I am planning to make an experimental communications system.
I will use a high power LED (≈3watts) Amplitude Modulated with a sound signal and eventually Pulse modulated with digital data for the transmitter.
And a focused lens with some sort of photo detector (PhotoTransistor, PhotoDiode, PhotoResistor, Plain old LED etc.) for the receiver.
To amplify the small AM signal from the photo detector, I am looking at microphone preamp circuits. How much gain will I need to amplify this to around MP3 player output?
(A high impedance output is fine for I will be feeding it into another amplifier stage, I just want the approximate voltage of an MP3 player output)