14 May '13, 7pm

Retrotechtacular: First laser transmitter built 50 years ago

Retrotechtacular: First laser transmitter built 50 years ago

They built their own helium-neon laser tube, which is shown on the right. The gentlemen involved were engineers at a company called Electro-Optical System (EOS) by day, and Ham radio enthusiasts by night. With the blessing of their employer they were able to ply their hobby skills using the glass blowing and optical resources from their work to get the laser up and running. With that side of things taken care of they turned to the receiving end. Using a telescope and a photomultipler they were able to pick up the beam of light at a distance of about 119 miles. The pinnacle of their achievement was modulating audio on the transmitter, and demodulating it with the receiver.

Full article: http://hackaday.com/2013/05/14/retrotechtacular-first-las...

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