A laser beam is a interesting stuff that can be used in many project. One of the project is a simple laser communicator that is used to transmit the voice across the room. To build a simple laser communicator, we need audio output transformer, solar cell, small amplifier, radio battery pack and regular laser pointer. First, build the battery packet. It uses three AA battery, so the supply is about 4.4V. Then connect the battery packet with the laser pointer using a jumper. The one of wire is connected to the inside the regular pointer and the other is connected with the housing of regular pointer. So the laser pointer has a power. Here is the video:
Following the schematic, the audio output transformer is wired in line of the supply. And test the laser pointer still working. And the last connection of the transmitter is minicable with strip edge that attached to the audio output transformer. A small solar cell is used to build a receiver. And plug the radio cable with into the mini amplifier and connect the cable edge with the positive and negative wire of solar cell. To test this project, plug the transmitter into a transistor radio, then shoot the laser beam to the solar cell and see what happen. For a simple communicator, a transistor can be replaced with a microphone and the simple amplifier can be replaced with headphone.