[ARC5] Reverse engineeing the BC 456

[J Mcvey]

Good news,
I put a 5V zener in parallel with the cap, increased the resistor value to 39K, added a  BE resistor to adjust  the bias and it works with an electret ( yes ELECTRET)  mike too!
Thermal stability is poor, though. It's a little too simple...However if the q point is set at 12V it has a lot of leeway to drift with no big consequence to the audio, since the  P-P swing is < 5V anyway.
 

    On Monday, March 20, 2017 2:44 PM, "arc5 at ix.netcom.com" <arc5 at ix.netcom.com> wrote:
 

  The simple diagram is not at electric. The simple diagram shows a "bad" carbon element which is Amplified by the transistor.  I did not use an electric in any of these experiments. All of them were low output carbon elements.
 Sent from my Ain't Smart Phone.


   
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