DStar versus DMR - First Impressions
17/06/15 09:09
Well I like to experiment with new things in amateur radio. While I continue to voice my disappointment with the lack of a united digital standard in amateur radio, I have resigned myself to the belief that we are going to have multiple digital methods in use for sometime until the market, if ever, determines which digital method will win out....which of course may never happen in the foreseeable future.
Since the price of new DMR radios has come down quite a bit, mostly because of the cheap Chinese radios, I decided to order one. I did not actually place an order until we had a few DMR repeaters in the area. I mean why buy a radio without anyone to talk to?
I ordered a CS750 which is a Chinese built radio by Covalue and marketed by Connect Systems in California. Connect Systems is also the company trying to produce the CS7000 which promises to support both DStar and DMR. The reason I purchased this radio is because it is low cost and second, because Connect Systems will service it if there is an issue with it.
So here are the first impressions with a radio and digital method I have used in less than 24 hours.
First, I have been told that DMR adoption is exploding with repeaters and users. Not my experience. I was told by a current DMR user that the North American talk group was one of the busiest. Not many people answering calls and not a lot of activity. I had a few QSOs, but compared to DStar Reflector 30 (which is just a regional reflector), there is no comparison. I have not found any activity yet on the DMR Midwest talk group or any of the local talk groups. In other words, where is everyone?
Second, audio quality between DStar and DMR is about equal. I really do not hear any significant difference. I will give to DMR that it seems to recover faster than DStar which means you do not hear the "R2D2" sounds when DMR becomes marginal.
Third, programming DMR is laborious in my opinion compared to DStar. With the newest generation DStar radios, about the only thing you need to program is your call. All the current DStar repeaters are pre-programmed into the DStar radios and the newest DStar radios have a GPS which will locate the closest DStar repeater for you. No guessing when traveling. DMR does not seem to have the ability to have such a function. I do not see anywhere where you can store the GPS coordinates of the DMR repeater.
The software that came with the CS750 is not nearly as easy to use as the Icom DStar programs or even Chirp. When I tried to import repeaters and contacts into the CS750 software, instead of appending the new contacts and repeaters to the existing contacts and repeaters, it just overwrites what was already there. This means I have to really do the cut and pasting with Excel first before trying to do the import. Yikes, more work.
Fourth, DMR does not seem to have the ability to let users build their own repeaters like you can with DStar. So as I understand it, the cost of a DMR repeater is about $1,800 minimum. I am not sure if that includes the networking gear to allow it to connect to all these various talk groups. Yes, you can easily build your own DStar repeaters and some have done it for a few hundred bucks.
Fifth, as far as I can determine, I also do not see an ability to use an external program like D-RATS to send digital messages and data through the radios. Maybe that is coming. We'll see.
Sixth, there does not seem to be a way, or maybe any availability, to provide hotspots. This would allow someone who does not have a local repeater to still be able to access talk groups from home, car etc.
Finally the biggest issue is the use of a registration number instead of a callsign. So when a user is transmitting on DMR, you do not see his or her call, you see a number. We are hams, we have calls and we use our calls. Surprising that DMR could not be modified to use a call instead of these registration numbers. Now you can get the call to display instead of the registration number, but that requires you entering in the user call along with the registration number into the contacts list. It's all manual. With DStar the call is always displayed.
So in quick summary, while DMR is useable, it is not nearly as ham friendly as DStar. That's because DStar was created for hams, but hams. DMR was created by commercial interests for commercial users and we hams are trying to make it work for us.
I will continue to use both and report on my experiences and findings in the future.
Since the price of new DMR radios has come down quite a bit, mostly because of the cheap Chinese radios, I decided to order one. I did not actually place an order until we had a few DMR repeaters in the area. I mean why buy a radio without anyone to talk to?
I ordered a CS750 which is a Chinese built radio by Covalue and marketed by Connect Systems in California. Connect Systems is also the company trying to produce the CS7000 which promises to support both DStar and DMR. The reason I purchased this radio is because it is low cost and second, because Connect Systems will service it if there is an issue with it.
So here are the first impressions with a radio and digital method I have used in less than 24 hours.
First, I have been told that DMR adoption is exploding with repeaters and users. Not my experience. I was told by a current DMR user that the North American talk group was one of the busiest. Not many people answering calls and not a lot of activity. I had a few QSOs, but compared to DStar Reflector 30 (which is just a regional reflector), there is no comparison. I have not found any activity yet on the DMR Midwest talk group or any of the local talk groups. In other words, where is everyone?
Second, audio quality between DStar and DMR is about equal. I really do not hear any significant difference. I will give to DMR that it seems to recover faster than DStar which means you do not hear the "R2D2" sounds when DMR becomes marginal.
Third, programming DMR is laborious in my opinion compared to DStar. With the newest generation DStar radios, about the only thing you need to program is your call. All the current DStar repeaters are pre-programmed into the DStar radios and the newest DStar radios have a GPS which will locate the closest DStar repeater for you. No guessing when traveling. DMR does not seem to have the ability to have such a function. I do not see anywhere where you can store the GPS coordinates of the DMR repeater.
The software that came with the CS750 is not nearly as easy to use as the Icom DStar programs or even Chirp. When I tried to import repeaters and contacts into the CS750 software, instead of appending the new contacts and repeaters to the existing contacts and repeaters, it just overwrites what was already there. This means I have to really do the cut and pasting with Excel first before trying to do the import. Yikes, more work.
Fourth, DMR does not seem to have the ability to let users build their own repeaters like you can with DStar. So as I understand it, the cost of a DMR repeater is about $1,800 minimum. I am not sure if that includes the networking gear to allow it to connect to all these various talk groups. Yes, you can easily build your own DStar repeaters and some have done it for a few hundred bucks.
Fifth, as far as I can determine, I also do not see an ability to use an external program like D-RATS to send digital messages and data through the radios. Maybe that is coming. We'll see.
Sixth, there does not seem to be a way, or maybe any availability, to provide hotspots. This would allow someone who does not have a local repeater to still be able to access talk groups from home, car etc.
Finally the biggest issue is the use of a registration number instead of a callsign. So when a user is transmitting on DMR, you do not see his or her call, you see a number. We are hams, we have calls and we use our calls. Surprising that DMR could not be modified to use a call instead of these registration numbers. Now you can get the call to display instead of the registration number, but that requires you entering in the user call along with the registration number into the contacts list. It's all manual. With DStar the call is always displayed.
So in quick summary, while DMR is useable, it is not nearly as ham friendly as DStar. That's because DStar was created for hams, but hams. DMR was created by commercial interests for commercial users and we hams are trying to make it work for us.
I will continue to use both and report on my experiences and findings in the future.
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