[digitalradio] Re: DominoEX On VHF FM
Good morning all... This has been interesting me since I read about it in QST last year. I, too, have been looking to do some experimenting with this mode. Last year, I briefly tested this by heading to my Churchabout 3.5 miles away. I brought along my TINY Sony Vaio and my IC-2AT...and then set my FT-817 in receive with DominoEX-8. With 100 mW, I had nearly solid print from the old 2AT and a rubber-duckie antenna. With better antennas, one would think that significantly better distances could be accomplished. Too bad more don't experiment like this. 73, John KB2HSH --- In digitalradio@yahoogroups.com, JonP jpere...@... wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ
Re: [digitalradio] Re: DominoEX On VHF FM
That sounds like fun, and useful too. ve3bdr in kanuckistan From: kb2hsh Sent: Tuesday, July 20, 2010 10:16 AM To: digitalradio@yahoogroups.com Subject: [digitalradio] Re: DominoEX On VHF FM Good morning all... This has been interesting me since I read about it in QST last year. I, too, have been looking to do some experimenting with this mode. Last year, I briefly tested this by heading to my Churchabout 3.5 miles away. I brought along my TINY Sony Vaio and my IC-2AT...and then set my FT-817 in receive with DominoEX-8. With 100 mW, I had nearly solid print from the old 2AT and a rubber-duckie antenna. With better antennas, one would think that significantly better distances could be accomplished. Too bad more don't experiment like this. 73, John KB2HSH --- In digitalradio@yahoogroups.com, JonP jpere...@... wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.839 / Virus Database: 271.1.1/3017 - Release Date: 07/20/10 02:36:00
[digitalradio] Re: DominoEX On VHF FM
How will RMS Express running WINMOR in either SSB mode or FM mode fit in between this comparisons? Can even be adjusted to run through repeaters. Can run Peer to Peer or to a WInlink RMS WINMOR. I am looking forward to learning about pros an cons. 73 de la7um Finn --- In digitalradio@yahoogroups.com, KH6TY kh...@... wrote: Dave, I forgot to point out that we use Contestia 64/1000 on SSB, not FM, for that 200 mile path. When using FM, DominoEx works just as well, but of course, the overall range is less on FM. Essentially, if you can work a VHF or UHF station on SSB phone, you can work the same station on FM using DominoEx 4 (the most sensitive DominoEx variation). This was the subject of my presentation to the Southeastern VHF Society in April of last year, and we have since proven that over and over again. The difference is that the data rate of DominoEx 4 compared to SSB phone is much slower (assuming an average speaking speed of 200 wpm). However, on tropospheric scatter UHF paths, DominoEx does not survive at all and only Contestia or Olivia (half the speed of Contestia) get through, when even moderately strong SSB phone signals are so distorted by Doppler spreading that they are not understandable. This is true on probably 80% of our morning schedules on 432 MHz over 200 mile paths when there is no propagation enhancement. 73, Skip KH6TY On 7/19/2010 8:35 PM, KB3FXI wrote: Interesting suggestions, Skip. We're hoping to be installing UHF and VHF vertical yagi's at the Skyview Radio Society before winter sets in. I'll be sure to do some weak signal work with the DominoEx 8 as you suggest. -Dave, KB3FXI --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, KH6TY kh6ty@ wrote: The reason to use DominoEx is only for FM DX communications. It is slower than MT63, but much more sensitive, so you still get good copy way below limiting and quieting. For that reason, on our local FM digital net, we use DominoEx 8 and with horizontally polarized antennas, include everyone in a range of 35 miles. I suggest trying MT63-2000, and if some stations cannot copy, drop down in speed to MT63-1000, and if necessary, drop down to MT63-500. Then if you still have problems with some stations not copying, go to DominoEx 8. If any station is below limiting, which is quite possible at 25 miles using low verticals, MT63 may not work. On UHF, where Doppler shift and Doppler spreading is a major problem with SSB voice, we use Contestia 64-1000, which works very well on 200 miles paths. 73, Skip KH6TY On 7/19/2010 7:58 PM, KB3FXI wrote: Jon, Here in WPA we've adopted MT63 2k long (64 bit) interleave as our standard. The mode is very wide (2000hz) but fits very nicely inside the typical FM transceiver and repeater audio passbands. Here's some of the big advantages of MT63 2k long on FM: -Massive amount of FEC (forward error correction) and interleaving provides perfect copy, even under horrendous simplex conditions and weak signals into repeaters (it even barrels through short drop-outs and heavy noise with weak stations into our local UHF repeater) -There's no need to have to tune on the waterfall as all MT63 submodes in FLDIGI are fixed at a bottom waterfall frequency of 500hz (2k long goes from 500 - 2500 on the waterfall) -WPM rate is about 200wpm -Works fine using only a hand mic on the computer speaker and the computer mic somewhere in the vicinity of the received audio from the transceiver We run over UHF/VHF traditional voice repeaters and simplex frequencies with great success on our net every week... even with first time users. Please give it a shot and let us know how you make out. Also, make sure your ops do a proper sound card calibration. You only have to do this once, unless you change your sound card or switch to a USB mic. Here's a video I made on that subject of calibration using CheckSR.exe and FLDIGI: http://www.utipu.com/app/tip/id/9382/ -Dave, KB3FXI www.wpaNBEMS.org --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com mailto:digitalradio%40yahoogroups.com, JonP jperelst@ wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes
[digitalradio] Re: DominoEX On VHF FM
Jon, Here in WPA we've adopted MT63 2k long (64 bit) interleave as our standard. The mode is very wide (2000hz) but fits very nicely inside the typical FM transceiver and repeater audio passbands. Here's some of the big advantages of MT63 2k long on FM: -Massive amount of FEC (forward error correction) and interleaving provides perfect copy, even under horrendous simplex conditions and weak signals into repeaters (it even barrels through short drop-outs and heavy noise with weak stations into our local UHF repeater) -There's no need to have to tune on the waterfall as all MT63 submodes in FLDIGI are fixed at a bottom waterfall frequency of 500hz (2k long goes from 500 - 2500 on the waterfall) -WPM rate is about 200wpm -Works fine using only a hand mic on the computer speaker and the computer mic somewhere in the vicinity of the received audio from the transceiver We run over UHF/VHF traditional voice repeaters and simplex frequencies with great success on our net every week... even with first time users. Please give it a shot and let us know how you make out. Also, make sure your ops do a proper sound card calibration. You only have to do this once, unless you change your sound card or switch to a USB mic. Here's a video I made on that subject of calibration using CheckSR.exe and FLDIGI: http://www.utipu.com/app/tip/id/9382/ -Dave, KB3FXI www.wpaNBEMS.org --- In digitalradio@yahoogroups.com, JonP jpere...@... wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ
Re: [digitalradio] Re: DominoEX On VHF FM
The reason to use DominoEx is only for FM DX communications. It is slower than MT63, but much more sensitive, so you still get good copy way below limiting and quieting. For that reason, on our local FM digital net, we use DominoEx 8 and with horizontally polarized antennas, include everyone in a range of 35 miles. I suggest trying MT63-2000, and if some stations cannot copy, drop down in speed to MT63-1000, and if necessary, drop down to MT63-500. Then if you still have problems with some stations not copying, go to DominoEx 8. If any station is below limiting, which is quite possible at 25 miles using low verticals, MT63 may not work. On UHF, where Doppler shift and Doppler spreading is a major problem with SSB voice, we use Contestia 64-1000, which works very well on 200 miles paths. 73, Skip KH6TY On 7/19/2010 7:58 PM, KB3FXI wrote: Jon, Here in WPA we've adopted MT63 2k long (64 bit) interleave as our standard. The mode is very wide (2000hz) but fits very nicely inside the typical FM transceiver and repeater audio passbands. Here's some of the big advantages of MT63 2k long on FM: -Massive amount of FEC (forward error correction) and interleaving provides perfect copy, even under horrendous simplex conditions and weak signals into repeaters (it even barrels through short drop-outs and heavy noise with weak stations into our local UHF repeater) -There's no need to have to tune on the waterfall as all MT63 submodes in FLDIGI are fixed at a bottom waterfall frequency of 500hz (2k long goes from 500 - 2500 on the waterfall) -WPM rate is about 200wpm -Works fine using only a hand mic on the computer speaker and the computer mic somewhere in the vicinity of the received audio from the transceiver We run over UHF/VHF traditional voice repeaters and simplex frequencies with great success on our net every week... even with first time users. Please give it a shot and let us know how you make out. Also, make sure your ops do a proper sound card calibration. You only have to do this once, unless you change your sound card or switch to a USB mic. Here's a video I made on that subject of calibration using CheckSR.exe and FLDIGI: http://www.utipu.com/app/tip/id/9382/ -Dave, KB3FXI www.wpaNBEMS.org --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, JonP jpere...@... wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ
[digitalradio] Re: DominoEX On VHF FM
Interesting suggestions, Skip. We're hoping to be installing UHF and VHF vertical yagi's at the Skyview Radio Society before winter sets in. I'll be sure to do some weak signal work with the DominoEx 8 as you suggest. -Dave, KB3FXI --- In digitalradio@yahoogroups.com, KH6TY kh...@... wrote: The reason to use DominoEx is only for FM DX communications. It is slower than MT63, but much more sensitive, so you still get good copy way below limiting and quieting. For that reason, on our local FM digital net, we use DominoEx 8 and with horizontally polarized antennas, include everyone in a range of 35 miles. I suggest trying MT63-2000, and if some stations cannot copy, drop down in speed to MT63-1000, and if necessary, drop down to MT63-500. Then if you still have problems with some stations not copying, go to DominoEx 8. If any station is below limiting, which is quite possible at 25 miles using low verticals, MT63 may not work. On UHF, where Doppler shift and Doppler spreading is a major problem with SSB voice, we use Contestia 64-1000, which works very well on 200 miles paths. 73, Skip KH6TY On 7/19/2010 7:58 PM, KB3FXI wrote: Jon, Here in WPA we've adopted MT63 2k long (64 bit) interleave as our standard. The mode is very wide (2000hz) but fits very nicely inside the typical FM transceiver and repeater audio passbands. Here's some of the big advantages of MT63 2k long on FM: -Massive amount of FEC (forward error correction) and interleaving provides perfect copy, even under horrendous simplex conditions and weak signals into repeaters (it even barrels through short drop-outs and heavy noise with weak stations into our local UHF repeater) -There's no need to have to tune on the waterfall as all MT63 submodes in FLDIGI are fixed at a bottom waterfall frequency of 500hz (2k long goes from 500 - 2500 on the waterfall) -WPM rate is about 200wpm -Works fine using only a hand mic on the computer speaker and the computer mic somewhere in the vicinity of the received audio from the transceiver We run over UHF/VHF traditional voice repeaters and simplex frequencies with great success on our net every week... even with first time users. Please give it a shot and let us know how you make out. Also, make sure your ops do a proper sound card calibration. You only have to do this once, unless you change your sound card or switch to a USB mic. Here's a video I made on that subject of calibration using CheckSR.exe and FLDIGI: http://www.utipu.com/app/tip/id/9382/ -Dave, KB3FXI www.wpaNBEMS.org --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, JonP jperelst@ wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ
Re: [digitalradio] Re: DominoEX On VHF FM
Dave, I forgot to point out that we use Contestia 64/1000 on SSB, not FM, for that 200 mile path. When using FM, DominoEx works just as well, but of course, the overall range is less on FM. Essentially, if you can work a VHF or UHF station on SSB phone, you can work the same station on FM using DominoEx 4 (the most sensitive DominoEx variation). This was the subject of my presentation to the Southeastern VHF Society in April of last year, and we have since proven that over and over again. The difference is that the data rate of DominoEx 4 compared to SSB phone is much slower (assuming an average speaking speed of 200 wpm). However, on tropospheric scatter UHF paths, DominoEx does not survive at all and only Contestia or Olivia (half the speed of Contestia) get through, when even moderately strong SSB phone signals are so distorted by Doppler spreading that they are not understandable. This is true on probably 80% of our morning schedules on 432 MHz over 200 mile paths when there is no propagation enhancement. 73, Skip KH6TY On 7/19/2010 8:35 PM, KB3FXI wrote: Interesting suggestions, Skip. We're hoping to be installing UHF and VHF vertical yagi's at the Skyview Radio Society before winter sets in. I'll be sure to do some weak signal work with the DominoEx 8 as you suggest. -Dave, KB3FXI --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, KH6TY kh...@... wrote: The reason to use DominoEx is only for FM DX communications. It is slower than MT63, but much more sensitive, so you still get good copy way below limiting and quieting. For that reason, on our local FM digital net, we use DominoEx 8 and with horizontally polarized antennas, include everyone in a range of 35 miles. I suggest trying MT63-2000, and if some stations cannot copy, drop down in speed to MT63-1000, and if necessary, drop down to MT63-500. Then if you still have problems with some stations not copying, go to DominoEx 8. If any station is below limiting, which is quite possible at 25 miles using low verticals, MT63 may not work. On UHF, where Doppler shift and Doppler spreading is a major problem with SSB voice, we use Contestia 64-1000, which works very well on 200 miles paths. 73, Skip KH6TY On 7/19/2010 7:58 PM, KB3FXI wrote: Jon, Here in WPA we've adopted MT63 2k long (64 bit) interleave as our standard. The mode is very wide (2000hz) but fits very nicely inside the typical FM transceiver and repeater audio passbands. Here's some of the big advantages of MT63 2k long on FM: -Massive amount of FEC (forward error correction) and interleaving provides perfect copy, even under horrendous simplex conditions and weak signals into repeaters (it even barrels through short drop-outs and heavy noise with weak stations into our local UHF repeater) -There's no need to have to tune on the waterfall as all MT63 submodes in FLDIGI are fixed at a bottom waterfall frequency of 500hz (2k long goes from 500 - 2500 on the waterfall) -WPM rate is about 200wpm -Works fine using only a hand mic on the computer speaker and the computer mic somewhere in the vicinity of the received audio from the transceiver We run over UHF/VHF traditional voice repeaters and simplex frequencies with great success on our net every week... even with first time users. Please give it a shot and let us know how you make out. Also, make sure your ops do a proper sound card calibration. You only have to do this once, unless you change your sound card or switch to a USB mic. Here's a video I made on that subject of calibration using CheckSR.exe and FLDIGI: http://www.utipu.com/app/tip/id/9382/ -Dave, KB3FXI www.wpaNBEMS.org --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com mailto:digitalradio%40yahoogroups.com, JonP jperelst@ wrote: I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time. I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the Linux or Apple and D*Star messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM
