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Re: [wsjtgroup] Re: Experimental Digital Modes

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  • Steinar Aanesland
    Hi Joe, Is there any progress in developing this new modes? Right now there is a 100mW JT2 test transmission on 7.000,860 from UK. I can see it in the
    Message 1 of 8 , Nov 13, 2007
      Hi Joe,

      Is there any progress in developing this new modes?
      Right now there is a 100mW JT2 test transmission on 7.000,860 from UK.
      I can see it in the waterfall, but I am not able to decode the signal .

      73 de LA5VNA Steinar





      Joe Taylor skrev:
      >
      > To: Users of WSJT
      > From: Joe Taylor, K1JT
      > Subject: Experimental Modes JT2 and JT4
      > Date: October 11, 2007
      >
      > Thanks to all who have tested the experimental modes JT2 and
      > JT4 in WSJT 5.9.8 r558 ... and special thanks if you
      > reported your observations to me or on one of the relevant
      > reflectors, or sent me representative wave files. I can
      > report that over the past few days QSOs have now been made
      > with both JT2 and JT4 on amateur bands and propagation modes
      > ranging from trans-Atlantic nighttime DX on 1.8 MHz to 144
      > MHz EME. In addition, JT4 has been used to send and receive
      > messages on 10 GHz EME.
      >
      > If you have not sent comments or a report, it's not too
      > late! Please note that some of the most useful wave files
      > are those containing received signals that you think
      > "should" have decoded, but did not. I am interested in
      > reports of all types of on-the-air tests, from HF to microwaves.
      >
      > As described in the announcement posted several days ago at
      > http://physics.princeton.edu/pulsar/K1JT/JT2_JT4.TXT
      > <http://physics.princeton.edu/pulsar/K1JT/JT2_JT4.TXT> , the
      > new modes are basically functional but do not yet have
      > certain amenities that JT65 users are accustomed to. The
      > new modes show considerable promise, but for a number of
      > reasons they are not yet ready for general use:
      >
      > 1. Decoding performance is overly dependent on the average
      > audio level at the sound card input, and perhaps other factors.
      >
      > 2. Software AFC should be included, to correct small
      > frequency drifts.
      >
      > 3. Options for message averaging and matched filtering
      > should be included in the decoders.
      >
      > These improvements should not be very difficult to make, but
      > my own schedule is such that they will probably take at
      > least some weeks to complete.
      >
      > I have not heard much from others about the appearance of
      > JT2 and JT4 signals on the SpecJT waterfall, or the
      > perceived operational importance of the narrow bandwidths of
      > these modes compared to JT65. Some relevant facts are these:
      >
      > 1. JT65B, the dominant mode for 144 MHz EME, has bandwidth
      > B=355 Hz. JT65A, mostly used on HF and 50 MHz, had B=177
      > Hz. These modes have a narrow "sync tone" only 2.7 Hz wide,
      > which is easy to recognize on a waterfall display.
      >
      > 2. JT2 has bandwidth B=8.75 Hz and JT4A B=17.5 Hz. In these
      > modes sync information is embedded in the data stream.
      > Waterfall traces of JT2 and JT4 signals are therefore much
      > narrower than the full extent of JT65 signals, but appear
      > "fuzzy" compared to the JT65 sync tone.
      >
      > 3. Many JT2 or JT4A signals can fit into the bandpass of a
      > standard SSB transceiver without interfering. This means
      > that random digital EME operation could become easy if, for
      > example, JT2 activity were concentrated in a relatively
      > small (5 or 10 kHz?) portion of each band. It would then be
      > possible for WSJT to acquire many of the advantages of the
      > MAP65 software, which at present are available only to those
      > with wide-band receiving systems like Linrad.
      >
      > 4. The probability for collisions between JT65 signals or
      > between a JT65 signal and a birdie is much larger than that
      > for the much narrower JT2 or JT4A signals. On the other
      > hand, the JT65 decoder is relatively mature and has been
      > made remarkably immune to QRM. The performance of JT2 and
      > JT4 in comparable situations is not yet known.
      >
      > Community input on these matters is needed! Assuming that
      > the present deficiencies of JT2/JT4 can be corrected, so
      > that S/N performance is essentially equal to that of JT65,
      > do you consider the narrow bandwidth of JT2/JT4 to be a
      > significant advantage? Or should we forget about JT2/JT4
      > (at least on bands where JT65 is now widely used), and stick
      > with JT65? Please share your views on these and any other
      > questions you think relevant.
      >
      > -- 73, Joe, K1JT
      >
      > PS: I will be traveling for much of the next week, so any
      > responses will likely be delayed.
      >
      > For reference:
      >
      > The original announcement about JT2 and JT4 is at
      > http://physics.princeton.edu/pulsar/K1JT/JT2_JT4.TXT
      > <http://physics.princeton.edu/pulsar/K1JT/JT2_JT4.TXT> .
      >
      > The experimental version of WSJT with these modes can be
      > downloaded from
      > http://physics.princeton.edu/pulsar/K1JT/WSJT598.EXE
      > <http://physics.princeton.edu/pulsar/K1JT/WSJT598.EXE> .
      >
      >
    • ka2aev@aol.com
      In a message dated 11/13/2007 12:48:21 P.M. Eastern Standard Time, saanes@broadpark.no writes: Hi Joe, Is there any progress in developing this new modes?
      Message 2 of 8 , Nov 13, 2007
        In a message dated 11/13/2007 12:48:21 P.M. Eastern Standard Time,
        saanes@... writes:
        Hi Joe,

        Is there any progress in developing this new modes?
        Right now there is a 100mW JT2 test transmission on 7.000,860 from UK.
        I can see it in the waterfall, but I am not able to decode the signal .

        73 de LA5VNA Steinar



        Steinar can you confirm that frequency of operation please?

        Mike
        KA2AEV




        ************************************** See what's new at http://www.aol.com
      • Steinar Aanesland
        Hi Mike, Yes , after some monitoring I finally picked up this : 175600 5 -20 1.5 0 5 * GKI Z3YC7 1 0 73 de LA5VNA Steinar
        Message 3 of 8 , Nov 13, 2007
          Hi Mike,

          Yes , after some monitoring I finally picked up this :

          175600 5 -20 1.5 0 5 * GKI Z3YC7 1 0

          73 de LA5VNA Steinar





          ka2aev@... skrev:
          >
          > In a message dated 11/13/2007 12:48:21 P.M. Eastern Standard Time,
          > saanes@... <mailto:saanes%40broadpark.no> writes:
          > Hi Joe,
          >
          > Is there any progress in developing this new modes?
          > Right now there is a 100mW JT2 test transmission on 7.000,860 from UK.
          > I can see it in the waterfall, but I am not able to decode the signal .
          >
          > 73 de LA5VNA Steinar
          >
          > Steinar can you confirm that frequency of operation please?
          >
          > Mike
          > KA2AEV
          >
          > ************************************** See what's new at
          > http://www.aol.com <http://www.aol.com>
          >
          >
        • ka2aev@aol.com
          Okay but on what frequency??? Mike KA2AEV In a message dated 11/13/2007 1:59:39 P.M. Eastern Standard Time, saanes@broadpark.no writes: Hi Mike, Yes , after
          Message 4 of 8 , Nov 13, 2007
            Okay but on what frequency???
            Mike
            KA2AEV



            In a message dated 11/13/2007 1:59:39 P.M. Eastern Standard Time,
            saanes@... writes:
            Hi Mike,

            Yes , after some monitoring I finally picked up this :

            175600 5 -20 1.5 0 5 * GKI Z3YC7 1 0

            73 de LA5VNA Steinar

            ka2aev@... skrev:
            >
            > In a message dated 11/13/2007 12:48:21 P.M. Eastern Standard Time,
            > saanes@... <mailto:saanes%40broadpark.no> writes:
            > Hi Joe,
            >
            > Is there any progress in developing this new modes?
            > Right now there is a 100mW JT2 test transmission on 7.000,860 from UK.
            > I can see it in the waterfall, but I am not able to decode the signal .
            >
            > 73 de LA5VNA Steinar
            >
            > Steinar can you confirm that frequency of operation please?
            >
            > Mike
            > KA2AEV
            >




            ************************************** See what's new at http://www.aol.com
          • Steinar Aanesland
            7.000,860 Mhz (dial) +1265Hz S
            Message 5 of 8 , Nov 13, 2007
              7.000,860 Mhz (dial) +1265Hz

              S


              ka2aev@... skrev:
              >
              >
              >
              > Okay but on what frequency???
              > Mike
              > KA2AEV
              >
              > In a message dated 11/13/2007 1:59:39 P.M. Eastern Standard Time,
              > saanes@... <mailto:saanes%40broadpark.no> writes:
              > Hi Mike,
              >
              > Yes , after some monitoring I finally picked up this :
              >
              > 175600 5 -20 1.5 0 5 * GKI Z3YC7 1 0
              >
              > 73 de LA5VNA Steinar
              >
              > ka2aev@... <mailto:ka2aev%40aol.com> skrev:
              > >
              > > In a message dated 11/13/2007 12:48:21 P.M. Eastern Standard Time,
              > > saanes@... <mailto:saanes%40broadpark.no>
              > <mailto:saanes%40broadpark.no> writes:
              > > Hi Joe,
              > >
              > > Is there any progress in developing this new modes?
              > > Right now there is a 100mW JT2 test transmission on 7.000,860 from UK.
              > > I can see it in the waterfall, but I am not able to decode the signal .
              > >
              > > 73 de LA5VNA Steinar
              > >
              > > Steinar can you confirm that frequency of operation please?
              > >
              > > Mike
              > > KA2AEV
              > >
              >
              > ************************************** See what's new at
              > http://www.aol.com <http://www.aol.com>
              >
              >
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