transmitting sound using laser to 1 mile

[ahmed fathi]

Hello,

I am an engineering student , beginner in electronics , and I wanted to ask :

If I try to make a transmission of sound using laser over 1 mile in the darkness, and about 50 meters in the light , how much would something like that cost , and where to start learning about what to do ?!

to clarify : it is some kind of competition between students , ending in about two weeks , between teams not individuals

thanks in advance

 

[Usama Siddiqui]

yes its possible and is quite cheap aswell using just a laser light and phototransistor some transistors (for amplification) or an ic would be,over all it will be less then 500pkr, and maybe this would help you https://www.instructables.com/id/Send-Music-over-a-Laser-Beam/

 

[chuckey]

If we are to believe the article in the above link, then the kit should be less then £100 UK. The problem I see is actually keeping the laser spot pointing at the target, because at a mile you will not be able to see it , even in the dark from the transmitting end. A large parabolic mirror at the receiving end will give you a bigger target to shoot at, because any temperature differentials down your path will cause the beam to deflect as will any breeze blowing on the transmitter.
I would go for a PWM link, only costs a few £s more and gives you 100 X sensitivity.
Frank