[Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Alternatively, there is a sound card based GMSK modem, that uses a Vellman K8055, Serial port, or URI for PTT/COR by Jonathan Naylor, G4KLX. See http://groups.yahoo.com/group/pcrepeatercontroller -- BTW, this design includes a plan for a combined Analog/D-STAR repeater as some here think would be a good idea. I've just joined this group, but I can confirm that the full dual mode version has been available for some time now. I changed my plans about how to implement it, and as a consequence GB3IN went fully dual mode using the same hardware for both FM and D-Star a number of months ago. GB3IN could possibly be the first software defined repeater in the world! All of my software is open source under the GPL. Jonathan G4KLX
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On Apr 6, 2010, at 8:45 PM, vr2 xvd wrote: Syetem Planed 1,xxx sites for full out door coverage . As the result it is double the site. They tried to increase the R.F power output. The field strength increase ,but only a bit change. It is because the TDMA format time slot overlap by distance multi path. Increased R.F Power seems result a lot of side band noise up to Ham Band, hi hi! Sounds like they need to hire an RF engineer or tech with more experience. Doubling power results in only 3dB of gain. It's rarely useful if the sites can see the desired coverage area. TDMA and other digital formats that are time-sensitive can suffer from a number of problems. I recommend they read up on Group Delay and talk to some data engineers. It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? One of the ways they could have protected themselves would have been to demand a particular coverage area be RF engineered PRIOR to installation of the system, and a contractual obligation back to the manufacturer, system installer, or both that THEY cover any costs involved in fixing it. That would have resulted in a much more accurate RF engineering assessment of the system requirements before turning it on and finding out that it did not cover where it needed to. I'm just an Amateur and don't work in Public Safety radio, but I know that's what I would have requested... -- Nate Duehr, WY0X n...@natetech.com
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
There are several. Harris- OpenSky, P25 Phase 2 are currently being deployed, and Iden ( Nextel ) Motorola has a version for municipals. I do not know if anyone ever built it but I saw it on proposals a few years back. It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? -- Nate Duehr, WY0X n...@natetech.com mailto:nate%40natetech.com Welcome http://us.ard.yahoo.com/SIG=15o3dc40l/M=493064.13814537.13965224.10835568/D =groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5 fb6cdd9016b/B=cEt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=604 2764/R=0/SIG=11jbo19n3/*http:/advision.webevents.yahoo.com/momconnection to Mom Connection! Share stories, news and more with moms like you. Image removed by sender. _ Hobbies http://us.ard.yahoo.com/SIG=15ogdepgv/M=493064.14012770.13963757.13298430/D =groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5 fb6cdd9016b/B=cUt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=601 5306/R=0/SIG=11vlkvigg/*http:/advision.webevents.yahoo.com/hobbiesandactivit ieszone/ Activities Zone: Find others who share your passions! Explore new interests. Image removed by sender. http://groups.yahoo.com/;_ylc=X3oDMTJjOG84dGViBF9TAzk3MzU5NzE0BGdycElkAzEwN DE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDZ2ZwBHN0aW1lAzEyNzA2MjE2OTc- Image removed by sender. Yahoo! Groups Switch to: mailto:repeater-builder-traditio...@yahoogroups.com?subject=change%20delive ry%20Format:%20Traditional Text-Only, mailto:repeater-builder-dig...@yahoogroups.com?subject=email%20delivery:%20 Digest Daily Digest . mailto:repeater-builder-unsubscr...@yahoogroups.com?subject=unsubscribe Unsubscribe . http://docs.yahoo.com/info/terms/ Terms of Use . Image removed by sender. image001.jpgimage002.jpg
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On 4/7/2010 2:28 AM, Nate Duehr wrote: It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? As Doug said, Harris (formerly M/A-Com) has Open Sky, 4-slot TDMA. P25 phase II will be TDMA as soon as they settle on the format... Most mfg's have gear ready to go with just a flash upgrade. Mototrbo and Kenwood/Icom Nexedge are both TDMA as well. And actually, since TDMA by definition has more then one talk path, it is inherently a trunked system, when you think about it. Jim
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Don't forget Tetra, which is huge in Europe... 73 de Darren G7LWT On 7 April 2010 13:11, Doug Bade k...@thebades.net wrote: There are several. Harris- OpenSky, P25 Phase 2 are currently being deployed, and Iden ( Nextel ) Motorola has a version for municipals. I do not know if anyone ever built it but I saw it on proposals a few years back. It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? -- Nate Duehr, WY0X n...@natetech.com nate%40natetech.com *Welcome to Mom Connection! Share stories, news and more with moms like you.http://us.ard.yahoo.com/SIG=15o3dc40l/M=493064.13814537.13965224.10835568/D=groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5fb6cdd9016b/B=cEt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=6042764/R=0/SIG=11jbo19n3/*http:/advision.webevents.yahoo.com/momconnection * *[image: Image removed by sender.]*** * -- * *Hobbies Activities Zone: Find others who share your passions! Explore new interests.http://us.ard.yahoo.com/SIG=15ogdepgv/M=493064.14012770.13963757.13298430/D=groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5fb6cdd9016b/B=cUt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=6015306/R=0/SIG=11vlkvigg/*http:/advision.webevents.yahoo.com/hobbiesandactivitieszone/ * *[image: Image removed by sender.]*** [image: Image removed by sender. Yahoo! Groups]http://groups.yahoo.com/;_ylc=X3oDMTJjOG84dGViBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDZ2ZwBHN0aW1lAzEyNzA2MjE2OTc- Switch to: Text-Onlyrepeater-builder-traditio...@yahoogroups.com?subject=change%20delivery%20format:%20Traditional, Daily Digestrepeater-builder-dig...@yahoogroups.com?subject=email%20delivery:%20Digest• Unsubscriberepeater-builder-unsubscr...@yahoogroups.com?subject=unsubscribe• Terms of Use http://docs.yahoo.com/info/terms/ . [image: Image removed by sender.] image002.jpgimage001.jpg
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On Apr 7, 2010, at 8:07 AM, wd8chl wrote: On 4/7/2010 2:28 AM, Nate Duehr wrote: It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? As Doug said, Harris (formerly M/A-Com) has Open Sky, 4-slot TDMA. P25 phase II will be TDMA as soon as they settle on the format... Most mfg's have gear ready to go with just a flash upgrade. Mototrbo and Kenwood/Icom Nexedge are both TDMA as well. And actually, since TDMA by definition has more then one talk path, it is inherently a trunked system, when you think about it. Yep all understood. My point was, I haven't seen any of those DEPLOYED in a Public Safety environment yet, so I doubt his posting was accurate about whatever system he's talking about being TDMA... It's probably something else... P25 phase I, most likely. But I appreciate the info from you and Doug both. No worries there. It's kinda fun to watch this industry screw itself up, isn't it? I've already watched it for years in wireline... the wireless guys apparently didn't learn anything with the mess that CODECs and protocols have become on wireline, and want to duplicate it by not sticking to a few standards. An expensive game. :-) The difference is, at least wireline takes everything down to the common denominator of IP somewhere in the communications path, usually... even if I can't read the payload, I can almost always break into a circuit somewhere along the path and make sure the IP is flowing properly. (No jokes about I. P. Freeley now...) -- Nate Duehr, WY0X n...@natetech.com
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Yes, Tetra 4 slot TDMA over a 25Khz channel, Phase 1 P25 12.5Khz digital over a single channel, NXDN Kenwood Icom FDMA 6.25 KHz digital and DMR standard is TDMA digital over a 12.5khz channel witch is 6.25Khz. I wish Tetra was here in the USA but were too stupid to think we could follow of what every other country is using. Maybe in another 20 years, by that time Europe will have 8 slot TDMA and we will be using 4 slot, go figure. Mike _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Storer, Darren Sent: Wednesday, April 07, 2010 8:49 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) Don't forget Tetra, which is huge in Europe... 73 de Darren G7LWT On 7 April 2010 13:11, Doug Bade k...@thebades. mailto:k...@thebades.net net wrote: There are several. Harris- OpenSky, P25 Phase 2 are currently being deployed, and Iden ( Nextel ) Motorola has a version for municipals. I do not know if anyone ever built it but I saw it on proposals a few years back. It almost sounds like you're talking about a trunked (multi-site) system though, and I don't know of any trunked TDMA-based commercial offerings in the 2-way radio market. Anyone else heard of one? -- Nate Duehr, WY0X n...@natetech. mailto:nate%40natetech.com com Welcome to Mom Connection! Share stories, news and more with http://us.ard.yahoo.com/SIG=15o3dc40l/M=493064.13814537.13965224.10835568/D =groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5 fb6cdd9016b/B=cEt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=604 2764/R=0/SIG=11jbo19n3/*http:/advision.webevents.yahoo.com/momconnection moms like you. Image removed by sender. _ Hobbies http://us.ard.yahoo.com/SIG=15ogdepgv/M=493064.14012770.13963757.13298430/D =groups/S=1705063108:MKP1/Y=YAHOO/EXP=1270628897/L=c0e38d88-420e-11df-b597-5 fb6cdd9016b/B=cUt5A2KJiV0-/J=1270621697815987/K=fQ4TlPwyAsbwR0xV0iWe7Q/A=601 5306/R=0/SIG=11vlkvigg/*http:/advision.webevents.yahoo.com/hobbiesandactivit ieszone/ Activities Zone: Find others who share your passions! Explore new interests. Image removed by sender. http://groups.yahoo.com/;_ylc=X3oDMTJjOG84dGViBF9TAzk3MzU5NzE0BGdycElkAzEwN DE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDZ2ZwBHN0aW1lAzEyNzA2MjE2OTc- Image removed by sender. Yahoo! Groups Switch to: mailto:repeater-builder-traditio...@yahoogroups.com?subject=change%20delive ry%20Format:%20Traditional Text-Only, mailto:repeater-builder-dig...@yahoogroups.com?subject=email%20delivery:%20 Digest Daily Digest . mailto:repeater-builder-unsubscr...@yahoogroups.com?subject=unsubscribe Unsubscribe . http://docs.yahoo.com/info/terms/ Terms of Use . Image removed by sender. image001.jpgimage002.jpg
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On 4/7/2010 11:22 AM, Nate Duehr wrote: Yep all understood. My point was, I haven't seen any of those DEPLOYED in a Public Safety environment yet, so I doubt his posting was accurate about whatever system he's talking about being TDMA... It's probably something else... P25 phase I, most likely. Actually, believe it or not, they all have except P25 phase II, and only because it isn't finalized yet! But I appreciate the info from you and Doug both. No worries there. It's kinda fun to watch this industry screw itself up, isn't it? I've already watched it for years in wireline... the wireless guys apparently didn't learn anything with the mess that CODECs and protocols have become on wireline, and want to duplicate it by not sticking to a few standards. Heh-P25 started back-what-late 80's/early 90's? No wonder they got stuck in old tech! It was only a couple years after VSELP! An expensive game. :-) The difference is, at least wireline takes everything down to the common denominator of IP somewhere in the communications path, usually... even if I can't read the payload, I can almost always break into a circuit somewhere along the path and make sure the IP is flowing properly. (No jokes about I. P. Freeley now...) /me smacks head DOH!
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On 4/7/2010 11:47 AM, k7...@skybeam.com wrote: Yes, Tetra 4 slot TDMA over a 25Khz channel, Phase 1 P25 12.5Khz digital over a single channel, NXDN Kenwood Icom FDMA 6.25 KHz digital and DMR standard is TDMA digital over a 12.5khz channel witch is 6.25Khz. I wish Tetra was here in the USA but were too stupid to think we could follow of what every other country is using. Maybe in another 20 years, by that time Europe will have 8 slot TDMA and we will be using 4 slot, go figure. Yeah, Tetra is a good format. The 'official' line on why you don't see it in the US (yet) is that propagation delays prevent a user from going beyond a certain distance from a site (which is true), and that that distance is rather short, requiring so many sites it would be impractical out in the sparsely populated parts of the west (with a 7 call you probably know what I mean). Europe doesn't have that problem too much. Yes, there is licensing issues here in the states though. Unlike P25, where about the only licensing a mfg has to contend with is DVSI (which hits everyone on equally hard), Motorola has some of the rights to Tetra, and they have until recently been reluctant to license it in the US. Now there is a group getting Tetra available in the US, and you may see some systems in 5 years or so. It'll be good for an urban area, but you won't see it much outside of big cities. It would be a bad choice for a state-wide system. Except maybe in RI. Course I don't think 700/800/900 is a good choice for a state-wide system anyway...
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Yep, were all aware of the issues here in the USA. On my commercial TDMA system I did a test 75miles away from the site with a portable and get back into the site with no problem. Way out of the FCC license but works great. Mike _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of wd8chl Sent: Wednesday, April 07, 2010 12:57 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) On 4/7/2010 11:47 AM, k7...@skybeam. mailto:k7pfj%40skybeam.com com wrote: Yes, Tetra 4 slot TDMA over a 25Khz channel, Phase 1 P25 12.5Khz digital over a single channel, NXDN Kenwood Icom FDMA 6.25 KHz digital and DMR standard is TDMA digital over a 12.5khz channel witch is 6.25Khz. I wish Tetra was here in the USA but were too stupid to think we could follow of what every other country is using. Maybe in another 20 years, by that time Europe will have 8 slot TDMA and we will be using 4 slot, go figure. Yeah, Tetra is a good format. The 'official' line on why you don't see it in the US (yet) is that propagation delays prevent a user from going beyond a certain distance from a site (which is true), and that that distance is rather short, requiring so many sites it would be impractical out in the sparsely populated parts of the west (with a 7 call you probably know what I mean). Europe doesn't have that problem too much. Yes, there is licensing issues here in the states though. Unlike P25, where about the only licensing a mfg has to contend with is DVSI (which hits everyone on equally hard), Motorola has some of the rights to Tetra, and they have until recently been reluctant to license it in the US. Now there is a group getting Tetra available in the US, and you may see some systems in 5 years or so. It'll be good for an urban area, but you won't see it much outside of big cities. It would be a bad choice for a state-wide system. Except maybe in RI. Course I don't think 700/800/900 is a good choice for a state-wide system anyway...
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On 4/7/2010 3:34 PM, k7...@skybeam.com wrote: Yep, were all aware of the issues here in the USA. On my commercial TDMA system I did a test 75miles away from the site with a portable and get back into the site with no problem. Way out of the FCC license but works great. Mike I guess it varies from format to format how far you can get without issuesI need to learn more...
[Repeater-Builder] Re: D-Star (Protocol and Repeaters)
In fact there are defined tests for real world performance of the various formats [with the exception of the amateur D-Star format] The commercial land mobile industry has great interest in understanding the operational characteristics of all of the current and emerging formats and protocols, including how each performs in the real world - on its own and while sharing the spectrum with other systems of the same or different formats. Consequently, for a number of years, the TIA [Telecommunications Industry Association] has had a working group studying the technology and developing standards and industry guidance documentation. For an overview of these TIA documents, do a Google search for: W09-olson.ppt - --- In Repeater-Builder@yahoogroups.com, Nate Duehr n...@... wrote: ... ... You will be spending a lot of time field testing to find out. There's no standard tests available for anything further than signal strength. ...
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Dear sirs, Thank very much for the information. Yes, it is difficult to say which one will better than other. For me/my team we get intend to know more on it before start the project. I heard a story that some where police digital radio system use TDMA format. Syetem Planed 1,xxx sites for full out door coverage . As the result it is double the site. They tried to increase the R.F power output. The field strength increase ,but only a bit change. It is because the TDMA format time slot overlap by distance multi path. Increased R.F Power seems result a lot of side band noise up to Ham Band, hi hi! Back to the Ham digital voice repeater ,due mode is a must . So D-star seems not matchat the moment, but its setup cost within our target. Second hand Mototrbo also meet the budget.But it is TDMA format. P25 cost a lot no ham use here. The above a my personal point of views ,we intend to find out / select and paln the next project. Digital Ham Repeater . Any suggestion comment are welcomes. VY73 de VR2XVD/W.L.Ho 7 Apr.10 On Wed, Apr 7, 2010 at 12:41 AM, nj902 wb0...@arrl.net wrote: In fact there are defined tests for real world performance of the various formats [with the exception of the amateur D-Star format] The commercial land mobile industry has great interest in understanding the operational characteristics of all of the current and emerging formats and protocols, including how each performs in the real world - on its own and while sharing the spectrum with other systems of the same or different formats. Consequently, for a number of years, the TIA [Telecommunications Industry Association] has had a working group studying the technology and developing standards and industry guidance documentation. For an overview of these TIA documents, do a Google search for: W09-olson.ppt -- --- In Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com, Nate Duehr n...@... wrote: ... ... You will be spending a lot of time field testing to find out. There's no standard tests available for anything further than signal strength. ... -- HKARA website : http://www.hkara.org.hk VR2XVD email : vr2...@yahoo.com,vr2...@gmail.com Please consider the environment before printing the email.
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On Apr 4, 2010, at 2:30 PM, John wrote: --- In Repeater-Builder@yahoogroups.com, Nate Duehr n...@... wrote: I like D-STAR as a not-very-well-designed first try and use it... but it's seriously technologically flawed. Some of that can be fixed... other things like the header information not being interlaced... -- Nate Duehr, WY0X n...@... Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. I believe if you'll look again, the callsign of the sending station is interlaced, but not RPT1/RPT2, and the destination address, which are the essential routing information. Plus, you're correct: Judging by the behavior, the repeater's don't look at that data or utilize it anyway. -- Nate Duehr, WY0X n...@natetech.com
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Okay. I've been reading with some interest the threads on D-STAR. There have been some very good points and some pretty amusing ones. P25 sounds interesting, but you will have to take note of the fact that it has not been widely accepted by the ham community. And considering that it (P25) is not compatible with D-STAR's AMBE codec, I doubt that it will be accepted by hams anytime soon. Who cares if D-STAR takes up repeater pairs that could be used for analog? Have you listened to the analog repeaters? They're mostly silent anyway. One comment that I read early on (and I don't recall who said this) was that in an emergency the analog users would not be able to access a D-STAR repeater. Yep, but so what? Do you really mean to tell me that each local area is covered by just one analog repeater? It just sounds to me like typical human behavior: resistance to change. There's a good friend of mine that was so ticked off at the institution of no-code hams. He calls them rif-raff. He operates almost exclusively on the CW sections of the HF bands to avoid the no-code folks. It's sad because there are a lot of no-code hams that are good operators and some are very technically knowledgeable. He might learn a thing or two from these folks. I wonder if the people in this group that are resisting D-STAR are missing the boat as well. Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog. Just my 2 cents. I'll go back to my corner now. John N3SPW _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Nate Duehr Sent: Monday, April 05, 2010 4:01 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) On Apr 4, 2010, at 2:30 PM, John wrote: --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Nate Duehr n...@... wrote: I like D-STAR as a not-very-well-designed first try and use it... but it's seriously technologically flawed. Some of that can be fixed... other things like the header information not being interlaced... -- Nate Duehr, WY0X n...@... Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. I believe if you'll look again, the callsign of the sending station is interlaced, but not RPT1/RPT2, and the destination address, which are the essential routing information. Plus, you're correct: Judging by the behavior, the repeater's don't look at that data or utilize it anyway. -- Nate Duehr, WY0X n...@natetech. mailto:nate%40natetech.com com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.800 / Virus Database: 271.1.1/2791 - Release Date: 04/04/10 14:32:00
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
John; There is indeed resistance to change. there are factions even in the D-Star Camp. Control of the network is being wrestled about in 2 separate networks that split. Be that as it may . We have the luxury of taking advantage of some really impressive reverse engineering that has been going on and does allow for adding an adapter to a suitable repeater to make it handle digital voice.. with D-Star voice protocols. For what many analog controllers cost. or less. Folks who want to make the digital move need to evaluate what they intend to do with their repeater. D-Star and P-25 have some ups and downs of each.. In P25 there are no simple implementations of wide area networking engineered into the CAI.. So routing calls to multiple repeaters is not easy. D-Star has routing in it but it is one of the complications many complain about as it is not real intuitive on how to program it all to get the desired results. Standalone Repeater options for either are fairly simple. At this point assuming you have a digital capable station.. I think it just became cheaper to do D-star conversion of that station. At least one author is working diligently to allow both analog and digital use of the Digital repeater modification he wrote and offers.. but it is in it's infancy.. Anyone who is currently building analog AllStar Link repeaters using a DMK URI already has the parts for a D-Star repeater .. assuming your TX and RX will handle GMSK data of your repeater.. This includes many Mastr II stations which seem to be a large portion of the amateur repeater world.. Cheap sound card interfaces..$ 10.00 each on Ebay or less can be used to build the controller when hooked to a PC with appropriate software.. I built my first Test D-Star repeater from 2 Icom F420 commercial mobiles and 2 USB Sound Fobs with a USB I/O controller to run the cor and PTT.. It works.. albeit basic. but is not the key ingredient now. Doug KD8B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of John Szwarc Sent: Monday, April 05, 2010 7:11 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) Okay. I've been reading with some interest the threads on D-STAR. There have been some very good points and some pretty amusing ones. P25 sounds interesting, but you will have to take note of the fact that it has not been widely accepted by the ham community. And considering that it (P25) is not compatible with D-STAR's AMBE codec, I doubt that it will be accepted by hams anytime soon. Who cares if D-STAR takes up repeater pairs that could be used for analog? Have you listened to the analog repeaters? They're mostly silent anyway. One comment that I read early on (and I don't recall who said this) was that in an emergency the analog users would not be able to access a D-STAR repeater. Yep, but so what? Do you really mean to tell me that each local area is covered by just one analog repeater? It just sounds to me like typical human behavior: resistance to change. There's a good friend of mine that was so ticked off at the institution of no-code hams. He calls them rif-raff. He operates almost exclusively on the CW sections of the HF bands to avoid the no-code folks. It's sad because there are a lot of no-code hams that are good operators and some are very technically knowledgeable. He might learn a thing or two from these folks. I wonder if the people in this group that are resisting D-STAR are missing the boat as well. Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog. Just my 2 cents. I'll go back to my corner now. John N3SPW _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Nate Duehr Sent: Monday, April 05, 2010 4:01 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Anyone who is currently building analog AllStar Link repeaters using a DMK URI already has the parts for a D-Star repeater .. assuming your TX and RX will handle GMSK data of your repeater.. This includes many Mastr II stations which seem to be a large portion of the amateur repeater world.. What are people doing about narrowbanding the RF hardware? There's no geo-spectral advantage to be gained by using D-Star/GMSK with a theoretical OBW of 6 kHz when the RF equipment is still wideband (mainly Rx IF, but also Tx must also be limited and LPF'ed). --- Jeff WN3A
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
There are P25 repeaters on the air. Granted, not as many as D-STAR (strictly talking about ham systems), but I know of nobody giving away P25 repeaters. Also, I bet there are more P25 receivers owned by hams than D-STAR since there are several scanners that decode P25, and only a few that decode D-STAR (not ironically, all made by Icom). Anyway, the point is not which format to use, but to make the systems as flexible as possible so they can be available in emergencies. Simply put, D-STAR is not as flexible as P25 since a P25 repeater can be made to pass P25 or analog. Granted, D-STAR does have some format benefits, but those could easily be added to P25 (or, the P25 benefits could be added to D-STAR, as has been discussed). There are also MotoTRBO repeaters in the ham bands, now. The more various formats you add to the mix, the less we will be likely to use them when they are needed. On the other hand, all the radios can use analog - making it the clear choice for emergency communications. Joe M. John Szwarc wrote: Okay. I've been reading with some interest the threads on D-STAR. There have been some very good points and some pretty amusing ones. P25 sounds interesting, but you will have to take note of the fact that it has not been widely accepted by the ham community. And considering that it (P25) is not compatible with D-STAR's AMBE codec, I doubt that it will be accepted by hams anytime soon. Who cares if D-STAR takes up repeater pairs that could be used for analog? Have you listened to the analog repeaters? They're mostly silent anyway. One comment that I read early on (and I don't recall who said this) was that in an emergency the analog users would not be able to access a D-STAR repeater. Yep, but so what? Do you really mean to tell me that each local area is covered by just one analog repeater? It just sounds to me like typical human behavior: resistance to change. There's a good friend of mine that was so ticked off at the institution of no-code hams. He calls them rif-raff. He operates almost exclusively on the CW sections of the HF bands to avoid the no-code folks. It's sad because there are a lot of no-code hams that are good operators and some are very technically knowledgeable. He might learn a thing or two from these folks. I wonder if the people in this group that are resisting D-STAR are missing the boat as well. Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog. Just my 2 cents. I'll go back to my corner now. John N3SPW *From:* Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] *On Behalf Of *Nate Duehr *Sent:* Monday, April 05, 2010 4:01 AM *To:* Repeater-Builder@yahoogroups.com *Subject:* Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) On Apr 4, 2010, at 2:30 PM, John wrote: --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com, Nate Duehr n...@... wrote: I like D-STAR as a not-very-well-designed first try and use it... but it's seriously technologically flawed. Some of that can be fixed... other things like the header information not being interlaced... -- Nate Duehr, WY0X n...@... Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. I believe if you'll look again, the callsign of the sending station is interlaced, but not RPT1/RPT2, and the destination address, which are the essential routing information. Plus, you're correct: Judging by the behavior, the repeater's don't look at that data or utilize it anyway. -- Nate Duehr, WY0X n...@natetech.com mailto:nate%40natetech.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.800 / Virus Database: 271.1.1/2791 - Release Date: 04/04/10 14:32:00
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On 4/5/2010 5:10 AM, John Szwarc wrote: Okay. I've been reading with some interest the threads on D-STAR. There have been some very good points and some pretty amusing ones. P25 sounds interesting, but you will have to take note of the fact that it has not been widely accepted by the ham community. And considering that it (P25) is not compatible with D-STAR's AMBE codec, I doubt that it will be accepted by hams anytime soon. Actually if history is any indicator, some hams will accept (operate) ALL of the new digital repeater modes. D-STAR will continue to be the most popular because you can buy it at the ham radio stores, even without any serious effort at real engineering/technical measurements and loaded with add-on software that Icom forgot... plus a lot of people scrambling to patch and fix Icom's really poor Gateway software. I've seen examples here on the list, and locally of ALL of these systems other than NXDN being deployed by hams already. I'm almost certain someone will respond and say they're trying that one out, too... eventually. Who cares if D-STAR takes up repeater pairs that could be used for analog? Have you listened to the analog repeaters? They're mostly silent anyway. One comment that I read early on (and I don't recall who said this) was that in an emergency the analog users would not be able to access a D-STAR repeater. Yep, but so what? Do you really mean to tell me that each local area is covered by just one analog repeater? It just sounds to me like typical human behavior: resistance to change. This is a regional thing. On the coasts, where people are packed in like sardines, pairs are scarce. 'Round these parts, it's not too hard to find one with a little patience. And you're right... repeater systems continue to become increasingly quiet in many areas. That's a bigger-picture problem of lack of interest in Amateur Radio. But we're not going to be able to fix that problem here in this discussion. There's a good friend of mine that was so ticked off at the institution of no-code hams. He calls them rif-raff. He operates almost exclusively on the CW sections of the HF bands to avoid the no-code folks. It's sad because there are a lot of no-code hams that are good operators and some are very technically knowledgeable. He might learn a thing or two from these folks. I was a no-code Tech, and I'm a low-code Extra. He can, as the cartoon character robot says... Bite my shiny metal ass. ;-) I'll take the riff-raff as a compliment, though. I wonder if the people in this group that are resisting D-STAR are missing the boat as well. Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog. Actually in today's day and age, missing out on D-STAR, P25, MotoTRBO and all the rest... would be a mistake. If our Charter is: §97.1 Basis and purpose. The rules and regulations in this Part are designed to provide an amateur radio service having a fundamental purpose as expressed in the following principles: (a) Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications. *(b) Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art. * *(c) Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communications and technical phases of the art. * *(d) Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronics experts. * (e) Continuation and extension of the amateur's unique ability to enhance international goodwill. We're way overloaded on people who take care of A E, and not so many who will work on B, C and D, in my not-so-humble opinion. The manufacturers and CODEC software writers are handling B. Hams are arguing all the time instead of learning about ALL of it, leading to a weakness in C. We have plenty of operators for D, but few technicians and electronics experts. This list being a very large notable exception. -- Nate Duehr, WY0X n...@natetech.com
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Old-fashioned? If you take being fashionable out of the argument, analog NBFM has some advantages which may not be appreciated until they're gone, particularly in emergency ops. Interoperability has been covered already, but there are some more subtle advantages to analog. If you have a station getting into the system only intermittently, is the operator being called away from the mic by local circumstances, or is he not making the repeater? Is it fading on the path, or a dying battery? Or, is something interfering with him on the input? How will you know? If it was analog, you could troubleshoot instantly, in your head, just by listening to the output. One of the problems facing LMR is the retirement of the last generation of techs who've ever heard picket-fencing. There is an intuitive understanding of issues such as multipath we all acquired using NBFM. Some of the new kids who've only played with digital have read about multipath, and maybe learned how to predict or measure it, but they'll have to look in a book to know how to fix it. Will they even think to try moving the car 3 inches to see if it works now? In emergencies, you may also miss out on information contributed by someone overhearing your conversation in some digital scenarios. There's also listenability. Given the choice between an analog NBFM system set up properly, and a D* repeater, I know which I'd rather have playing in my headphones for 8 hours at a Red Cross shelter. (Disclaimer: I also still prefer a good AM signal to SSB, and good vinyl audio recordings to 32K MP3s. ;^) 73, Paul, AE4KR - Original Message - From: John Szwarc To: Repeater-Builder@yahoogroups.com Sent: Monday, April 05, 2010 5:10 AM Subject: RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) ...Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog... --
[Repeater-Builder] Re: D-Star (Protocol and Repeaters)
--- In Repeater-Builder@yahoogroups.com, MCH m...@... wrote: Threaded... John wrote: Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. Your callsign or the destination callsign? It's the latter that needs to be interlaced (well, really the whole header should be interlaced). I am not where I can quickly look at it again, but as I recall it was the entire header. Without really digging it apart it seems that my GMSK modem was delivering a longish stream as a series of blocks with the entire header inserted ahead of each block, whether that is artificial (created by the modem) or the on-air stream, I can't say for certain, but it seems to be something that Icom provides in the radio, based on page 3 of this paper http://www.google.com/search?sourceid=chromeie=UTF-8q=d-star+uncovered (middle paragraph, Icom has made use It tells me that people: 1) Don't want to jump aboard the one-source format yet. There are other ways to get on the mode, rather than using the Icom solutions. Most of them are home brewed or a combination of kits. The format is open to anyone to implement. 2) Don't want to give up the interoperability of analog. Maximum interoperability would be CW, wouldn't it? (Oh, yeah, a lot of hams don't use CW anymore, time has moved on.) 3) Don't want to switch to digital for whatever reason. (else P25 would be the format of choice since it's a multi-vendor standard) Multi-vendor and expen$ive if you want new, current generation radios. D-STAR is cheap by comparison. (Great entrepreneurial opportunities here.) And how do I get this $150 D-STAR conversion for my repeater? This is the real issue and question. Once you have a well engineered repeater (FM), the conversion to D-STAR is relatively simple and cheap. First the repeater should be true FM (not PM). You need access to Discriminator, Modulator, and PTT (optionally COR). In many repeaters these are already brought out to an accessory connector, but can otherwise be located in the radios. You add a Node Adapter GMSK modem board. There are two main sources: 1) The Satoshi board. About US$117 (Assembled board - http://d-star.dyndns.org) there is some history here and he locks his boards to the owner's callsign (there is some bad blood between him and the next option). 2) The G7LTT/NI2O board (US based) US$80 as a kit, US$110 assembled - it runs both Satoshi firmware and PA4YBR firmware. PA4YBR is obtained for around US$15 at www.dutch-star.nl -- this is the board/firmware (PA4YBR) that I have. These boards have a DB-9 which is used for connection to the repeater and a USB port used for programming the board parameters and sending the datastream between the board and software on a computer to talk to the Internet. Alternatively, there is a sound card based GMSK modem, that uses a Vellman K8055, Serial port, or URI for PTT/COR by Jonathan Naylor, G4KLX. See http://groups.yahoo.com/group/pcrepeatercontroller -- BTW, this design includes a plan for a combined Analog/D-STAR repeater as some here think would be a good idea. Each of these adapters (or software) can run as a standalone repeater, or can communicate with the D-STAR network using additional gateway or hot spot software. There are a lot of options in this space. Mostly discussed on http://groups.yahoo.com/group/pcrepeatercontroller and http://groups.yahoo.com/group/gmsk_dv_node lists. There is also code, soon to be released, from a project by G4ULF, see http://g4ulf.blogspot.com/ Once you have your board (or G4KLX's soundcard software) it is time to mate it to the repeater. This involves connecting the respective Disc, Mod, PTT, and optionally COR lines to the board or soundcard. Next you will need to adjust the deviation on the repeater transmitter (about 1.9 khz. as I remember YMMV) and the audio levels in and out of the board or soundcard. Configure parameters; callsign, network connection (if used), and inversion/non-inversion of transmitted and received signals. That's pretty much it. I can tell you with certainty that having D-STAR (or most digital voice modes) on the same repeater with analog users is impractical in amateur radio. Many, if not most hams, don't even use CTCSS on their radio's squelch and even if they did the squelch can be falsed by the digital signal. We have a D-STAR repeater in the Seattle area (atop a 42 story building) and it is on a Shared Non-Protected pair on 2 meters. The sync pattern at the beginning of transmissions will open the squelch on CTCSS squelched radios (100 hz.) at 60+ miles away (for users of another FM only SNP
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Both GMSK modem and DMK URI provide a shaped and limited waveform that can be directly FM'ed at what is easily set to 1.8khz +/- typical... ( this is what the Icom stations use) the waveform is cleaner out of my station than the Icom D-Star radio keying it and filtering is better out of the station. Excessive deviation really annoys Icom's D-Star radios so not much slop is tolerated. Deviation above ~2k is a problem as the receiving radios start having issues. We have no currently mandated amateur initiative for 12k5 (11k0f3e) let alone 6k25 (6K00F3E/2D/2E) so I am not losing a lot of sleep with my 12k5/25k0 switchable receiver running in 25k0 mode...My repeater council authorized spectrum allocation is a 25k0 spec channel.. The GMSK modems and URI's do not seem to care as of now.. so I am planning on dealing with narrowband RX hardware down the road...Hardware narrowband filters are much more problematical in flatness and ringing... etc... What we really need is DSP based second IF's.. I suspect with HPSDR and other similar projects.. in the not too distant future...we could and will come up with an 11.2 mhz (or whatever is needed for a particular station... ) DSP based second IF with direct sampling hardware... just like, for one, GE ( Harris) does for P25.. I think it will come sooner than later. We are, after all, part 97.. not part 90 here.. My R D budget is a lot less than Icom or Motorola... but if we do not try... we never will get there...as has been said before..necessity is the mother of invention... In my state we authorize 25k0 modulation on 12k5 centers in non overlapping areas of operation... both use 16k0f3e deviation masks so I am not really worried about trying to set 6k25's adjacent TODAY... For now I think we are safe using 12k5 channel masks and channel centers for coordination ...and operate there on 6k25's and we will worry about getting closer as equipment gets better... As has been pointed out by others.. we have lots of non used repeaters.. In most of the US..we are not really in a spectrum crunch.. we are in a political crunch to figure out what constitutes underutilized and how to-be-recovered pairs can be returned for re-use. For the most part.. in amateur...6k25 is necessary only because it is the D-Star SPEC... not because we have that great of spectrum issues in most of the country..technology will catch up as need arises...and I do not think most places we are there yet. Doug KD8B Jeff DePolo wrote: Anyone who is currently building analog AllStar Link repeaters using a DMK URI already has the parts for a D-Star repeater .. assuming your TX and RX will handle GMSK data of your repeater.. This includes many Mastr II stations which seem to be a large portion of the amateur repeater world.. What are people doing about narrowbanding the RF hardware? There's no geo-spectral advantage to be gained by using D-Star/GMSK with a theoretical OBW of 6 kHz when the RF equipment is still wideband (mainly Rx IF, but also Tx must also be limited and LPF'ed). --- Jeff WN3A
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
hi all, May I ask the follow question. For a single site Voice communication digital repeater operation in identical conditions, which format /system type will work better in multi path signal ,with lager coverage area. FDMA,TDMA (D-Star ,Mototrbo,P25,Nexedge,Idas) ? TNX 73s de VR2XVD/W.L.Ho 6 Apr.10 On Tue, Apr 6, 2010 at 12:58 AM, MCH m...@nb.net wrote: There are P25 repeaters on the air. Granted, not as many as D-STAR (strictly talking about ham systems), but I know of nobody giving away P25 repeaters. Also, I bet there are more P25 receivers owned by hams than D-STAR since there are several scanners that decode P25, and only a few that decode D-STAR (not ironically, all made by Icom). Anyway, the point is not which format to use, but to make the systems as flexible as possible so they can be available in emergencies. Simply put, D-STAR is not as flexible as P25 since a P25 repeater can be made to pass P25 or analog. Granted, D-STAR does have some format benefits, but those could easily be added to P25 (or, the P25 benefits could be added to D-STAR, as has been discussed). There are also MotoTRBO repeaters in the ham bands, now. The more various formats you add to the mix, the less we will be likely to use them when they are needed. On the other hand, all the radios can use analog - making it the clear choice for emergency communications. Joe M. John Szwarc wrote: Okay. I've been reading with some interest the threads on D-STAR. There have been some very good points and some pretty amusing ones. P25 sounds interesting, but you will have to take note of the fact that it has not been widely accepted by the ham community. And considering that it (P25) is not compatible with D-STAR's AMBE codec, I doubt that it will be accepted by hams anytime soon. Who cares if D-STAR takes up repeater pairs that could be used for analog? Have you listened to the analog repeaters? They're mostly silent anyway. One comment that I read early on (and I don't recall who said this) was that in an emergency the analog users would not be able to access a D-STAR repeater. Yep, but so what? Do you really mean to tell me that each local area is covered by just one analog repeater? It just sounds to me like typical human behavior: resistance to change. There's a good friend of mine that was so ticked off at the institution of no-code hams. He calls them rif-raff. He operates almost exclusively on the CW sections of the HF bands to avoid the no-code folks. It's sad because there are a lot of no-code hams that are good operators and some are very technically knowledgeable. He might learn a thing or two from these folks. I wonder if the people in this group that are resisting D-STAR are missing the boat as well. Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog. Just my 2 cents. I'll go back to my corner now. John N3SPW -- *From:* Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com] *On Behalf Of *Nate Duehr *Sent:* Monday, April 05, 2010 4:01 AM *To:* Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com *Subject:* Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) On Apr 4, 2010, at 2:30 PM, John wrote: --- In Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder%2540yahoogroups.com, Nate Duehr n...@... wrote: I like D-STAR as a not-very-well-designed first try and use it... but it's seriously technologically flawed. Some of that can be fixed... other things like the header information not being interlaced... -- Nate Duehr, WY0X n...@... Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. I believe if you'll look again, the callsign of the sending station is interlaced, but not RPT1/RPT2, and the destination address, which are the essential routing information. Plus, you're correct: Judging by the behavior, the repeater's don't look at that data or utilize it anyway. -- Nate Duehr, WY0X n...@natetech.com nate%40natetech.com mailto:nate%40natetech.comnate%2540natetech.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.800 / Virus Database: 271.1.1/2791 - Release Date: 04/04/10 14:32:00
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
On Apr 5, 2010, at 7:01 PM, vr2 xvd wrote: hi all, May I ask the follow question. For a single site Voice communication digital repeater operation in identical conditions, which format /system type will work better in multi path signal ,with lager coverage area. FDMA,TDMA (D-Star ,Mototrbo,P25,Nexedge,Idas) ? TNX 73s de VR2XVD/W.L.Ho You will be spending a lot of time field testing to find out. There's no standard tests available for anything further than signal strength. It's rare to find necessary engineering data like at which Bit-Error Rate the CODECs fall apart, etc... to do proper engineering testing. GENERALLY: Multi-path: Digital falls apart sooner in multi-path conditions than analog does. Or should I say, before the DSP filter between your ears can't copy the analog signal. Larger coverage area: Has absolutely nothing to do with the protocol chosen, unless one were to prove that one or the other has a higher tolerance for BER. At the end of the day, nothing has rescinded the underlying physical RF principals, so a good antenna system, filtering, and pre-amplification if appropriate for the radio and the site -- will yield good results on all. All things being equal -- which they never are in the real world -- the protocol doesn't matter other than knowing at what BER the engineer chose to cut off the decoding and give up. So... there's no one or right answer to your question. All you'll get is anecdotes in response. Which are useful for the 10,000' overhead view of what's going on out there, but not nearly as useful as lab testing. Individual systems (like P25, because of its widespread adoption in professional circles, and D-STAR because a VERY limited few hams have set up excruciatingly tedious and painstaking tests to try to reverse-engineer some of these answers - THANKS Utah VHF FM group, by the way, from ALL of us!) will have some test data published, often in obscure places, but I know of no one lab that has tested all of these together, same workbench, same standards. It will also be VERY hard to get a field-test answer to this question unless you had all of the repeater types (so you could alternately plug one or the others into the EXACT same antenna/pre-amp/filtering system, and had calibrated all of the mobile rigs to EXACTLY the same power output and ran them around in the exact same car, on the exact same antenna... then drive all over the coverage area and come up with some objective way of measuring how does it sound. (In the wireline VoIP world, this would be done with the MOS score, for example. I've seen a FEW 2-way radio articles about how the CODEC was picked for P25 was done similarly, but there was no RF component involved in that system many years ago... just the choice of CODEC for intelligibility. Now they're starting to usE AMBE2, so obviously that tells us that, AMBE wasn't perfect...) If the engineering for the data side of things were available, better guesses could be made, with lots of assumptions... but good luck getting that data from the manufacturers. And you won't find any test gear capable of measuring all of the above systems that a) can do them all... but that will change... and b) doesn't cost more than a brand new foreign sports car. You've asked the question of a lifetime. Not because it's difficult, because it'll probably take about a lifetime for this all to shake out and someone to have the answer you're looking for. Your mileage may vary, -- Nate Duehr, WY0X n...@natetech.com
[Repeater-Builder] Re: D-Star (Protocol and Repeaters)
--- In Repeater-Builder@yahoogroups.com, Nate Duehr n...@... wrote: I like D-STAR as a not-very-well-designed first try and use it... but it's seriously technologically flawed. Some of that can be fixed... other things like the header information not being interlaced... -- Nate Duehr, WY0X n...@... Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. It seems to me, that almost everywhere I go (and I have traveled extensively), if all of the repeater pairs are coordinated, most of them have essentially zero traffic on them and sometimes one individual or organization holds many pairs covering essentially the same geography. Why not convert or replace some of those analog machines? Conversion runs less than $150 if you are going to run without Internet connectivity, add a computer and router to the price for Internet connectivity. I can tell you with certainty that having D-STAR (or most digital voice modes) on the same repeater with analog users is impractical in amateur radio. Many, if not most hams, don't even use CTCSS on their radio's squelch and even if they did the squelch can be falsed by the digital signal. We have a D-STAR repeater in the Seattle area (atop a 42 story building) and it is on a Shared Non-Protected pair on 2 meters. The sync pattern at the beginning of transmissions will open the squelch on CTCSS squelched radios (100 hz.) at 60+ miles away (for users of another FM only SNP repeater in Port Angeles). Listening to the structured noise of a GMSK digital signal on your analog radio is not an activity one would want to undertake for any extended period. 73 de K7VE NW7DR - experimental D-STAR access point simplex and duplex.
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Threaded... John wrote: Hmmm... I'm sitting here with my NQMHS Node Adapter (GMSK Modem) and watching the binary stream, in both Hex and Char, off of my IC-91AD, while transmitting for a few seconds. It seems the callsign information is repeated on a pretty continuous basis looking at the trace. I think it may just be a repeater/gateway control implementation issue. Your callsign or the destination callsign? It's the latter that needs to be interlaced (well, really the whole header should be interlaced). It seems to me, that almost everywhere I go (and I have traveled extensively), if all of the repeater pairs are coordinated, most of them have essentially zero traffic on them and sometimes one individual or organization holds many pairs covering essentially the same geography. Why not convert or replace some of those analog machines? Conversion runs less than $150 if you are going to run without Internet connectivity, add a computer and router to the price for Internet connectivity. It tells me that people: 1) Don't want to jump aboard the one-source format yet. 2) Don't want to give up the interoperability of analog. 3) Don't want to switch to digital for whatever reason. (else P25 would be the format of choice since it's a multi-vendor standard) And how do I get this $150 D-STAR conversion for my repeater? I can tell you with certainty that having D-STAR (or most digital voice modes) on the same repeater with analog users is impractical in amateur radio. Many, if not most hams, don't even use CTCSS on their radio's squelch and even if they did the squelch can be falsed by the digital signal. We have a D-STAR repeater in the Seattle area (atop a 42 story building) and it is on a Shared Non-Protected pair on 2 meters. The sync pattern at the beginning of transmissions will open the squelch on CTCSS squelched radios (100 hz.) at 60+ miles away (for users of another FM only SNP repeater in Port Angeles). Listening to the structured noise of a GMSK digital signal on your analog radio is not an activity one would want to undertake for any extended period. Just with 100.0 Hz CTCSS or with any CTCSS? If just the one, it sounds like an incompatibility like 131.8 and 136.5 is with CDCSS. And as for having both, that may be reason #4 people are waiting for. There is no reason why analog and digital cannot coexist. Granted, it requires use of CTCSS/CDCSS (perhaps with the exception of 100.0 Hz), but it will certainly promote the use of the D-STAR format if they had a transition path. Of course, there is also issue #5 - no reasonably priced radios for D-STAR. Remember we are talking about people who resist buying a $40 CTCSS encoder. Besides, analog is completely interoperable. D-STAR (or any digital format) is not. I don't think we should follow the same path that has led to communications problems in the commercial world - problems that we have to step in and solve when a disaster strikes. Joe M.
