Once I tried something similar to avoid using large zener diodes.
I didn't like very much the performance of several direct polarized diodes
in series to establish a voltage.
I had much better results using little bit more elegant circuit (my opinion)
that used a cheap 2N3055 (with heatsink) and a 7.5 V zener diode.
73,
Mauri I4JMY
-----Messaggio Originale-----
Da: measures <measures@vcnet.com>
A: Alek Petkovic <vk6apk@eon.net.au>; AMPS <amps@contesting.com>
Data invio: domenica 19 dicembre 1999 17.46
Oggetto: Re: [AMPS] 8877 bias
>
> >
> >Dick, throw those expensive zener diodes back in the junk box and use a
> >string of forward biased 1N5408's and then tap off the volts you need to
> >get the desired idle current.
> >
> >It's the cheapest and easiest method I know of. You can even wire them to
a
> >multi position switch to select the correct voltage.
> >
> Amen, Alek.
>
> - Rich..., 805.386.3734, www.vcnet.com/measures.
>
>
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