433MHz remote measurement modules

Discussion in 'The Projects Forum' started by kender, Aug 23, 2007.

  1. kender

    Thread Starter Senior Member

    Jan 17, 2007
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    My question is not directly related to sensors, it’s more about wireless communication. I’m posting this question here, because you, guys, have seen a lot of instrumentation in your travels.

    I’m looking for a wireless remote measurement system that communicates at 433MHz or lower frequency. FCC compliance is not a problem, because it will be working for one month, and it will be shielded from the outside world by a chainlink fence.

    The purpose of the system is to measure and transmit gas pressure few times a minute for a month. The range is 50 to 100 meters. 4 or 6 units per base station Of course, I can add my own pressure sensor to a system that has an A/D.

    I’m looking for something that’s pretty small – about the size of a 9V battery

    I guess, I could put such system together myself, but I’ve got a very short notice, and I will need to field this system very soon, that’s why I’m looking for OEM modules.

    Could anyone recommend?

    Thanks,
    Nick

    P.S. … back to web search.
     
  2. hgmjr

    Moderator

    Jan 28, 2005
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  3. n9352527

    AAC Fanatic!

    Oct 14, 2005
    1,198
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    Or crossbow http://www.xbow.com/.

    But they have only 2.4GHz, 868MHz and 916MHz systems. Otherwise excellent Zigbee based products, and the motes are pretty small and efficient with battery.
     
  4. mrmeval

    Distinguished Member

    Jun 30, 2006
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  5. kender

    Thread Starter Senior Member

    Jan 17, 2007
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    I’ve seen these. The transmitters are transmit-only. The receiver is too big to install into the remote unit together with the transmitter. In the worst case, I’ll have only one transmitter for real-time monitoring (instead of, say, 6) and the other 5 will have small loggers.

    Way too big.
     
  6. hgmjr

    Moderator

    Jan 28, 2005
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    Do you need the receiver as well as the tranmitter to be the size of a standard 9 volt battery?

    hgmjr
     
  7. kender

    Thread Starter Senior Member

    Jan 17, 2007
    263
    0
    The remote measurement unit should be smaller than 9V battery, including it's own small coin cell battery.
    There are no constraints on the size of the base station. In fact I can have multiple basestations, if each remote-basestation pair can run on its own frequency without interfering with other such pairs.
     
  8. hgmjr

    Moderator

    Jan 28, 2005
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    Have you determined whether the TWS-434 and the RWS-434 transmit/receive modules from www.rentron.com satisfy your design requirements both in size and range?

    hgmjr
     
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