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Wireless music transmission using lasers

  1. Jun 29, 2011 #1
    Hey all. I'm currently working on a project where I use a laser to transmit music playing from my iPod. The laser is hooked up to the iPod through a circuit, and there is a solar cell that the laser is pointed at. There are two wires coming from the solar cell that are connected to a stereo cable. My problem is that the sound coming from the speakers is very quiet, and I want to build an op-amp amplifier for the signal. I've searched for some stuff online but I keep getting a bunch of different things. Can I just basically use a single signal amplifier for each channel separately? Or do I have to build a more complex circuit to handle both of the channels? Thanks for your help.
  2. jcsd
  3. Jun 29, 2011 #2


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    Staff: Mentor

    Could you please show more details for the transmitting and receiving circuits that you are currently using? That will help a lot in determining what else you should add at the receiver.

    What power TX laser are you using, and how are you modulating its amplitude?
  4. Jun 30, 2011 #3
    Is your stereo cable connected directly to the speakers or does it go through an amplifier? If not you should try amplifying it before feeding it to the speakers.

    I don't know the frequency response of solar cells. I've never seen it specified so I assumed it wasn't very good. If you lack high frequencies you may consider using a photo diode instead of solar cells. A photo diode doesn't produce current like solar cells, but merely varies its resistance in response to varying light levels. A photo diode may also be more sensitive than solar cells but you still will need an amplifier.
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