be made very small and 
> very uniform these hypothetical devices would work with transistor type 
> operating voltages but- in the specific case I remember- much better RF 
> linearity and overload performance.
> So i have no idea wheeze all of this is going to go but I like the idea 
> that people are still thinking about designing and making useful devices that 
> employ electrons flowing in a vacuum
> bruce
> 
>       From: J Mcvey <ac2eu at yahoo.com>
> To: Bruce Long <coolbrucelong at yahoo.com>; Ian Wilson <
> ianmwilson73 at gmail.com>; Peter Eijlander (PA0PJE) <pa0pje at xs4all.nl> 
> Cc: "Arc5 at mailman.qth.net" <Arc5 at mailman.qth.net> 
> Sent: Tuesday, August 11, 2015 6:46 PM
> Subject: Re: [ARC5] DARPA announces new program to improve vacuum tube 
> performance----really!
>    
> You can't make this stuff up!
> 

Robert & Susan Downs - Houston
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