Why would there be smoke coming out when the current supplied to the base of the PNP is well under 100mA?
As it stands, I can pick up the audio through a 4.5W, 8 ohm speaker by connecting it in series with a 220uF capacitor. I then connect that to the point where the emitters of both transistors meet. The other end is grounded.
So as long as I can hear something at full volume through the speaker, I should be able to obtain the proper logic levels.
Audioguru, your resistor-capacitor values did NOT help. In fact, they made my LED stay on forever at full brightness. Still, there is NO SMOKE :wink:
Maybe I need more diodes.
The only other thing I can think of off the top of my head is to somehow make an ADC circuit.
I think the impedance is 27K because the last audio amplifier stage output before this circuit is connected to a 27K pull-up resistor and the collector of the NPN.
Should I enforce voltage division alot more?
because it seems that when I create more voltage dividers, Audioguru's circuit works better for the logic gates, but when I use the speaker, the results are worse. At least the volume is alot lower.