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Wireless Transmitter Project Question

  1. Sep 2, 2007 #1
    I have a question regarding those pre-made wireless ic's that are ready to use that you buy in pairs (one is the transmitter unit and the other is a receiver unit). Now I want to use this in a project where I take a signal that is split from my cable television line and send this signal to the wireless transmitter and transmit to a receiver that is hooked up to another tv and receives the signal. The goal is to wirelessly broadcast the cable signal to the other tv. Now would a simple Analog to digital converter converting the cable signal with proper sampling feeding the transmitter be enough to transmit the signal? And likewise at the receiver end (after the signal is received) would the signal just need to go through a Digital to Analog converter to properly recover the television signal? Now I know that for proper wireless transmission I would need to encode the data in a way that minimizes data corruption over the wireless transmission. I am asking for opinions to see if this can work and perhaps gain more knowledge about this project that I am embarking on. Thanks all in advance.
    Last edited: Sep 2, 2007
  2. jcsd
  3. Sep 3, 2007 #2
  4. Sep 3, 2007 #3
    I know that there are some products out there, but they run on bands that are common, such as 2.4ghz or 900mhz which I know will interfere significantly with other wireless devices in my house. I was thinking of using a frequency not heavily used in the 300-800MHz range to minimize interference from the start. Part of this project for me is to learn a few things along the way and seeing if I can achieve the goal I am after.
    Last edited: Sep 3, 2007
  5. Sep 4, 2007 #4


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    Staff: Mentor

    The reason that they use those frequencies (and the transmit levels) is to fit within the FCC (US Federal Communications Commission) legal requirements for RF transmissions. You can't just make a transmitter at any old frequency and with any old spectrum shape that you want -- the chances are very high that you will interfere with some licensed transmissions, and that can be a bad thing. Just think if you started stepping on the local police and fire dispatch transmissions by accident -- how long do you think it would be before you got a knock on your door? Not long, believe me.

    So, your best and safest bet would be to start off using some pre-packaged transmission system, and learn what you can from that project. Then as you learn more (and maybe get your amateur radio license), you will start to understand the various band plans (the allocation of the RF spectrum by the FCC in the US, and other agencies in other countries), and you can see what projects you want to build next. For example, if you are a licensed HAM operator, you can build and operate TV links in the GHz region, but away from 2.4GHz WiFi and other bands. I don't know much about the operation, but I have seen it demonstrated before.

    Another option for you would be to get a pair of those TV-over-powerline units, and distribute the video that way.
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