To construct a Optical Transmitter and calculate its Output Power. Transmission of Signal through Fiber Optic Cable. To construct a Optical Receiver and calculate its output power. To study the Attenuation of Signal when transmitted from Transmitter to Receiver end. Instrument comprises of DC Power Supply 6VDC and 3VDC. Preamplifier stages consists of MIC (Microphone), Photodetector, Transistors (548) and biasing network Resistance and Capacitors. Power amplifier stages with impedance matching transformers (Driver Transformers, Transistors (8550) and biasing network of Resistances and Capacitors. Output section having LEDs (Light Emitting Diodes) and speaker. Fiber optic cable for transmission of signal.