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How to transmit composite video

  1. Jul 18, 2014 #1
    Can I use a 315MHz transmitter module to send a composite video signal to another reciever module?
     
  2. jcsd
  3. Jul 18, 2014 #2

    Baluncore

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    Bandwidth of a 315 MHz module is probably too narrow for video signals.
    315 MHz is usually used for lower data rate digital links.
     
  4. Jul 19, 2014 #3

    davenn

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    HI Tesladude

    I dint know if you realise but there are dozens of AV sender and receiver modules out there
    that a licence isn't required for ... here's one eBay example.....
    http://www.ebay.com.au/itm/like/121370720997?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=107


    That one is 200mW quite high power. I don't know what country you are in or what the legal power limits are before a licence would be needed.

    A composite video signal requires approx. 7MHz bandwidth

    I would strongly suggest you experiment with these styles of modules as you really don't want to
    be playing with RF electronics unless you have the skills and test equipment

    cheers
    Dave
     
  5. Jul 19, 2014 #4

    sophiecentaur

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    PAL and NTSC get away with about 7MHz.
     
  6. Jul 19, 2014 #5

    Baluncore

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    Which is the problem. The SAW filters used in 315MHz modules are usually only 600 kHz wide.

    http://www.maximintegrated.com/en/app-notes/index.mvp/id/3587
     
  7. Jul 19, 2014 #6

    sophiecentaur

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  8. Jul 19, 2014 #7

    Baluncore

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    Then they fail to meet the FCC specifications in USA where 315 MHz ±394kHz is available for compliant devices.

    Digital FSK has some immunity to interference, analogue ASK does not.
    On 315 MHz the AV would be sensitive to interference from many compliant devices.

    Chinese manufacturers are now flooding the world market with non-compliant broadband products.
    There are frequency allocations available for AV distribution in the USA that are more appropriate than 315 MHz.
    I don't think PF should encourage anarchy in the spectrum.
     
  9. Jul 19, 2014 #8

    jim hardy

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    The units Dave linked appear to be not 315 mhz but 5.8ghz

    any relief there ?
     
  10. Jul 19, 2014 #9

    davenn

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    yeah that was on purpose, Jim :smile:
    was trying to get Tesladude as far away as possible from the 315 and 433MHz bands

    mainly cuz of the masses of available 2.4 and 5.8 GHz AV senders and receivers available at small prices :)

    Dave
     
  11. Jul 19, 2014 #10

    Baluncore

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    Sorry, I missed that link.
    The answer is NO. Do not use 315 MHz or 433 MHz for video.
    As others have pointed out, there are better bands allocated for short range video transmission.

    That is very wise.
     
  12. Jul 20, 2014 #11

    sophiecentaur

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    Absolutely; I couldn't agree more. Things are getting slacker and slacker as it is.
     
  13. Jul 22, 2014 #12
    i know im a little late with my response because guess my mind had responded and not my hands, those modules suggested seem totally reasonable and I will be purchasing them soon!
     
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