Optical Communications using Lasers

On Wednesday 20th March, the club hosted a very interesting talk and demonstration by Charles, G4DXP. Charles has been experimenting with line-of-sight transmission of audio, using lasers and pulse width modulation. He brought along his two home-built laser transceivers for members to play with, and gave us an explanation of how they work and how they are constructed.

Charles’ laser transceivers are based on a design by Ron Jones, K7RJ, and are elegant in their simplicity. In fact, most of the complexity in making the system work is in finding a reliable means for aligning the lasers over long distances, rather than in the electronics.

If you’re interested in trying to build something like this, always remember that even low power lasers can be hazardous. Never use a laser in a way that might endanger another person, or where the beam might come close to anyone’s face. Many countries have legal restrictions on the use of lasers, so do your research before buying or using any laser light sources.

Charles clearly loves his construction projects, as he also brought along a differential windlass that he’d built for members to have a play with.

On behalf of Colburn and Richmondshire District Amateur Radio Society, we’d like to extend our thanks to Charles for taking his time to come and visit us, and show off his various projects.