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Re: HF APRS and Q15X25 ?

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  • Charles Brabham
    ... There is some APRS activity on the upper end of 30 meters, that I see regularly. I dunno about other HF APRS, but I m sure there s plenty of it out there.
    Message 1 of 17 , Sep 27, 2005
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      --- In Q15X25@yahoogroups.com, kd4e <kd4e@v...> wrote:
      > This leaves open a key question -- is anyone operating
      > HF-APRS? If not, why not?
      >

      There is some APRS activity on the upper end of 30 meters, that I see
      regularly.

      I dunno about other HF APRS, but I'm sure there's plenty of it out
      there.

      APRS is not suited for much more than a few lines of text info. That's
      about it.

      Charles, N5PVL
    • Jose Amador
      ... LINE, ... the ... Of course, I was refering to the non ham stuff. It is faster and easier, but does not carry the same ham radio spirit that I found in
      Message 2 of 17 , Sep 27, 2005
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        --- Charles Brabham <n5pvl@...> wrote:

        >> <co2ja@y...> wrote:
        >>
        >> The fuller picture I see is that "packet radio" has
        >> been associated for a long time with the Bell modem
        >> tones and modulation (which were developed for
        LINE,
        >> not for a RADIO environment), and that development
        >> in that area became stagnant for too long, while
        the
        >> rest of the networking scene did not stop.

        > I'm not sure which 'networking scene' you are
        > talking about there, Jose.
        > The non-ham stuff literally does not apply in a
        > discussion about
        > amateur radio. Some of it is useful, but a great
        > deal of it is not.


        Of course, I was refering to the non ham stuff. It is
        faster and easier, but does not carry the same ham
        radio spirit that I found in packet radio, being a
        user since 1990 an a sysop since 1992.


        > Good, bad, old or new, no amateur radio networking
        > system has been
        > developed that shows any significant improvement
        > over what we already
        > have in the so-called "Packet" network, which
        > utilizes the same
        > partially meshed network topology that the Internet
        > does.


        Well, I have been using pactor for BBS HF forwarding
        since 1998, with the same FBB BBS with a tenfold
        increase in thruput. Obviously the modem and protocol
        are important issues.

        Nevertheless, routing has suffered and now is much
        poorer than what was available in 1995.

        I had about 100 kb of compressed fwd per day with 300
        baud HF packet, and a megabyte or more with pactor.
        More than what anyone may read in a day.


        > There is an advanced networking system under
        > test/development, but
        > nothing that is in general use right now.
        >
        > Understand that I am not saying these things because
        > of any particular
        > preference for what we have now over new stuff. -
        > All I ask is that
        > the 'new stuff' we talk about improving things with
        > - actually exists.
        >
        > Dissing what is currently in use does nothing to
        > improve anything.
        > Developing a poor attitude about the best tools
        > currently at our
        > disposal will not lead to progress, only stagnation.
        > - That is the
        > primary reason why TAPR and the HSMM group never
        > accomplish anything
        > more tangible than whining complaints about what
        > other amateurs do, and
        > the primary reason why the European digital ham
        > radio network is more
        > than a decade ahead of anything in the USA. - ( For
        > the time being, at
        > any rate. )
        >
        > The simple little thing that consistently whizzes
        > over the heads of US
        > digital enthusiasts are concepts of cooperation with
        > and respect for
        > thier fellow hams, most especially those who do
        > something different.
        >
        > It really doesn't matter how clever you are in a
        > technical sense, if
        > you are too stupid and arrogant to play well with
        > others. - And that's
        > the main holdup, here in the US.
        >
        > Charles, N5PVL

        Pactor and multitone modems do far better than 300
        baud FSK for packet. But I had to experience it
        personally to see that the modem stuff is something
        that may be improved.

        I did have scanning working (the CAT on my radio is
        damaged now) and it allowed to dodge bad propagation,
        because the ionosphere does not follows the timings of
        our forwarding scripts....

        I believe that better modems and perhaps ALE would
        hold some promise for improvement...if there were
        enough people to run the HF network as it was 10 years
        ago.

        73 de Jose, CO2JA.
      • Jose Amador
        ... Something I did not mention on my other reply. I had to run 600 watts to achieve some 100 kb of compressed fwd per day. With pactor, 25 to 100 watts
        Message 3 of 17 , Sep 27, 2005
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          --- Tapio Sokura <oh2kku@...> wrote:

          > Charles Brabham wrote:
          > > If you want the very best digital mode possible
          > for APRS, then you are
          > > talking about HF Packet.
          >
          > I'm not convinced. I've spent a considerable amount
          > of time listening on
          > the traffic on 10151 kHz and only a small portion of
          > the packets are
          > decoded. You need a heavy signal, and even then all
          > it takes is a small
          > crack or quick fade in/out and the packet is gone.
          >
          > True, q15x25 was not designed for APRS, but neither
          > was 300 bps packet.
          > The speed of q15x25 is not what I'm looking for, I'm
          > more after
          > reliability of getting the packets through than
          > actual speed or channel
          > capacity. With the FEC and small packets I doubt
          > that q15x25 would in
          > reality be any faster than 300 bps packet, but it
          > could be more reliable.
          >
          > But I'm open to any other layer 1 suggestions as
          > well. Q15X25 came to my
          > mind because it already implements the AX.25 control
          > structures, so it
          > would be plug'n'play to test.
          >
          > Tapio

          Something I did not mention on my other reply. I had
          to run 600 watts to "achieve" some 100 kb of
          compressed fwd per day.

          With pactor, 25 to 100 watts were able to move ten
          times more traffic. I had a link with Africa for
          forwarding to Europe which worked many times with as
          little as 25 watts with better thruput than 300 baud
          packet with 600 watts in much shorter links.

          Jose, CO2JA
        • kd4e
          ... Which version of Pactor, please? Pactor III is proprietary and expensive and thus not an available tool for most Hams. The proprietary nature of Pactor III
          Message 4 of 17 , Sep 29, 2005
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            > Something I did not mention on my other reply. I had
            > to run 600 watts to "achieve" some 100 kb of
            > compressed fwd per day.
            >
            > With pactor, 25 to 100 watts were able to move ten
            > times more traffic. I had a link with Africa for
            > forwarding to Europe which worked many times with as
            > little as 25 watts with better thruput than 300 baud
            > packet with 600 watts in much shorter links.
            >
            > Jose, CO2JA

            Which version of Pactor, please?

            Pactor III is proprietary and expensive and thus not an
            available tool for most Hams.

            The proprietary nature of Pactor III makes self-regulation,
            a FCC priority, impossible given the inability for the
            average Ham to even monitor the traffic.

            It may be superior in certain ways and not in others
            but since it is not affordable nor healthy for Ham
            radio it is not the answer to the need.
          • Charles Brabham
            ... Personally, I have never heard of a Packet BBS SYSOP before who ran more than 50-70 watts power. If you were running 600 watts, that may have been part of
            Message 5 of 17 , Sep 30, 2005
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              --- In Q15X25@yahoogroups.com, Jose Amador <co2ja@y...> wrote:
              >
              > Something I did not mention on my other reply. I had
              > to run 600 watts to "achieve" some 100 kb of
              > compressed fwd per day.
              >
              > With pactor, 25 to 100 watts were able to move ten
              > times more traffic. I had a link with Africa for
              > forwarding to Europe which worked many times with as
              > little as 25 watts with better thruput than 300 baud
              > packet with 600 watts in much shorter links.
              >
              > Jose, CO2JA

              Personally, I have never heard of a Packet BBS SYSOP before who ran
              more than 50-70 watts power. If you were running 600 watts, that may
              have been part of your problem with Packet.

              Were the stations you connected to all running 600 watts too? - Or
              were they running 50-70 watts, as all the SYSOPs I know have found to
              be work out best? ( I know a lot of SYSOPs, by the way. )

              Your story doesn't make a lot of sense... I have operated both modes
              and though PACTOR does give better throughput, it does not do so for
              all of the BBS software currently in use.

              PACTOR is also prohibitively expensive, and has virtually no signal
              detection capability, very often making PACTOR operators into
              unwilling ( and unwitting ) lids. Lots of BBS SYSOPs won't go for
              being party to that.

              Add the greatly expanded bandwidth of the higher performing PACTOR
              modes, and you have a nice QRM generation system there, second to
              none when it comes to crashing people's QSO's.

              Then there is the difficulty in trying to operate multiple PACTOR
              QSO's on a single frequency. Packet handles this just fine, PACTOR
              does not.

              Most SYSOPs utilize Packet because nothing better has come along to
              replace it. - You are welcome to consider PACTOR as a 'better'
              replacemnent for Packet if you wish, but understand that by doing so,
              you place yourself with a tiny minority among BBS SYSOPs, for the
              reasons outlined above.

              That's just how it is, agree with it or not as you wish. Whatever
              PACTOR is, it is not a "replacement" for Packet. - Good or bad.

              Charles, N5PVL
            • Jose Amador
              ... than 300 baud packet with 600 watts in much shorter ... Pactor II. ... Seems to be a matter of luck, as many other things in the human existence. And
              Message 6 of 17 , Sep 30, 2005
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                --- kd4e <kd4e@...> wrote:

                > > Something I did not mention on my other reply. I
                > > had to run 600 watts to "achieve" some 100 kb of
                > > compressed fwd per day.
                > >
                > > With pactor, 25 to 100 watts were able to move
                > > ten times more traffic. I had a link with Africa
                > > for forwarding to Europe which worked many times
                > > with as little as 25 watts with better thruput
                than > > 300 baud packet with 600 watts in much
                shorter
                > > links.

                > Which version of Pactor, please?

                Pactor II.

                > Pactor III is proprietary and expensive and thus not
                > an available tool for most Hams.

                > It may be superior in certain ways and not in others
                > but since it is not affordable nor healthy for Ham
                > radio it is not the answer to the need.

                Seems to be a matter of luck, as many other things in
                the human existence.

                And of course, the need arises from the fact that
                something much better than packet exists and is not
                widely available.

                Plain pactor with memory ARQ achieves a thereshold 10
                dB lower than RTTY, and P II 18 dB lower. That may
                explain the lower power required to establish a link.

                Since it is a one to one link, there are no
                collissions, perhaps, maybe, ocassional QRM from
                others who consider to own certain frequencies. The
                transfer protocol is more elaborate and better
                (compression, interleaving, convolutional encoding,
                Viterbi decoding, etc).

                No wonder that some techniques used for space
                communications can also help in terrestrial comms.

                I have been following Q15X25 as it may have better
                characteristics, those of modern HF data
                communications systems.

                Certainly, 300 baud FSK is far from optimal.

                Q15X25 and similar modulation methods may allow to
                have more people to communicate with on HF. With
                recent developments, there seems to be hope for may of
                us.

                73 de Jose, CO2JA
              • kd4e
                ... If I recall Pactor II may be monitored without the costly proprietary SCS hardware and software, so it may be a more acceptable app in Ham use -- at least
                Message 7 of 17 , Oct 1, 2005
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                  > Since it is a one to one link, there are no
                  > collissions, perhaps, maybe, ocassional QRM from
                  > others who consider to own certain frequencies. The
                  > transfer protocol is more elaborate and better
                  > (compression, interleaving, convolutional encoding,
                  > Viterbi decoding, etc).

                  If I recall Pactor II may be monitored without the
                  costly proprietary SCS hardware and software, so it
                  may be a more acceptable app in Ham use -- at least
                  one may determine who the QRMing offender is and
                  report them -- one may also determine is the op is
                  sending Ham-legal communications or something else.

                  QRMing is rarely against folks camoing out on a
                  freq 24/7 but most often the result of someone
                  engaged in a QSO where another op is too careless
                  or selfish to bother to check for activity and
                  who jumps on top of them.

                  There is no lack of space on the bands, except perhaps
                  during the all-too-frequent contests, so there is no
                  excuse for QRMing -- especially witha digital signal
                  that cannot be decoded by 99% of Hams and may be
                  readily abused for non-Ham legal or nefarious purposes

                  > I have been following Q15X25 as it may have better
                  > characteristics, those of modern HF data
                  > communications systems.

                  That is why we are all on this list.

                  > Certainly, 300 baud FSK is far from optimal.

                  For sure -- but that may also be a regulatory quirk
                  choking-off new technologies that needs to be addressed.

                  > Q15X25 and similar modulation methods may allow to
                  > have more people to communicate with on HF. With
                  > recent developments, there seems to be hope for may of
                  > us.

                  Agreed.

                  > 73 de Jose, CO2JA
                • Jose Amador
                  ... It might fit in your frame if we used, as you do, a BBS only frequency. We did not, anyone could connect freely. Perhaps that´s part of my problem with
                  Message 8 of 17 , Oct 1, 2005
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                    --- Charles Brabham <n5pvl@...> wrote:

                    > --- In Q15X25@yahoogroups.com, Jose Amador
                    > <co2ja@y...> wrote:
                    > >
                    > > Something I did not mention on my other reply. I
                    > had
                    > > to run 600 watts to "achieve" some 100 kb of
                    > > compressed fwd per day.
                    > >
                    > > With pactor, 25 to 100 watts were able to move
                    > ten
                    > > times more traffic. I had a link with Africa for
                    > > forwarding to Europe which worked many times with
                    > as
                    > > little as 25 watts with better thruput than 300
                    > baud
                    > > packet with 600 watts in much shorter links.
                    > >
                    > > Jose, CO2JA
                    >
                    > Personally, I have never heard of a Packet BBS SYSOP
                    > before who ran
                    > more than 50-70 watts power. If you were running 600
                    > watts, that may
                    > have been part of your problem with Packet.

                    > Were the stations you connected to all running 600
                    > watts too? - Or
                    > were they running 50-70 watts, as all the SYSOPs I
                    > know have found to
                    > be work out best? ( I know a lot of SYSOPs, by the
                    > way. )

                    It might fit in your frame if we used, as you do, a
                    BBS only frequency. We did not, anyone could connect
                    freely.

                    Perhaps that´s part of my problem with packet, I hate
                    losing time with bad links and retries. I was able to
                    do it, those were my finals and my power bill, at the
                    service of my users. And it never caused problems to
                    anyone. I do not operate a HF packet forwarding link
                    since 1998. With pactor, or whatever replaces 300 baud
                    FSK modems, it is not necessary to run high power to
                    run a reliable link.

                    > Your story doesn't make a lot of sense... I have
                    > operated both modes
                    > and though PACTOR does give better throughput, it
                    > does not do so for
                    > all of the BBS software currently in use.

                    So, what makes sense is to use the BEST BBS software.

                    I understand it does not make sense to you, but not
                    all BBS programmers (and I do not mean to offend any
                    of them) are equally gifted. Only the best software
                    did survive.

                    > PACTOR is also prohibitively expensive, and has
                    > virtually no signal
                    > detection capability, very often making PACTOR
                    > operators into
                    > unwilling ( and unwitting ) lids. Lots of BBS SYSOPs
                    > won't go for
                    > being party to that.

                    I do not want to impose that on anyone. Have I meant
                    that? Never.

                    > Add the greatly expanded bandwidth of the higher
                    > performing PACTOR
                    > modes, and you have a nice QRM generation system
                    > there, second to
                    > none when it comes to crashing people's QSO's.

                    Pactor 2 fits into my CW filter.

                    > Then there is the difficulty in trying to operate
                    > multiple PACTOR
                    > QSO's on a single frequency. Packet handles this
                    > just fine, PACTOR
                    > does not.

                    Pactor is not meant to do that. If you operated it,
                    and read the manual, you know that it does not make
                    sense to make that comparison.

                    > Most SYSOPs utilize Packet because nothing better
                    > has come along to
                    > replace it. - You are welcome to consider PACTOR as
                    > a 'better'
                    > replacemnent for Packet if you wish, but understand
                    > that by doing so,
                    > you place yourself with a tiny minority among BBS
                    > SYSOPs, for the
                    > reasons outlined above.

                    I do not do Internet forwarding. And you might know
                    that time in HF forwarding counts, when the bands are
                    not open 24/24 like a wire or VHF/UHF.

                    > That's just how it is, agree with it or not as you
                    > wish. Whatever
                    > PACTOR is, it is not a "replacement" for Packet. -
                    > Good or bad.
                    >
                    > Charles, N5PVL

                    I respect your point of view, you are entitled to it.

                    But I also feel I have the right to disagree. As I
                    disagree to go into a name calling fight that solves
                    nothing.

                    And period. End of the thread, at least for me, it is
                    not relevant to Q15X25.

                    Jose
                  • Mark Miller
                    ... Do you recall how this is done? I have only seen monitoring software for PACTOR I and am interested in monitoring PACTOR II. 73, Mark N5RFX
                    Message 9 of 17 , Oct 4, 2005
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                      At 07:43 AM 10/1/2005, you wrote:
                      >If I recall Pactor II may be monitored without the
                      >costly proprietary SCS hardware and software, so it
                      >may be a more acceptable app in Ham use --

                      Do you recall how this is done? I have only seen monitoring software for
                      PACTOR I and am interested in monitoring PACTOR II.

                      73,

                      Mark N5RFX
                    • wb8wka
                      APRS is not tied to AX.25. Most of the display programs as well as internet servers let you input data in a text format. The APRS spec is here:
                      Message 10 of 17 , Oct 7, 2005
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                        APRS is not tied to AX.25. Most of the display programs as well as
                        internet servers let you input data in a text format. The APRS spec is
                        here: http://www.tapr.org/aprs_working_group.html

                        Being most APRS position reports are from 13 to 40 bytes long (native
                        APRS format) you don't need the speed of Q15X25. Also, most APRS
                        transmissions in the wild are UI frames, or unacknowledged information
                        frames. Meaning, they don't use the connected mode (or ARQ) function
                        of ax.25.

                        If your looking to optimize HF APRS from the present AX.25 UI frame
                        300 baud means, you'd be better off looking at a mode that offers
                        heavy FEC and good low signal performance. MT63, MFSK16 or perhaps
                        Olivia come to mind. All offer good low signal performance and heavy
                        FEC.

                        300 baud on HF, as a signaling rate, is less then optimal due to group
                        delay caused by different paths through the ionosphere. That is the
                        reason Q15X25 reduced the baud rate to 83.5 (on each carrier) to
                        reduce this effect.

                        Good luck.



                        --- In Q15X25@yahoogroups.com, Tapio Sokura <oh2kku@i...> wrote:
                        >
                        > Hi,
                        >
                        > I was wondering if there are any established a) frequencies and/or
                        b)
                        > Q15X25 modem parameters for HF APRS use? 300 bps packet seems to be
                        a
                        > lot less than optimal on HF and it would be interesting to see how
                        > Q15X25 would do instead. I did some googling on this subject, but
                        didn't
                        > find any concrete information on frequencies/parameters, just some
                        pages
                        > that mention the possibility of combining the two.
                        >
                        > Tapio
                        >
                      • Charles Brabham
                        ... If you are not operating within the automated sub-bands, then you are most definately QRM ing other hams with your PACTOR signals. The one and only place
                        Message 11 of 17 , Oct 8, 2005
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                          > > Were the stations you connected to all running 600
                          > > watts too? - Or
                          > > were they running 50-70 watts, as all the SYSOPs I
                          > > know have found to
                          > > be work out best? ( I know a lot of SYSOPs, by the
                          > > way. )
                          >
                          > It might fit in your frame if we used, as you do, a
                          > BBS only frequency. We did not, anyone could connect
                          > freely.

                          If you are not operating within the automated sub-bands, then you are
                          most definately QRM'ing other hams with your PACTOR signals.

                          The one and only place where you can operate PACTOR ( or Packet ) for
                          BBS operation without regularly crashing people's QSO's are the
                          automated sub-bands.

                          That's why they exist.

                          Packet BBS operation as a 'loner' who does not play by the rules
                          other SYSOPs operate by is a pointless endeavor. Competent
                          autoforwarding's first requirement is an ability to play well with
                          others, in a cooperative way and friendly way.

                          > With pactor, or whatever replaces 300 baud
                          > FSK modems, it is not necessary to run high power to
                          > run a reliable link.

                          You are the one and only amateur who has ever suggested to me that
                          Packet is unreliable except when using high power.

                          From my location at the southern tip of Texas, I forward regularly
                          with stations in Canada, California, Indiana, Florida and ( Here's an
                          easy one ) Missouri. - All with 50 watts on HF Packet.

                          > > Your story doesn't make a lot of sense... I have
                          > > operated both modes
                          > > and though PACTOR does give better throughput, it
                          > > does not do so for
                          > > all of the BBS software currently in use.
                          >
                          > So, what makes sense is to use the BEST BBS software.

                          http://www.uspacket.org/l_protowars.htm

                          What makes sense is to work with protocols/modes that are usable by
                          all BBS software, including the new BBS software that is coming up.

                          > > Then there is the difficulty in trying to operate
                          > > multiple PACTOR
                          > > QSO's on a single frequency. Packet handles this
                          > > just fine, PACTOR
                          > > does not.
                          >
                          > Pactor is not meant to do that. If you operated it,
                          > and read the manual, you know that it does not make
                          > sense to make that comparison.

                          Looks like you are picking and choosing what is or is not 'relevant'
                          according to how well it matches up with your personal views.

                          As manager of an ARRL Skipnet, I can assure you that the ability to
                          operate half a dozen or more stations on one frequency is highly
                          relevant, unless and until somebody comes along and finds a way to
                          greatly expand the autoforwarding sub-bands.

                          If we can only have two stations per frequency, and those stations
                          must be five or six times wider, that means that the network can only
                          have a few participating stations, and so it would have very little
                          coverage or capability, worldwide.

                          We are trying to get more BBS stations to participate, not to shut
                          them out by using inappropriate modes/protocols that do not 'play
                          well with others' and so reduce our capability in this area.

                          It should never be forgotten that participation in a network is a
                          cooperative venture. Your value to that network in large part hinges
                          upon your ability to work cooperatively with many other hams around
                          the world.

                          >
                          > I respect your point of view, you are entitled to it.
                          >
                          > But I also feel I have the right to disagree. As I
                          > disagree to go into a name calling fight that solves
                          > nothing.
                          >
                          > And period. End of the thread, at least for me, it is
                          > not relevant to Q15X25.
                          >

                          Right now I am manager of the NET117 ARRL SkipNet, experimenting with
                          utilizing Q15x25 mode for autoforwarding. In my case at any rate,
                          these questions and discussions are highly relevant to what I do.

                          I have to think about stuff like bandwidth, signal strength, the
                          ability to share a frequency, bitrate, compatability with all ( not
                          just my personal favorite ) BBS software and ease of operation, along
                          with a number of other factors.

                          Personally I would like to see Q15x25 mode go into regular use for
                          autoforwarding - but it is not my job to promote Q15x25. What I am
                          doing is evaluating the mode instead, doing my best to give it a fair
                          chance to show it's stuff. - Both good and bad.

                          I'm beginning to wonder if 17 meters is the best place to do this
                          evaluation, but that's the spot the ARRL folks gave me so that's what
                          I have to work with right now. - I sure wish 15 meters was open more
                          often!

                          Charles, N5PVL
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