Re: [digitalradio] Digital Propagation Tests
I think that for the speed, MT-63 can be OK. But not that great with difficult conditions. A lot of modes will work find with good paths. I suspect that they have reasonably strong signals. MT-63 just does not reach down into the noise as some other modes and I have tested it many times under many conditions to reach that conclusion. The MIL-STD 188-110 single tone modem is something that I would like to test. It is very odd to me why we are not hearing at least a few who are doing this. I very much want to see how well it works compared to other modes. I realize it is a very wide mode since it was designed to take up most of a full voice bandwidth for commercial/government use. Just because it always runs at 2400 baud symbol rate and is illegal to use here in the U.S. on the text digital portions of the bands does not mean it can not be used in the voice/image portions of the bands to at least send pictures. Why do you suppose that it is not being at least tested? I have asked this many times and have yet to have one person respond with their experiences. 73, Rick, KV9U Steve Hajducek wrote: > Hi Rick, > > You obviously do not use MT-63 to pass book traffic on a daily basis > on NVIS paths, fore if you did your opinion would be completely > different and if you don't believe me, just ask any MARS member that > is using a Sound Card based system these days and they will tell you > just how robust MT-63 is for an FEC protocol. > > As to MIL-STD-188-110 serial tone modem and associated protocols, > being as not only FEC but ARQ is provided and with data rates down to > 75bps, it is extremely robust, granted 75bps is rather slow, but it > just can not be stopped, 75bps is know as ROBUST mode by the way, > there is no PSK carrier frequency and its a psuedo spread spectrum > waveform within a 3Khz channel, even in MARS-ALE at 75bps its always > 3Khz as you can't diddle with the carrier and symbol rate which don't > exist as such at higher data rates. > > /s/ Steve, N2CKH > > At 05:51 PM 10/27/2007, you wrote: > >> Steve, >> >> If MT-63 is robust relative to MIL-STD-188-110, then the latter may not >> be all that robust! I do not find MT-63 to be all that robust, and it is >> not as sensitive as other modes since it does not work well into the noise. >> >> Do you have any real world amateur tests yet on the MIL-STD-188-110 >> modems using the PC-ALE software approach? >> >> I have tested this out on 6 meters and it seems to transmit OK. I don't >> have anyone close by with the capability to run the program who can also >> operate digital modes. >> >> Also, have you found anyone who has run this software on HF here in the >> U.S. in the voice/image portions of the bands? >> >> It has been several weeks and I have not received any response back from >> ARRL yet on my tentative submission to the FCC for an interpretation of >> these regulations. Perhaps some are holding back because they consider >> the modes not legal in the voice/image areas? My reading of the rules >> says that it should be proper to use this software. >> >> Do you (or anyone else) have any thoughts as to why these modes are not >> being at least tested on HF? >> >> 73, >> >> Rick, KV9U >> > > > >
Re: [digitalradio] Digital Propagation Tests
Hi Rick, You obviously do not use MT-63 to pass book traffic on a daily basis on NVIS paths, fore if you did your opinion would be completely different and if you don't believe me, just ask any MARS member that is using a Sound Card based system these days and they will tell you just how robust MT-63 is for an FEC protocol. As to MIL-STD-188-110 serial tone modem and associated protocols, being as not only FEC but ARQ is provided and with data rates down to 75bps, it is extremely robust, granted 75bps is rather slow, but it just can not be stopped, 75bps is know as ROBUST mode by the way, there is no PSK carrier frequency and its a psuedo spread spectrum waveform within a 3Khz channel, even in MARS-ALE at 75bps its always 3Khz as you can't diddle with the carrier and symbol rate which don't exist as such at higher data rates. /s/ Steve, N2CKH At 05:51 PM 10/27/2007, you wrote: >Steve, > >If MT-63 is robust relative to MIL-STD-188-110, then the latter may not >be all that robust! I do not find MT-63 to be all that robust, and it is >not as sensitive as other modes since it does not work well into the noise. > >Do you have any real world amateur tests yet on the MIL-STD-188-110 >modems using the PC-ALE software approach? > >I have tested this out on 6 meters and it seems to transmit OK. I don't >have anyone close by with the capability to run the program who can also >operate digital modes. > >Also, have you found anyone who has run this software on HF here in the >U.S. in the voice/image portions of the bands? > >It has been several weeks and I have not received any response back from >ARRL yet on my tentative submission to the FCC for an interpretation of >these regulations. Perhaps some are holding back because they consider >the modes not legal in the voice/image areas? My reading of the rules >says that it should be proper to use this software. > >Do you (or anyone else) have any thoughts as to why these modes are not >being at least tested on HF? > >73, > >Rick, KV9U
Re: [digitalradio] Digital Propagation Tests
Steve, If MT-63 is robust relative to MIL-STD-188-110, then the latter may not be all that robust! I do not find MT-63 to be all that robust, and it is not as sensitive as other modes since it does not work well into the noise. Do you have any real world amateur tests yet on the MIL-STD-188-110 modems using the PC-ALE software approach? I have tested this out on 6 meters and it seems to transmit OK. I don't have anyone close by with the capability to run the program who can also operate digital modes. Also, have you found anyone who has run this software on HF here in the U.S. in the voice/image portions of the bands? It has been several weeks and I have not received any response back from ARRL yet on my tentative submission to the FCC for an interpretation of these regulations. Perhaps some are holding back because they consider the modes not legal in the voice/image areas? My reading of the rules says that it should be proper to use this software. Do you (or anyone else) have any thoughts as to why these modes are not being at least tested on HF? 73, Rick, KV9U Steve Hajducek wrote: > Hi Tony, > > Too bad you did not also run MT-63 at all three > modes for comparison. I can tell you that next to > the various 75bps Robust mode on the > MIL-STD-188-110/STANAG modem, its very robust. > However under such conditions nothing but an ARQ protocol will really suffice. > > /s/ Steve, N2CKH >
Re: [digitalradio] Digital Propagation Tests
Real attempts on 40 meters have had the same results for me. On 20 it works far better, almost perfect.. MT63 is robust but too slow, and "waving the carpet" leaves it dizzy. Being too slow, even slow doppler has a too high impact on it. Jose, CO2JA --- Tony escribió: > Hi Steve, > > > Too bad you did not also run MT-63 at all three modes for > > comparison. > > I did try MT63 at 2k, 1k and 500hz (squelch off). Copy was completely > garbled with the harsh path delay and frequency spread settings > used. I tried removing the AWGN noise channel from the simulator to > see if it was an SNR issue, but still no copy. > > Tony - K2MO __ Participe en Universidad 2008. 11 al 15 de febrero del 2008. Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.universidad2008.cu
Re: [digitalradio] Digital Propagation Tests
Hi Steve, >Too bad you did not also run MT-63 at all three modes for comparison. I did try MT63 at 2k, 1k and 500hz (squelch off). Copy was completely garbled with the harsh path delay and frequency spread settings used. I tried removing the AWGN noise channel from the simulator to see if it was an SNR issue, but still no copy. Tony - K2MO - Original Message - From: "Steve Hajducek" <[EMAIL PROTECTED]> To: Sent: Saturday, October 27, 2007 1:37 PM Subject: Re: [digitalradio] Digital Propagation Tests Hi Tony, Too bad you did not also run MT-63 at all three modes for comparison. I can tell you that next to the various 75bps Robust mode on the MIL-STD-188-110/STANAG modem, its very robust. However under such conditions nothing but an ARQ protocol will really suffice. /s/ Steve, N2CKH At 12:31 AM 10/27/2007, you wrote: >All, > >For what it's worth, I ran several digital modes through a >high-latitude >ionospheric path simulator and recorded the results. The signal spread >was set to 30Hz and path delay was 7 milliseconds. With these settings, >the audio sounds much llike the most extreme polar path distortion and >the simulator did a real number on throughput. > >Signal-to-noise (AWGN) was set at a threashold that allowed the most >robust mode to print at 90 percent. In this case, that mode was Olivia >1000/32. Although far from conclusive, mode performance seemed to >compare well with on-air experience under the most disturbed >conditions. > >See below... > >Tony K2MO > > > >OLIVIA 1000HZ / 32 TONE > >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG > >OLIVIA 500HZ / 16 TONE > >THE QUICK BROWN FO6 JUMPS OVE< THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUIMK LROWN FOX JUMPS OVEn THE LAZY DOG >QHA QUICK BROWN FOp JUMPS OVER THE LAZY DOG > >OLIVIA 500HZ / 8 TONE > >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICKRhWN ~ JUMPS OVER jELAZY UOG >THKUICK BROWN FOi JUMPS OVER THE cAZv >THF7yICK BROWN FO_ J$9=SGOVER THE LAZY DOG > >CONTESTIA 1000HZ / 32 TONE > >/THE QUICK BAOWN FOX J+M*S ,VER THE & ZJFDOG >$H 4.ICK B8OWN FOX JUMPS 5E QUIY<:A,OWN FONMATSR THE LAZY DOG >THE QUICK BROWN FOX J(LPS OVE0 TLE LAZY DOG > >CONTESTIA 500HZ / 16 TONE > >THE QUICK BROWN FOX JUMPS OV&U THE LXZ_ DJG >TME QUI/K BRON FOX JUM?S OVERTHE LAZY DOQ >TH' QUGCK BROWN G-C?JU/PS,OVFL5LE L"Z DOG >THE QUIKK BQOWN:#OX JUM!S OVERXTHE LAZT D5G > >CONTESTIA 500HZ / 8 TONE > >THE QUICK BROWN F#- T65IIRLI4L DJ! DO64I)(+ >QUICKCAH23DOX^6XMK-_,[EMAIL PROTECTED]" ,J<^' >OWN'C!5TWNTQV0GRSM9OT > >MFSK-16 > >u ÊICK BÀêe òt*ePÒct if'cÃlPøh vci]pdgeldt >N¢án i!i - ís=te.aOaÍC=iòYÃHE LAZY eeAxn1E >^Àn±uQ1yaPitvén iafDel²ePS uh ueo ^um P > >RTTY 170HZ SHIFT / 45 BAUD > >WAHXQAICC VBU IDGTX KMLDJLUDUSTHE KLARFBJMY >YHJNJ VBBBDQMBMPZX DFHPYU YLNKXK YHVEQQCPZWP >OGTYD QPPWX!99 8!=9 YLDACVRDJFDDJ6!5),?''? > >PSK-31 > > i R ® n waeaoo o- oeo yietotreo ieP >goe },iitE,ã re o $ree" o l i osehest >e n_ I t dvee ruiTa e do e ro D e r >e_n- § 3e o ti e- } dohItQ s-e ty >eottor eo1keo ele roetahe eeÀiefA seg > > > > > > > >Announce your digital presence via our Interactive Sked Page at >http://www.obriensweb.com/drsked/drsked.php > >Yahoo! Groups Links > > >
Re: [digitalradio] Digital Propagation Tests
Hi Tony, Too bad you did not also run MT-63 at all three modes for comparison. I can tell you that next to the various 75bps Robust mode on the MIL-STD-188-110/STANAG modem, its very robust. However under such conditions nothing but an ARQ protocol will really suffice. /s/ Steve, N2CKH At 12:31 AM 10/27/2007, you wrote: >All, > >For what it's worth, I ran several digital modes through a high-latitude >ionospheric path simulator and recorded the results. The signal spread >was set to 30Hz and path delay was 7 milliseconds. With these settings, >the audio sounds much llike the most extreme polar path distortion and >the simulator did a real number on throughput. > >Signal-to-noise (AWGN) was set at a threashold that allowed the most >robust mode to print at 90 percent. In this case, that mode was Olivia >1000/32. Although far from conclusive, mode performance seemed to >compare well with on-air experience under the most disturbed conditions. > >See below... > >Tony K2MO > > > >OLIVIA 1000HZ / 32 TONE > >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG > >OLIVIA 500HZ / 16 TONE > >THE QUICK BROWN FO6 JUMPS OVE< THE LAZY DOG >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUIMK LROWN FOX JUMPS OVEn THE LAZY DOG >QHA QUICK BROWN FOp JUMPS OVER THE LAZY DOG > >OLIVIA 500HZ / 8 TONE > >THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG >THE QUICKRhWN ~ JUMPS OVER jELAZY UOG >THKUICK BROWN FOi JUMPS OVER THE cAZv >THF7yICK BROWN FO_ J$9=SGOVER THE LAZY DOG > >CONTESTIA 1000HZ / 32 TONE > >/THE QUICK BAOWN FOX J+M*S ,VER THE & ZJFDOG >$H 4.ICK B8OWN FOX JUMPS 5E QUIY<:A,OWN FONMATSR THE LAZY DOG >THE QUICK BROWN FOX J(LPS OVE0 TLE LAZY DOG > >CONTESTIA 500HZ / 16 TONE > >THE QUICK BROWN FOX JUMPS OV&U THE LXZ_ DJG >TME QUI/K BRON FOX JUM?S OVERTHE LAZY DOQ >TH' QUGCK BROWN G-C?JU/PS,OVFL5LE L"Z DOG >THE QUIKK BQOWN:#OX JUM!S OVERXTHE LAZT D5G > >CONTESTIA 500HZ / 8 TONE > >THE QUICK BROWN F#- T65IIRLI4L DJ! DO64I)(+ >QUICKCAH23DOX^6XMK-_,[EMAIL PROTECTED]" ,J<^' >OWN'C!5TWNTQV0GRSM9OT > >MFSK-16 > >u ÊICK BÀêe òt*ePÒct if'cÃlPøh vci]pdgeldt >N¢án i!i - ís=te.aOaÍC=iòYÃHE LAZY eeAxn1E >^Àn±uQ1yaPitvén iafDel²ePS uh ueo ^um P > >RTTY 170HZ SHIFT / 45 BAUD > >WAHXQAICC VBU IDGTX KMLDJLUDUSTHE KLARFBJMY >YHJNJ VBBBDQMBMPZX DFHPYU YLNKXK YHVEQQCPZWP >OGTYD QPPWX!99 8!=9 YLDACVRDJFDDJ6!5),?''? > >PSK-31 > > i R ® n waeaoo o- oeo yietotreo ieP >goe },iitE,ã re o $ree" o l i osehest >e n_ I t dvee ruiTa e do e ro D e r >e_n- § 3e o ti e- } dohItQ s-e ty >eottor eo1keo ele roetahe eeÀiefA seg > > > > > > > >Announce your digital presence via our Interactive Sked Page at >http://www.obriensweb.com/drsked/drsked.php > >Yahoo! Groups Links > > >
[digitalradio] Digital Propagation Tests
All, For what it's worth, I ran several digital modes through a high-latitude ionospheric path simulator and recorded the results. The signal spread was set to 30Hz and path delay was 7 milliseconds. With these settings, the audio sounds much llike the most extreme polar path distortion and the simulator did a real number on throughput. Signal-to-noise (AWGN) was set at a threashold that allowed the most robust mode to print at 90 percent. In this case, that mode was Olivia 1000/32. Although far from conclusive, mode performance seemed to compare well with on-air experience under the most disturbed conditions. See below... Tony K2MO OLIVIA 1000HZ / 32 TONE THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG OLIVIA 500HZ / 16 TONE THE QUICK BROWN FO6 JUMPS OVE< THE LAZY DOG THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG THE QUIMK LROWN FOX JUMPS OVEn THE LAZY DOG QHA QUICK BROWN FOp JUMPS OVER THE LAZY DOG OLIVIA 500HZ / 8 TONE THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG THE QUICKRhWN ~ JUMPS OVER jELAZY UOG THKUICK BROWN FOi JUMPS OVER THE cAZv THF7yICK BROWN FO_ J$9=SGOVER THE LAZY DOG CONTESTIA 1000HZ / 32 TONE /THE QUICK BAOWN FOX J+M*S ,VER THE & ZJFDOG $H 4.ICK B8OWN FOX JUMPS