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  • Raspberry Pi FM Transmitter

    From Choco@VERT/DMINE to All on Tue May 19 12:38:35 2015
    Hello.

    I have a question reguarding a method I found to turn the Raspberry Pi Microcomputer into a FM Transmitter.

    In this tutorial, it is farily easy. I will be complying wih part 15 of FCC rules so I do not need to pay a licence fee.That is, 200 feet radius of transmission, between the bandwidths of 88 and 108 FM. However, I have found people who claim that do to the software's odd method of creating the transmission, it can broadcast on multiple frequencies at once, going over 108 and under 88. My antena will be a small one, and will probably honestly only exceed 100 feet in broadcast radius, let alone 200. If I were to inadventandly broadcast to somthing like 580FM, how muchtrouble could I get in? I am only thinking about it, honestly. I'm not sure if I will follow through. The raspberry Pi is capable of transmitting from 1 to 5000 FM, according to
    what I read. Will I get into trouble if I broadast?


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  • From echicken@VERT/ECBBS to Choco on Wed May 20 10:34:09 2015
    Re: Raspberry Pi FM Transmitter
    By: Choco to All on Tue May 19 2015 12:38:35

    of transmission, between the bandwidths of 88 and 108 FM. However, I have found people who claim that do to the software's odd method of creating the transmission, it can broadcast on multiple frequencies at once, going over 108 and under 88. My antena will be a small one, and will probably

    Presumably they're talking about harmonics.

    honestly only exceed 100 feet in broadcast radius, let alone 200. If I were to inadventandly broadcast to somthing like 580FM, how muchtrouble could I get in? I am only thinking about it, honestly. I'm not sure if I

    If you really want to be safe, adding a bandpass filter between your transmitter and your antenna will help to suppress harmonics. (There's plenty of info out there on how to build such a thing.)

    Realistically, you'll be transmitting with very little power, and the harmonics shouldn't be a problem for anyone. It's unlikely that you'd get into any trouble. But don't let that stop you from improving upon what sounds like a dirty transmitter.

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    echicken
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