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Re: [wsjtgroup] US Government uses MS propagation for remote sensors

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  • Larry
    Anybody know what frequency this system operates on? I seem to recall something like this operating around 50 MHz but can t remember any details now. It would
    Message 1 of 5 , Jan 4, 2008
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      Anybody know what frequency this system operates on? I seem to recall something like this operating around 50 MHz but can't remember any details now. It would be nice to be able to monitor.

      Larry - W7IUV
      DN07dg
      http://w7iuv.com
    • Steve McDonald
      Larry - they are on 40.529.3. Likely they are really on 40.530 but I listen to them with my rx in the usb mode. You can hear the master stations and the slaves
      Message 2 of 5 , Jan 4, 2008
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        Larry - they are on 40.529.3. Likely they are really on 40.530 but I listen
        to them with my rx in the usb mode. You can hear the master stations and the
        slaves pinging data to each other on meteors nicely here in the PNW.

        Steve / VE7SL



        Web: "THE VE7SL RADIO NOTEBOOK" at http://www.imagenisp.ca/jsm


        > Anybody know what frequency this system operates on? I seem to recall
        something like this operating around 50 MHz but can't remember any details
        now. It would be nice to be able to monitor.
        >
        >
        > Larry - W7IUV
        > DN07dg
        > http://w7iuv.com
      • Larry
        Steve, Listened last night and this morning for a while. Can hear pings every few seconds and sounds almost like FSK441. This might prove to be a good
        Message 3 of 5 , Jan 5, 2008
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          Steve,

          Listened last night and this morning for a while. Can hear pings every
          few seconds and sounds almost like FSK441. This might prove to be a good
          indicator of meteor activity. would be nice to have software that would
          at least decode the station ID/location.

          Larry

          Larry - W7IUV
          DN07dg
          http://w7iuv.com



          Steve McDonald wrote:
          > Larry - they are on 40.529.3. Likely they are really on 40.530 but I listen
          > to them with my rx in the usb mode. You can hear the master stations and the
          > slaves pinging data to each other on meteors nicely here in the PNW.
          >
          > Steve / VE7SL
          >
        • Dave hartzell
          I have a paper somewhere (that I can t find now) describing the SNOTEL network. Its actually quite interesting. From memory (and a little googling), I recall
          Message 4 of 5 , Jan 5, 2008
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            I have a paper somewhere (that I can't find now) describing the SNOTEL
            network. Its actually quite interesting.

            From memory (and a little googling), I recall that the sensing nodes
            use omidirectional antennas and transmit about 100 watts, and the
            master nodes use 1500 watts via directional antennas to enable 2-way
            communications. I wonder what FEC and/or ACKs they need and how many
            repeats! I think they're using FSK as well. SNOTEL uses 40.530 and
            41.530 MHz, but I'm not sure which frequency is paired with the master
            nodes or the remote nodes.

            The paper to which I'm referring is a few years old, but describes
            about 5-6 meteor scatter networks. There might actually be other
            meteor burst networks in operation today. The military was very
            interested in the technology, and a few companies (Radyne?) have (or
            had) commercial products for it.

            There are a few books on meteor burst communications. Here is one
            that I have been trying to get, without the high price, of course!
            ;-)

            http://www.amazon.com/Meteor-Burst-Communications-Theory-Practice/dp/0471522120/ref=sr_1_2?ie=UTF8&s=books&qid=1199554868&sr=8-2

            A few months ago I posted a note to this group asking about setting up
            a beacon network, but there might already be such a thing that would
            be useful to us (SNOTEL)...

            73,
            Dave
            n0tgd

            On Jan 5, 2008 7:47 AM, Larry <larry@...> wrote:
            >

            > Steve,
            >
            > Listened last night and this morning for a while. Can hear pings every
            > few seconds and sounds almost like FSK441. This might prove to be a good
            > indicator of meteor activity. would be nice to have software that would
            > at least decode the station ID/location.
            >
            > Larry
            >
            >
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