From: John Woodgate
Subject: Re: NEED ADVICE: Vacuum tube grid current?
Date: Wed, 8 Jan 2003 11:57:16 +0000
Organization: JMWA Electronics Consultancy
Reply-To: John Woodgate
NNTP-Posting-Date: Wed, 8 Jan 2003 13:14:41 +0000 (UTC)
X-Newsreader: Turnpike (32) Version 4.01 <5Z8C9wtxbnpWyFnyfFzqmVF739>
I read in sci.electronics.design that Ross wrote (in
) about 'NEED ADVICE:
Vacuum tube grid current?', on Tue, 7 Jan 2003:
>I'm doing this project for school that involves a complete mathematical
>analysis of this receiver that I built. The detector (it's a
>regenerative design) uses a grid-leak method on a 6GH8A pentode.
>Let me hasten to say that I'm not asking you for all that! I've got it
>almost done (I hope) except I need a model for the control grid current.
>It's a function of Vg and Vp, I beleive. And no, I'm not using SPICE- I
>find the tailoring of all those fitting parameters more confusing than
>applying Kirchoff ad finitum to the circuit.
>Thank you very much for your time.
The source for arcane lore on vacuum tubes is 'Radio(tron)* Designer's
Handbook, F Langford Smith. The 1998 reprinted edition is ISBN 0 7506
* (tron) was included for the original Australian and the US editions.
Chapter 2, section 8 probably has everything you need, and then some.
You may need to dig around to find if the 6GH8A is similar to one of the
older types for which data is given in the examples.
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
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