Re: [digitalradio] Re: Another look at ALE
While fairly technical at times, the one thing that stood out is that the computational power and especially memory available (3G cell stuff and maybe 256K) is not that large. So it could be implemented. However, this appears more for multicasting in the case of the fountain codes. He indicated that the coding community is moving toward replacing turbo codes with irregular LDPC but I do not understand how this stuff works. If I understand it correctly, it is the raptor codes that have the FEC structure. It is amazing that we can access this kind of multimedia presentation on a time shifted basis and at no charge! 73, Rick, KV9U Leigh L Klotz, Jr. wrote: You might like this talk, which is available in audio and video formats: http://www.parc.com/cms/get_article.php?id=344 It covers Turbo, Tornado, and LDPC codes. The focus is on a FEC mechanism for broadcast to receivers over a noisy channel. LDPC codes are supposedly close to the Shannon limit, though computationally expensive. This talk brings up a lot of these interesting issues. You can hear me ask the speaker if it's OK to use their patented technology for amateur radio and his response, which I interpreted to be ok. Leigh / WA5ZNU Using Powerful FEC Codes for File and Streaming Delivery to Mobile Receivers Michael Luby, Digital Fountain, Inc We describe Raptor codes, the most flexible and powerful FEC codes available for delivery of data over packet-based networks. We demonstrate that Raptor codes are crucial for both efficient delivery of files and for high-quality video streaming over emerging broadcast and multicast wireless networks. Example applications include delivery of navigational updates and point-of-interest data to automobiles and delivery of multimedia files and H.263 streaming video to 3G telephones and PDAs. Standardization of the general approach of using FEC codes for file and streaming delivery within the IETF and 3GPP will also be outlined. Dr. Michael Luby cofounded Digital Fountain, Inc. in 1998, where he currently holds the position of Chief Technology Officer. Michael is a world-renowned Theoretical Computer Scientist, and has made breakthrough research contributions in the areas of coding theory, randomized algorithm design and analysis, transport protocols and cryptography. He is actively leading the development of several transport standards within the Internet Engineering Task Force (IETF). After receiving his Ph.D. in Theoretical Computer Science from UC Berkeley in 1983 he was a Professor in Computer Science at the University of Toronto. In 1988 Michael joined the International Computer Science Institute in Berkeley to become the Leader of the Theory Group and concurrently an Adjunct Professor at UC Berkeley. Michael is a recipient of the 2002 Information Theory Society Paper Award for some of his coding theory research and the 2003 SIAM Outstanding Paper Prize for some of his cryptography research. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: Another look at ALE
I used to think that Viterbi coding worked better for ham applications. For example, Pactor modes (Viterbi) work better than Clover modes (R-S). Other R-S modes include, SSTV RDFT and the Winlink 2000 initial attempt to develop a sound card mode (SCAMP) which uses the same modulation scheme as RDFT. Actually, many of the sound card modes use Viterbi: QPSK31, PSK63F, PSK220F, MFSK16, MFSK8, and even the new DominoEX/FEC mode all use Viterbi coding. Many of the Pactor tricks have been applied to sound card modes, including Huffman compression which is really varicode from what I understand. The use of DPSK is common for sound card modes since PSK31 is really DPSK, is it not? In fact, the waveform is quite similar to Pactor using a raised cosine form. But it still does not explain why Pactor 2 and 3 is so much faster than the sound card modes. Even though many have determined that P2 and P3 can not work as deep into the noise as some sound card modes, other tests seem to refute this. Rick, KN6KB has indicated that the SCS product is tremendously more powerful than any desktop computer at this time since it is a dedicated unit. One other way to increase the coding is to use concatenated codes that include both R-S and Viterbi since we can do this with faster processors. The technology trends seem to replace the concatenated codes with Turbo code that is a more recent development. Is anyone planning to use this for sound card applications? I wonder what would happen if a developer speeded up some of the very weak signal approaches such as WOLF: http://www.scgroup.com/ham/wolf.html 73, Rick, KV9U Jose Amador wrote: Well, about what´s being done the wrong way, I think I better pass it to the codesmiths. I am not completely clear about how the soundcard modes do it, but the success if Pactor is wrapping all those tricks together. Some of the modes use Reed Solomon codes, others use BCH, but I am not sure if any of them uses convolutional encoding with Viterbi decoding. One important point. If my memory does not betray me, I think Pactor uses DPSK, which does better passing by the ionosphere. Seems to be easier to take account of the phase jumps than of the absolute phase. I used at times packet at 1200 baud on 28, 21 and 14 MHz, and it worked in order of decreasing success on the lower frequenciesbut it managed to work on 14MHz quite well at times. Multipath is the deciding factor in the link. If just one path is open, it may work, if there is multipath, better hold back to lower speeds. What surprises me (and I have never been able to test it personally) is that in Indonesia, some hams have used 1200 baud DPSK satellite modes succesfully on 40 meters. Once again, DPSK does the trick. It would be interesting to read about what and why the programmers have chosen their options while creating new sound card modes. 73 de Jose, CO2JA Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: Another look at ALE
--- KV9U [EMAIL PROTECTED] wrote: I still have not understood what P2 and P3 have that is all that special and allows them to run as fast as they do (not to mention they are also ARQ modes). If we had non ARQ modes with similar modulation, why would not that run at a similar rate of transmission even if you did not adjust for adaptive speeds. 73, Rick, KV9U Block coding, to recover errors without retransmission, interleaving, to convert block losses into single bit losses (and make error recovery possible), FEC, in the form of convolutional encoding with Viterbi (soft) with maximum likelyhood decoding. Compression, whenever applicable, reduces the data volume to be sent, and so, content to be mistaken... Of course, multicarrier modulation, to allow high data speeds with low signalling rates, to fight multipath... of course, it requires BANDWIDTH... It is not a single trick, but a boxful of them... 73 de Jose, CO2JA __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Re: Another look at ALE
Title: RE: [digitalradio] Re: Another look at ALE Yes 200 WPM will do but 300-400 WPM or faster would be much better if the same SNR was maintained. However, if going to 300-400 WPM increases the SNR by 5 to 7 dB, then that would be acceptable. For the time being, MT63 seems to be the mode that we will have to use for file transfers and perhaps MFSK16 for keyboard-to-keyboard communications. With gMFSK, its no problem to switch from MT63 to MFSK16. Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:digitalradio@yahoogroups.com]On Behalf Of KV9U Sent: Wednesday, March 15, 2006 9:26 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: Another look at ALE Walt, Initially you had indicated that: I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robus enough to work right down in the noise. That is exactly what MT-63 does. However, now you are indicating you want at least 300-400 and preferably 400-600 wpm which is a whole different category of speed. Is that possible with any common ham mode other than possibly Pactor 2 and 3 which track together into the noise at around 1000 wpm at -10 db according to the ECJones site? I still have not understood what P2 and P3 have that is all that special and allows them to run as fast as they do (not to mention they are also ARQ modes). If we had non ARQ modes with similar modulation, why would not that run at a similar rate of transmission even if you did not adjust for adaptive speeds. 73, Rick, KV9U DuBose Walt Civ AETC CONS/LGCA wrote: Understand that I have used MIL-STD-188-110a and FS-1052(?) modems (modes) when I was in the AF Reserve. I used MIL-STD-188-110a and c (I think) in February of 1990 in US Air Force test, then in California during joint services test in the summer of 1990 and while in Saudi in the fall of 1990. I don't think they are as robust as some of the amateur radio digital modes. Yes, we've used MT63 VERY successfully and it meets 90% of our needs...the 2K Long Interleave is VERY robust...about as robust as we need. If we want a faster turn-around, we will go to short interleave and/or 1K short interleave. The only problem is that the throughput is lower than we need. MT63 2K Long Interleave seems to have a SNR of less than 0 dB on a CCIR Channel (probably between -5 and -7 DB SNR) and the throughput is 200 WPM...we would like to see 400-600 WPM or at least 300-400 WPM. We aren't concerned about band width. Even if the ARRL proposes 3.5 KHz max band width, I think that another proposal going to 6 or 8 KHz for OFDM type modes would be acceptable to the FCC as this is good physics/good electronic engineering and in keeping with good amateur radio practices. Personal Opinion If the FCC says NO to a wider bandwidth, then the choice may be to go to Congress pointing out how the FCC is prohibiting technical research/ experimenting and advancements in communications technology as Part 97 says amateur radio operators should and ask Congress to review the matter. The only reason I say this is that I have talked to three Republican Congressmen and two Democratic Congressmen and they agree that if nothing else besides providing support/auxiliary communications during an Incident or disaster, hams should be experimenting and should have the opportunity to experiment within the ham bands to the maximum extent possible in developing communications techniques...even if they are not directly applicable to commercial or government communications. /Personal Opinion 73, Walt/K5YFW DuBose Walt Civ AETC CONS/LGCA wrote: I might mention that our net operations and net control stations operate much like a state or local EOC (I worked many years in a large city EOC). When I think of what I would like in a mode to support the type of communications I was involved in (and I think most of the disaster relief agencies such as the Red Cross, Salvation Army and the like), I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robust enough to work right down in the noise. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http
Re: [digitalradio] Re: Another look at ALE
I agree completely, Jose. However, all these things can (and often are done) with other modes that do not run as fast. The bandwidths are no differerent than the wider sound card modes at either 500 Hz for Pactor 2 or closer to a voice bandwidth such as Pactor 3 uses. And the Pactor modes don't use particulary unusual modulation schemes either and 100 or 200 baud rates, which while a bit fast for certain kinds of conditions, seems to work better than one would expect. So what are we doing wrong with existing sound card modes? 73, Rick, KV9U Jose Amador wrote: Block coding, to recover errors without retransmission, interleaving, to convert block losses into single bit losses (and make error recovery possible), FEC, in the form of convolutional encoding with Viterbi (soft) with maximum likelyhood decoding. Compression, whenever applicable, reduces the data volume to be sent, and so, content to be mistaken... Of course, multicarrier modulation, to allow high data speeds with low signalling rates, to fight multipath... of course, it requires BANDWIDTH... It is not a single trick, but a boxful of them... 73 de Jose, CO2JA Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: Another look at ALE
--- KV9U [EMAIL PROTECTED] wrote: I agree completely, Jose. However, all these things can (and often are done) with other modes that do not run as fast. The bandwidths are no differerent than the wider sound card modes at either 500 Hz for Pactor 2 or closer to a voice bandwidth such as Pactor 3 uses. And the Pactor modes don't use particulary unusual modulation schemes either and 100 or 200 baud rates, which while a bit fast for certain kinds of conditions, seems to work better than one would expect. So what are we doing wrong with existing sound card modes? 73, Rick, KV9U Well, about what´s being done the wrong way, I think I better pass it to the codesmiths. I am not completely clear about how the soundcard modes do it, but the success if Pactor is wrapping all those tricks together. Some of the modes use Reed Solomon codes, others use BCH, but I am not sure if any of them uses convolutional encoding with Viterbi decoding. One important point. If my memory does not betray me, I think Pactor uses DPSK, which does better passing by the ionosphere. Seems to be easier to take account of the phase jumps than of the absolute phase. I used at times packet at 1200 baud on 28, 21 and 14 MHz, and it worked in order of decreasing success on the lower frequenciesbut it managed to work on 14MHz quite well at times. Multipath is the deciding factor in the link. If just one path is open, it may work, if there is multipath, better hold back to lower speeds. What surprises me (and I have never been able to test it personally) is that in Indonesia, some hams have used 1200 baud DPSK satellite modes succesfully on 40 meters. Once again, DPSK does the trick. It would be interesting to read about what and why the programmers have chosen their options while creating new sound card modes. 73 de Jose, CO2JA __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Re: Another look at ALE
Title: RE: [digitalradio] Re: Another look at ALE Understand that I have used MIL-STD-188-110a and FS-1052(?) modems (modes) when I was in the AF Reserve. I used MIL-STD-188-110a and c (I think) in February of 1990 in US Air Force test, then in California during joint services test in the summer of 1990 and while in Saudi in the fall of 1990. I don't think they are as robust as some of the amateur radio digital modes. Yes, we've used MT63 VERY successfully and it meets 90% of our needs...the 2K Long Interleave is VERY robust...about as robust as we need. If we want a faster turn-around, we will go to short interleave and/or 1K short interleave. The only problem is that the throughput is lower than we need. MT63 2K Long Interleave seems to have a SNR of less than 0 dB on a CCIR Channel (probably between -5 and -7 DB SNR) and the throughput is 200 WPM...we would like to see 400-600 WPM or at least 300-400 WPM. We aren't concerned about band width. Even if the ARRL proposes 3.5 KHz max band width, I think that another proposal going to 6 or 8 KHz for OFDM type modes would be acceptable to the FCC as this is good physics/good electronic engineering and in keeping with good amateur radio practices. Personal Opinion If the FCC says NO to a wider bandwidth, then the choice may be to go to Congress pointing out how the FCC is prohibiting technical research/ experimenting and advancements in communications technology as Part 97 says amateur radio operators should and ask Congress to review the matter. The only reason I say this is that I have talked to three Republican Congressmen and two Democratic Congressmen and they agree that if nothing else besides providing support/auxiliary communications during an Incident or disaster, hams should be experimenting and should have the opportunity to experiment within the ham bands to the maximum extent possible in developing communications techniques...even if they are not directly applicable to commercial or government communications. /Personal Opinion 73, Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:digitalradio@yahoogroups.com]On Behalf Of KV9U Sent: Tuesday, March 14, 2006 10:55 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: Another look at ALE Walt, What you are describing sounds very close to MT-63. 73, Rick, KV9U DuBose Walt Civ AETC CONS/LGCA wrote: There has been some discussion about what mode does what and what is needed/desired. We have had a little discussion on what the problems were during Katrina with digital communications. During hurricanes Katrina and Rita, I worked with a disaster relief group and operated as their HF net control station and a participating station. Our network in Katrina ran from the Mississippi Gulf Coast up to Atlanta back to Louisiana including New Orleans, Batron Rouge, Hammons, Bogalusa and north, Alexandria, Lafayette, Beaumont Texas, Dallas and San Antonio Texas. Most of the time we would have liked to use a keyboard-to-keyboard mode...probably 60% of the time. 20% to 30% of the time Sideband Voice was Ok. But there was 10% of the time when we would have liked to be able to send a rather large data file from our Dallas, San Antonio or Atlanta stations to all of our stations. In many instances conditions were so poor that voice communications didn't work very well at all. Most of the time when sending smaller data packages, reading them by voice worked Ok; however, we have many request for repeats and we had to relay many times. We only operated on three frequencies and primarily on 40 and 75 meters since propagation programs showed that these were the best frequencies to use at the time. I might mention that our net operations and net control stations operate much like a state or local EOC (I worked many years in a large city EOC). When I think of what I would like in a mode to support the type of communications I was involved in (and I think most of the disaster relief agencies such as the Red Cross, Salvation Army and the like), I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robust enough to work right down in the noise. As far as frequency selection, when you only have 2 bands that will support propagation and use only one frequency on each band, channel selection is not a problem. An automatic call ability, such as SELCALL, would be very nice to have. Most of the other capabilities I hear about are nice but not really needed. I believe that the type of operations I was involved in, and will be again this hurricane season, are useful in passing many if not most types of traffic on HF. Thanks and 73, Walt/K5YFW Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group
Re: [digitalradio] Re: Another look at ALE
Walt, Initially you had indicated that: I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robus enough to work right down in the noise. That is exactly what MT-63 does. However, now you are indicating you want at least 300-400 and preferably 400-600 wpm which is a whole different category of speed. Is that possible with any common ham mode other than possibly Pactor 2 and 3 which track together into the noise at around 1000 wpm at -10 db according to the ECJones site? I still have not understood what P2 and P3 have that is all that special and allows them to run as fast as they do (not to mention they are also ARQ modes). If we had non ARQ modes with similar modulation, why would not that run at a similar rate of transmission even if you did not adjust for adaptive speeds. 73, Rick, KV9U DuBose Walt Civ AETC CONS/LGCA wrote: Understand that I have used MIL-STD-188-110a and FS-1052(?) modems (modes) when I was in the AF Reserve. I used MIL-STD-188-110a and c (I think) in February of 1990 in US Air Force test, then in California during joint services test in the summer of 1990 and while in Saudi in the fall of 1990. I don't think they are as robust as some of the amateur radio digital modes. Yes, we've used MT63 VERY successfully and it meets 90% of our needs...the 2K Long Interleave is VERY robust...about as robust as we need. If we want a faster turn-around, we will go to short interleave and/or 1K short interleave. The only problem is that the throughput is lower than we need. MT63 2K Long Interleave seems to have a SNR of less than 0 dB on a CCIR Channel (probably between -5 and -7 DB SNR) and the throughput is 200 WPM...we would like to see 400-600 WPM or at least 300-400 WPM. We aren't concerned about band width. Even if the ARRL proposes 3.5 KHz max band width, I think that another proposal going to 6 or 8 KHz for OFDM type modes would be acceptable to the FCC as this is good physics/good electronic engineering and in keeping with good amateur radio practices. Personal Opinion If the FCC says NO to a wider bandwidth, then the choice may be to go to Congress pointing out how the FCC is prohibiting technical research/ experimenting and advancements in communications technology as Part 97 says amateur radio operators should and ask Congress to review the matter. The only reason I say this is that I have talked to three Republican Congressmen and two Democratic Congressmen and they agree that if nothing else besides providing support/auxiliary communications during an Incident or disaster, hams should be experimenting and should have the opportunity to experiment within the ham bands to the maximum extent possible in developing communications techniques...even if they are not directly applicable to commercial or government communications. /Personal Opinion 73, Walt/K5YFW DuBose Walt Civ AETC CONS/LGCA wrote: I might mention that our net operations and net control stations operate much like a state or local EOC (I worked many years in a large city EOC). When I think of what I would like in a mode to support the type of communications I was involved in (and I think most of the disaster relief agencies such as the Red Cross, Salvation Army and the like), I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robust enough to work right down in the noise. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] Re: Another look at ALE
--- In digitalradio@yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Andy, Are you talking about Automatic Link Establsihment capability to connect to stations or the service messaging protocol of ALE just to send text with? Good question. I started my thoughts in reaction to all the interest here in PAX2, and previously in Olivia. It seems to me that many on this list enjoy the experiments in finding a digital mode that performs well in marginal situations. There are also those that like the ability to beacon and use the radio for digital message handling. ALE , or at least the use of ALE in PC-ALE, appears to provide most of this. I no ALE expert, and only use it on a basic amateur transceiver, but ALE linking , use of trace/soundings, and use of propagation data , appears to help the ham in working under marginal conditions . The digital message ability of PC-ALE appears to provide some of the functions that PAX2 does. I have not really tested how ALE messages work under poor conditions. So, I guess what I am saying is that ALE and PC-ALE could provide much of what the experimental digital hams want. It is not an key- board rag-chew mode but could be used to set-up such rag-chews. It DOES appear to be a reliable mode/system for traffic handling and emergency situations. Andy K3UK Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Re: Another look at ALE
Title: RE: [digitalradio] Re: Another look at ALE There has been some discussion about what mode does what and what is needed/desired. We have had a little discussion on what the problems were during Katrina with digital communications. During hurricanes Katrina and Rita, I worked with a disaster relief group and operated as their HF net control station and a participating station. Our network in Katrina ran from the Mississippi Gulf Coast up to Atlanta back to Louisiana including New Orleans, Batron Rouge, Hammons, Bogalusa and north, Alexandria, Lafayette, Beaumont Texas, Dallas and San Antonio Texas. Most of the time we would have liked to use a keyboard-to-keyboard mode...probably 60% of the time. 20% to 30% of the time Sideband Voice was Ok. But there was 10% of the time when we would have liked to be able to send a rather large data file from our Dallas, San Antonio or Atlanta stations to all of our stations. In many instances conditions were so poor that voice communications didn't work very well at all. Most of the time when sending smaller data packages, reading them by voice worked Ok; however, we have many request for repeats and we had to relay many times. We only operated on three frequencies and primarily on 40 and 75 meters since propagation programs showed that these were the best frequencies to use at the time. I might mention that our net operations and net control stations operate much like a state or local EOC (I worked many years in a large city EOC). When I think of what I would like in a mode to support the type of communications I was involved in (and I think most of the disaster relief agencies such as the Red Cross, Salvation Army and the like), I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robust enough to work right down in the noise. As far as frequency selection, when you only have 2 bands that will support propagation and use only one frequency on each band, channel selection is not a problem. An automatic call ability, such as SELCALL, would be very nice to have. Most of the other capabilities I hear about are nice but not really needed. I believe that the type of operations I was involved in, and will be again this hurricane season, are useful in passing many if not most types of traffic on HF. Thanks and 73, Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:digitalradio@yahoogroups.com]On Behalf Of Andrew O'Brien Sent: Tuesday, March 14, 2006 3:37 PM To: digitalradio@yahoogroups.com Subject: [digitalradio] Re: Another look at ALE --- In digitalradio@yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Andy, Are you talking about Automatic Link Establsihment capability to connect to stations or the service messaging protocol of ALE just to send text with? Good question. I started my thoughts in reaction to all the interest here in PAX2, and previously in Olivia. It seems to me that many on this list enjoy the experiments in finding a digital mode that performs well in marginal situations. There are also those that like the ability to beacon and use the radio for digital message handling. ALE , or at least the use of ALE in PC-ALE, appears to provide most of this. I no ALE expert, and only use it on a basic amateur transceiver, but ALE linking , use of trace/soundings, and use of propagation data , appears to help the ham in working under marginal conditions . The digital message ability of PC-ALE appears to provide some of the functions that PAX2 does. I have not really tested how ALE messages work under poor conditions. So, I guess what I am saying is that ALE and PC-ALE could provide much of what the experimental digital hams want. It is not an key- board rag-chew mode but could be used to set-up such rag-chews. It DOES appear to be a reliable mode/system for traffic handling and emergency situations. Andy K3UK Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) SPONSORED LINKS Ham radio Craft hobby Hobby
Re: [digitalradio] Re: Another look at ALE
Walt, What you are describing sounds very close to MT-63. 73, Rick, KV9U DuBose Walt Civ AETC CONS/LGCA wrote: There has been some discussion about what mode does what and what is needed/desired. We have had a little discussion on what the problems were during Katrina with digital communications. During hurricanes Katrina and Rita, I worked with a disaster relief group and operated as their HF net control station and a participating station. Our network in Katrina ran from the Mississippi Gulf Coast up to Atlanta back to Louisiana including New Orleans, Batron Rouge, Hammons, Bogalusa and north, Alexandria, Lafayette, Beaumont Texas, Dallas and San Antonio Texas. Most of the time we would have liked to use a keyboard-to-keyboard mode...probably 60% of the time. 20% to 30% of the time Sideband Voice was Ok. But there was 10% of the time when we would have liked to be able to send a rather large data file from our Dallas, San Antonio or Atlanta stations to all of our stations. In many instances conditions were so poor that voice communications didn't work very well at all. Most of the time when sending smaller data packages, reading them by voice worked Ok; however, we have many request for repeats and we had to relay many times. We only operated on three frequencies and primarily on 40 and 75 meters since propagation programs showed that these were the best frequencies to use at the time. I might mention that our net operations and net control stations operate much like a state or local EOC (I worked many years in a large city EOC). When I think of what I would like in a mode to support the type of communications I was involved in (and I think most of the disaster relief agencies such as the Red Cross, Salvation Army and the like), I would like a robust keyboard-to-keyboard mode that would accept typing at about 50-60 WPM. Also a robust mode that could send data files at 200 WPM and be robust enough to work right down in the noise. As far as frequency selection, when you only have 2 bands that will support propagation and use only one frequency on each band, channel selection is not a problem. An automatic call ability, such as SELCALL, would be very nice to have. Most of the other capabilities I hear about are nice but not really needed. I believe that the type of operations I was involved in, and will be again this hurricane season, are useful in passing many if not most types of traffic on HF. Thanks and 73, Walt/K5YFW Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] Re: Another look at ALE
I'll be monitoring 7065 USB for ALE tonight until around 0500 UTC. If you want to play around with Indivdual Calls via ALE (as opposed to Net Calls), we can experiement up a few KCs from 7065 after making a link. Andy K3UK Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] Re: Another look at ALE
Here is a snippet from Bonnie and the HFLINK group This afternoon, I heard John K6ERO calling on the 20m sounding channel, 14109.5kHz USB. I linked with him there and sent an AMD: QSY SSB VOICE THIS BAND. Then I called him on 14346 and we linked there. We talked for a while on voice SSB. The band was also open to the Pacific at that time. That above is what makes ALE so interesting, combining digital messages with software controlled radios etc. Andy K3UK Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
