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[AMPS] parasitics

To: <amps@contesting.com>
Subject: [AMPS] parasitics
From: Peter_Chadwick@mitel.com (Peter Chadwick)
Date: Fri, 22 May 1998 14:50:48 +0100
Tom says:

>Actually the saturated emission current can be as high as 100 mA per 
>watt at normal operating temperatures of 1900k (the section on 
>Electron Emission, page 9-9, of Electronic Designers Handbook  by 
>Giacoletto).

>In pulse service, with 5.5 volts on the filament, Eimac supplied 
>data indicates the saturated current is  just over 10 amperes with 
>3000 volts of positive grid voltage and 5000 volts on the anode.

I got my figures from Terman. Even if I'm wrong, it's only a factor of 2. I
still find it hard to believe that you can get enough emission from that
filament to have currents large enough to bend grids or filaments, and I
still maintain that if the tube is oscillating, the current has to come from
the filament. Grids and plates have too low a work function for you to get
enough emission from them.

As far as 6146's are concerned, I don't have the curves here at work. Remind
me next month - I'm away next week at a CEPT meeting in Hungary.

73

Peter G3RZP


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