[Amps] Bias Zener Diodes In Parallel ?

[Steve Thompson]

>-----Original Message-----
>From: Radio WC6W <wc6w@juno.com>
>To: Douglas.R.Snowden@noaa.gov <Douglas.R.Snowden@noaa.gov>;
>amps@contesting.com <amps@contesting.com>
>Date: 17 July 2002 03:30
>Subject: Re: [Amps] Bias Zener Diodes In Parallel ?


>
>On Tue, 16 Jul 2002 15:45:42 -0400 "Douglas R Snowden"
><Douglas.R.Snowden@noaa.gov> writes:
>> That is what I was sort of thinking would happen.  Most of the
>> responses to my question are useful, but as usual you can't post
>> to this list without someone calling you stupid.
>>  Gee- at least I am doing some building unlike most hams.
>> I did not consider the fact that I was actually pushing the diodes.
>> The reason I am running several in series is because the amp is a
>> pair of
>> Russian GI7 triodes and needs more bias than usual  ~30volts
>> or so.  Sounds like I need to go with the xsistor/zener. Or a big
>> zener.
>>
>> Doug
>>
>
>Hi Doug,
>   If you need an adjustable bias, you might consider a TL431 (good to
>36V without additional parts) in conjunction with an appropriately
>heatsinked PNP power transistor (See either the National or TI
>databooks... or websites?).
You took the words out of my mouth, Marv. For a tested design using TL431,
you can see a circuit on G3SEK's website.

Steve