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.
73 de Alek. VK6APK
At 07:17 PM 18-12-99 -0500, Dick wrote:
>Reflectories,
> I have two 8877 amps, I built them with 12V zener diodes for bias,
>they both idle at abt 40-50 ma. I changed one to 9.1V still 40-50 ma. If i
>eliminate it, the idle current is 275 ma. (I'm running 3KV). I next want to
>try 5.1V, but have never seen an amp article use such a low voltage. what
>are others using for bias and what resting current? Thanks, Dick
>
>Amp photos:
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