At 08:13 PM 12/19/99 +0800, you wrote:
>
>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
>
Alek, I'm using a 2N3055 pass transistor and a 1Watt zener diode, from a
January '81 Ham Radio Magazine project by K8RA, so not too bad to try new
voltages.
Thanks, Dick
>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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