This set of two circuits from the basis for a very simple light wave transmitter. A LASER beam is modulated and then aimed at a receiver that demodulates the signal and then presents the information voice, data, etc.. The whole thing is very easy to build and requires no specialized parts execpt for the LASER itself.
Part Total Qty. Description Substitutions
C1, C2 2 0.1uf Ceramic Disc Capacitor
C3 1 100uf 25V Electrolytic Capacitor
R1 1 100K Ohm 1/4W Resistor
R2 1 1M Ohm 1/4W Resistor
R3 1 10K Pot
Q1 1 NPN Phototransistor
U1 1 741 Op Amp
U2 1 LM386 Audio Amp
SPKR1 1 8 Ohm Speaker
T1 1 8 Ohm:2K Audio Transformer
MISC 1 Wire, Board, Knob For R3, LASER Tube and Power Supply
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