30-10-2014, 02:57 PM
Voice over by using a laser transmitter and receiver, you can communicate with your neighbors in wireless. Replace the RF signal transmitters-receivers by simple circuits, light is used as a circuit. If carrier receives the light-sensing device is precisely towards the transmitter circuit for laser in laser beam welding torch can light up to 500 meters. By use of fiber to avoid direct interaction between laser and light sensing devices.
Transmitter circuit includes: condenser microphone transistor
Then an amplifier stage. The POTMETER It's gain and amplifier stage. The AF output is coupled to another with the help of the transistor's base electrode and a modulated laser beam control.
Receiver circuit (Figure 2) using NPN transistors as followed by a two-stage transistor preamplifier and audio power amplifier. The receiver does not require any complex alignment of optical sensors.
Just keep long-distance transmitter's photosensitive transistor laser tube and adjust the volume control of the crystal clear sound.
We were able to avoid the 50Hz of AC noise of speakers, remain photosensitive transistor tube away from the AC source, such as bulbs. The reflection of the Sun's light, but does not cause any problems. However, the sensor is not directly facing the Sun.
Reference: https://seminarproject.net/Thread-laser-...z3HcQQ97oJ