Make a Simple Laser CommunicatorShow Video Details ↓ Kip Kay: Hello and welcome to another weekend project from Make Magazine I am Kip Kay. If you've seen any of my other videos you know that I love lasers. Red, green, blue, there's just something intriguing about laser beams and there's also a wealth of projects out there. For instance did you know that you can transmit your voice across the room on the beam of a laser? Well, we're going to do just that on today's weekend project as we build a simple laser communicator. [music] [music] … … … You can find the simple laser communicator by Simon Quellen Field in Make volume sixteen. To build this fun project you'll need and audio output transformer, a solar cell, a small amplifier, a radio, a battery pack and of course a regular old laser pointer. First we'll need to build a battery pack for our laser pointer and I have a four double A battery pack but we only need three double As so we need to run a jumper to complete the circuit for the last battery and that will give us all four and a half volts that we need. Now we are going to disassemble the laser pointer by taking out the button cell batteries that come with it and then running jumpers. One will go to the contact inside the laser pointer and the other will attach to the actual housing of the laser pointer. And then we'll hook those up to our new four and a half volt battery pack and test it out and we have power on our laser pointer. Now following this schematic along with this video you'll take the audio output transformer and wire that inline with our power supply and double check and make sure that the laser pointer is still working. Now the last connection for our transmitter is going to be a mini cable with stripped ends and that will be attached also to the audio output transformer which completes the transmitter end of our simple laser communicator. To build the receiver we need a small solar cell. This one maxes out at only a half a volt but it will do the job for us. Now just a word of caution, these little solar cells are very delicate so handle them with care or they'll snap in a heartbeat. Now we're going to plug an audio cable into our mini amplifier and that audio cable will have stripped ends which we'll attach to the positive and negative wires that we soldered to the solar cell. And now it's time to test it out. So we're going to use a little transistor radio and we're going to plug our connector from our transmitter into the radio and set everything up and see how it works. Now what happens is the audio signal varies the power that's going to the laser so that its brightness changes. At the receiving end, the solar cell converts the oscillating light signal back into the original sound. Well now that we've transmitted a radio signal across the room from our laser pointer to our solar cell, it's easy enough to turn this into a simple communicator by replacing the speaker on the solar cell end with a set of headphones or an ear plug and replacing the radio on the transmitting end with a microphone. So that's how you transmit a radio signal across the room in spy mode. And we'll see you next week with another project you can build over the weekend. [music] … [silence] |