>Adjustable yes, but you don't have to
>change taps, just apply current through
>the string and it's voltage drop wanders
>all over the place.
Fwd drop varies little between 0.2A and 1A in a Si junction.
Henry Radio Co. amplifiers have used fwd-biased diodes for years. I
have used fwd biased diodes for over a decade in a TL-922 and a SB-220.
The ZSAC is virtually constant and I can set it if I change tubes.
>For voltage
>stability this is the worst way to
>provide bias.
So a resistor in the cathode would not be worse?
>TL-431, adjustable and
>rock solid voltage.
>Paul...
>> The problem with a 50w zener
>> is that its Vz is not adjustable. A
>> fwd-biased Si diode string
>> can be adjusted by changing taps.
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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