[AMPS] AB1 vs AB2

[w8jitom@postoffice.worldnet.att.net (w8jitom@postoffice.worldnet.att.net)]

> To:            amps@contesting.com
> From:          "Ian White, G3SEK" <G3SEK@ifwtech.demon.co.uk>
> Subject:       Re: [AMPS] AB1 vs AB2
To: <amps@contesting.com>
> Date:          Wed, 11 Jun 97 19:54:52 +0000

> Zeners are a little better, but the dynamic resistances of higher-
> voltage zeners are not as low as the more familiar 6-12V diodes. 
> You'd be very lucky to get below 200 ohms for a 350V string of zeners.

Zeners are OK for class C PA's, but I'd consider some sort of active 
amplifier working against a stable reference driving a shunt 
regulator. By then way, most zeners cross zero temp coef at about  5 
volts. At several hundred volts they move around a lot as 
temperature changes.

73, Tom W8JI 

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