does need to amplify?You could use a divide-by-two attenuator (two 10k resistors) across the output to feed the ADC.
If output is in millivolts, then some amplification is desirable.does need to amplify?
Thank you.If output is in millivolts, then some amplification is desirable.
If you amplify it too much, you will destroy the ADC module.
Thank you ver muchThe ADC input will need to be DC-biased to about half the Arduino's supply voltage (assumed to be 5V), so that negative peaks of the audio signal don't drive the ADC input negative.
If the post #22 circuit is your radio tuner (albeit not a very good one), then you could ignore the 220n capacitor, connect the ADC input directly to the Q3 collector and connect a 10k resistor from Q3 collector to ground. The ADC input will thus be kept in the 0-4.5V range.
Incidentally, I think 560k is too low a value for the Q3 base bias resistor, unless Q3 has a very low current gain.
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