Thinking about going D-Star

[KJ4OHY]

I have been an amatuer radio operator for about a couple of years now, and I am looking to get a new mobile radio with D-Star. I just had a question, and perhaps an opinion of radios from users.

1: I have been researching the different call sign settings/fields in D-Star radios and was wondering if you were to put a specific user callsign into the your field, would it just be directed to that one user, or just an open transmission to the repeater that the user is on?

2: Looking at radios, I notice the 880h is D-Star ready, where as the 2820h is D-Star optional with the uc-123 being 200+ dollars. I like the layout of the 2820h better, but is it worth the extra $200 plus for the radio and another $200+ for the chip?

Thanks in advance!

 

[stevelton]

I can answer the question about the call sign routing.
By having the other persons call sign in the UR field, all that would do is route your transmission to the repeater where his callsign was last heard. Anyone on the repeater you are using, and the repeater that he was last heard on can hear your transmission, since amateur radio is not private, and you cannot prevent someone from hearing your transmissions.
The other person, however, can set his radio to only unmute for a transmission coming from you, if he enables call sign squelch. This way his radio stays quiet until someone is calling him specificlly.

Steven

 

[KJ4OHY]

Ok! Thanks for the information. Actually went to HRO yesterday picked up a few books on D-Star and looked at some radios. I think I will end up getting two of the 880h's since one 2820 with the digital chip costs the same amount as both of the 880h's. Hopefully this will finally get my wife interested in picking up the hobby with me.

 

[SCPD]

I think you should wait to see what Yaesu comes out with (I hear it is going to be MotoTrbo like), which will give you better audio than DStar and probably a cheaper price as well.

 

[N5TWB]

2: Looking at radios, I notice the 880h is D-Star ready, where as the 2820h is D-Star optional with the uc-123 being 200+ dollars. I like the layout of the 2820h better, but is it worth the extra $200 plus for the radio and another $200+ for the chip?

I have the predecessor to the 880h, the ID-800, and I'd say the only reason to go with the 2820 would be to get the dual-band receive capability. If that is not critical to your needs, then the 880 being D-Star ready out of the box will suffice.

 

[dedricw]

I think you should wait to see what Yaesu comes out with (I hear it is going to be MotoTrbo like), which will give you better audio than DStar and probably a cheaper price as well.

Why wait for yeasu? First of all they dont have a digital radio period.
They have an idea if that, there are no blue prints, no layout, nothing in the line being built, all they did was faked a leak pdf file to see how hams would respond and some ran with it.
If they did have any plans for digital for hams it left with motorola.
Yaesu does not have the R&D nore the funds to take a chance to see if hams will bite.
D-Star is here and it will be around for a wile. Its for hams by hams and not some hand me down like P25.

 

[KJ4OHY]

Just an update. Picked up two Icom 880h's today at the HRO in Woodbridge. So far I love them, the menu isn't set up all to complex. I did an FM audio check and the responce was that I sounded great, no lack of bass etc. Tried D-Star but nobody was on the repeater at the time. I am using the software to program them as I type this.

 

[KJ4OHY]

As I stated in my previous post, I have two icom 880h's. I have them both installed into mine and my wife's vehicles but noticed something strange. When I had them hooked up at home as a temporary base station before the install, I would key a D-Star repeater, the radio would display the ur callsign (CQCQCQ) and resume normal display. In my vehicles, most of the time when I key on the same repeater, it displays the ur callsign, back to normal display for a fraction of a second and then displays RPT?WS4VA C (or B depending on what port I am on). I noticed a youtube video where someone was transmitting onto a net and was heard no problem with the same RPT? message showing. Was wondering what this error was for and if it's common even if there's no problem communicating with the repeater. I am about 20-25 miles from the repeater depending on where I'm mobile, but have absolutely no problem hitting the FM repeaters operated by the same club. Does the digital mode decrease range? If so I wouldn't figure by that much. Unfortunately I haven't been able to make actual d-star contacts due to very little repeater activity. There is a net tomorrow, I'll try to get on it then. I have checked dstarusers and saw my call on the repeater log, while also having one of the radios listening on the repeater while I transmit on the other.

Sorry for the clutter of a story, but just trying to figure out what the RPT?XX4XX C is all about.

Thanks in advance!

 

[newsphotog]

As I stated in my previous post, I have two icom 880h's. I have them both installed into mine and my wife's vehicles but noticed something strange. When I had them hooked up at home as a temporary base station before the install, I would key a D-Star repeater, the radio would display the ur callsign (CQCQCQ) and resume normal display. In my vehicles, most of the time when I key on the same repeater, it displays the ur callsign, back to normal display for a fraction of a second and then displays RPT?WS4VA C (or B depending on what port I am on). I noticed a youtube video where someone was transmitting onto a net and was heard no problem with the same RPT? message showing. Was wondering what this error was for and if it's common even if there's no problem communicating with the repeater. I am about 20-25 miles from the repeater depending on where I'm mobile, but have absolutely no problem hitting the FM repeaters operated by the same club. Does the digital mode decrease range? If so I wouldn't figure by that much. Unfortunately I haven't been able to make actual d-star contacts due to very little repeater activity. There is a net tomorrow, I'll try to get on it then. I have checked dstarusers and saw my call on the repeater log, while also having one of the radios listening on the repeater while I transmit on the other.

Sorry for the clutter of a story, but just trying to figure out what the RPT?XX4XX C is all about.

Thanks in advance!

The "RPT?" message is normal. I get it all the time and it was explained to me by the D-STAR Yahoo mailing list that it sometime says that because you have CQCQCQ in the URCALL field... the radio will display an error-like message because there's no repeater or user with the callsign CQCQCQ. Nothing to worry about there.

Technically digital has the same "range" as analog, but the difference is the intelligibility. Digital will be more intelligible than analog due to error correction. The only caveat is that you get total clarity or nothing at all with digital... not much in between like there is static with analog.

 

[KJ4OHY]

Actually I was mistaken when I posted this. The error I am coming back with was UR?WS4VA C.

 

[travisd]

Actually I was mistaken when I posted this. The error I am coming back with was UR?WS4VA C.

Is WS4VA by any chance the Calls of the repeater you're contacting? Looking up WS4VA on QRZ those come back to the Stafford Amateur Radio Association which runs repeaters. "UR?" sounds like they're asking who you are - perhaps they're expecting to see your callsign instead of CQ? Never touched D-star, so just guessing here

 

[r00ty]

I think you should wait to see what Yaesu comes out with (I hear it is going to be MotoTrbo like), which will give you better audio than DStar and probably a cheaper price as well.

I can only see this turning into a beta/VHS or Bluray/HDDVD battle.

Personally I am holding out for a truly open standard (I'm actually looking at making a fully software implementation with the early version of codec2, just as a proof of concept). That way hobbyists can make their own, and ALL manufacturers can include the standard in their radios.

Leaving it up to the manufacturers to make the decisions is going to create expensive closed solutions like D-Star. I can't imagine Yaesu is going to make anything more open.

With regards to the higher voice quality. Higher voice quality, is likely to come with a higher bitrate, a higher bitrate voice codec needs more FEC bits to cover it to the same redundancy. Meaning the overall TX birate will be much higher. Unless they have come up with some amazing modulation method, this will hurt SNR, and thus BER on weaker signals, and thus the effective range at a given ERP level.

So, not sure where that will go in the long run. 2k AMBE is clear enough for comms use.

EDIT: Sorry for drifting off topic. As for the 880. I have one of these, they're quite nice for both mobile and shack use.

 

[JRayfield]

DMR (Digital Mobile Radio) is a "truly open standard".

John Rayfield, Jr. CETma

I can only see this turning into a beta/VHS or Bluray/HDDVD battle.

Personally I am holding out for a truly open standard (I'm actually looking at making a fully software implementation with the early version of codec2, just as a proof of concept). That way hobbyists can make their own, and ALL manufacturers can include the standard in their radios.

Leaving it up to the manufacturers to make the decisions is going to create expensive closed solutions like D-Star. I can't imagine Yaesu is going to make anything more open.

With regards to the higher voice quality. Higher voice quality, is likely to come with a higher bitrate, a higher bitrate voice codec needs more FEC bits to cover it to the same redundancy. Meaning the overall TX birate will be much higher. Unless they have come up with some amazing modulation method, this will hurt SNR, and thus BER on weaker signals, and thus the effective range at a given ERP level.

So, not sure where that will go in the long run. 2k AMBE is clear enough for comms use.

EDIT: Sorry for drifting off topic. As for the 880. I have one of these, they're quite nice for both mobile and shack use.

 

[r00ty]

DMR (Digital Mobile Radio) is a "truly open standard".

John Rayfield, Jr. CETma

Perhaps you misunderstood my meaning. I meant from beginning to end. The vocoder used in DMR is an AMBE, patented codec requiring a chip to use legally which cost money.

I think we need something that a can be run on a PC for close to zero cost (cost of packet cable and/or PTT adapter), hobby boards and various amateur derived designs in addition to commercial radios built to include it.

That's the point I'm making. There's also nothing wrong with using d-star (or even DMR), I myself have an ICOM D-star radio. But, for the hobbyists out there that like to tinker, there needs to be a truly free solution.

My other main point is ICOM and Yaesu slogging it out with differing standards using commercial chip only vocoder implementations isn't really in the spirit of the hobby.

 

[JRayfield]

If everything was free, then there would be no innovation. DMR would not exist, neither would D-Star or any other 'new' digital platform. And how far 'down' to you want to go? You refer to something that can run on a PC. But that PC uses microprocessors that someone built. Are you going to build your own microprocessor. I doubt it. And if everything was 'free', then there wouldn't be any microprocessors, either.

The vocoder from DVSI is quite inexpensive - only around $20 to $30 each, in single quantities, depending upon the exact 'model'. That's much less than most microprocessors for PC's. So what if it's patented and only available from one source? It's still very inexpensive, so why does it need to be 'free'? I'd much rather have DVSI making good money on their patented product line, while offering it at a very reasonable cost, and have the income to put back into research and development so that they can keep making better and better products for us to use. The AMBE+2 is MUCH better than the old IMBE vocoder, and if they hadn't made enough money on the IMBE vocoder, you can be assured that the AMBE+2 would never had seen the light of day.

John Rayfield, Jr. CETma

Perhaps you misunderstood my meaning. I meant from beginning to end. The vocoder used in DMR is an AMBE, patented codec requiring a chip to use legally which cost money.

I think we need something that a can be run on a PC for close to zero cost (cost of packet cable and/or PTT adapter), hobby boards and various amateur derived designs in addition to commercial radios built to include it.

That's the point I'm making. There's also nothing wrong with using d-star (or even DMR), I myself have an ICOM D-star radio. But, for the hobbyists out there that like to tinker, there needs to be a truly free solution.

My other main point is ICOM and Yaesu slogging it out with differing standards using commercial chip only vocoder implementations isn't really in the spirit of the hobby.

 

[r00ty]

If everything was free, then there would be no innovation. DMR would not exist, neither would D-Star or any other 'new' digital platform. And how far 'down' to you want to go? You refer to something that can run on a PC. But that PC uses microprocessors that someone built. Are you going to build your own microprocessor. I doubt it. And if everything was 'free', then there wouldn't be any microprocessors, either.

The vocoder from DVSI is quite inexpensive - only around $20 to $30 each, in single quantities, depending upon the exact 'model'. That's much less than most microprocessors for PC's. So what if it's patented and only available from one source? It's still very inexpensive, so why does it need to be 'free'? I'd much rather have DVSI making good money on their patented product line, while offering it at a very reasonable cost, and have the income to put back into research and development so that they can keep making better and better products for us to use. The AMBE+2 is MUCH better than the old IMBE vocoder, and if they hadn't made enough money on the IMBE vocoder, you can be assured that the AMBE+2 would never had seen the light of day.

John Rayfield, Jr. CETma

Oh, now wait a second. At what point did I say AMBE or commercial vocoders, codecs, or in fact anything were a bad thing.

What I said was (and I stand by it), that it was a bad thing for Amateur Radio. So many other digital modes are completely free to play with. Why should the de-facto digital voice mode for VHF need a commercial vocoder, especially now work is being done on an open version. Commercial radio makers working for commercial applications should be using commercial standards. Making radios for amateur radio use, I think it's in the wrong direction.

Now, I know D-Star is now quite established. But, I don't think the "next" mode (AKA Yaesu's alternative) should use yet another commercial vocoder. We have an alternative which can be developed and improved and used actively by the hobbyists.

Right now, you need to buy not just the AMBE-20x0 chip. But build electronics around it, to make it work. My proposition is that, most people wanting to use a digital mode have access to a computer. There's a nice new modular computer appearing on the market (Rasberry Pi) which is ripe for this kind of use. It's the right time to create a totally open source implementation.

As for the comment about computer microprocessors, any response to that would be just mudslinging in response to mudslinging.

 

[N1XDS]

As I stated in my previous post, I have two icom 880h's. I have them both installed into mine and my wife's vehicles but noticed something strange. When I had them hooked up at home as a temporary base station before the install, I would key a D-Star repeater, the radio would display the ur callsign (CQCQCQ) and resume normal display. In my vehicles, most of the time when I key on the same repeater, it displays the ur callsign, back to normal display for a fraction of a second and then displays RPT?WS4VA C (or B depending on what port I am on). I noticed a youtube video where someone was transmitting onto a net and was heard no problem with the same RPT? message showing. Was wondering what this error was for and if it's common even if there's no problem communicating with the repeater. I am about 20-25 miles from the repeater depending on where I'm mobile, but have absolutely no problem hitting the FM repeaters operated by the same club. Does the digital mode decrease range? If so I wouldn't figure by that much. Unfortunately I haven't been able to make actual d-star contacts due to very little repeater activity. There is a net tomorrow, I'll try to get on it then. I have checked dstarusers and saw my call on the repeater log, while also having one of the radios listening on the repeater while I transmit on the other.

Sorry for the clutter of a story, but just trying to figure out what the RPT?XX4XX C is all about.

Thanks in advance!

The "RPT?" message is normal. I get it all the time and it was explained to me by the D-STAR Yahoo mailing list that it sometime says that because you have CQCQCQ in the URCALL field... the radio will display an error-like message because there's no repeater or user with the callsign CQCQCQ. Nothing to worry about there.

Technically digital has the same "range" as analog, but the difference is the intelligibility. Digital will be more intelligible than analog due to error correction. The only caveat is that you get total clarity or nothing at all with digital... not much in between like there is static with analog.

What NewsPhotog already has said is right...When I'm operating on D-Star and look on the LCD screen on my 92AD handheld once the two beeps come and go I see the RPT notification scroll across the screen that means its responding to your voice going through the local D-Star repeater system/gateway.

 

[VK5ZEA]

Actually I was mistaken when I posted this. The error I am coming back with was UR?WS4VA C.

These cryptic messages that come back to you after keying up on an Icom G2 repeater... they are part of the Icom G2 software callsign routing system.

If you see "UR?" this means your callsign routed transmission was successful.

"RPT?" means that the destination repeater was not found.

A lot of confusion arises due to the different ways that a D-Star transmission can be sent via the internet. The original Icom G2 software only supportes callsign and gateway routing. This means you put another stations call in the "URCall" field in your D-Star radio and your transmission will be sent to the gateway/repeater where that station was last heard.

You can also send a transmission to a distant gateway and repeater by using a slash in the first character of the URCall field. eg URCall set to "/VK5REXB" will send your transmission to my local D-Star repeaters B module (70cm).

Virtually all gateway usage on D-Star needs the RPT1 and RPT2 callsign fields set correctly. RPT1 is the callsign and module of the repeater you are using eg for me it's "VK5REX B". RPT2 is the same but with a "G" in the eighth position eg. "VK5REX G". This is in addition to setting the frequency and offset correctly. There are some exceptions to the RPT1 and RPT2 requirement when using "personal" means of connecting to the internet, eg DVAP Dongle or GMSK HotSpot.

The Icom G2 software is "pushing" your transmission to a distant gateway/repeater. In the Icom G2 gateway world, there is no concept of linking... for a called station to get back to you they would need to set your callsign in their URCall field, this would send their transmission back to you. D-Star radios have a button to do this quickly.

The Dplus (and Dextra) add-on software allows a user to link to other gateways (and reflectors) and this permits easy two-way communications without the need to set specific callsigns in the URCall field. Generally "CQCQCQ " is set and the Dplus software sends the data stream off to where ever the gateway is linked to. This more analogous to how IRLP and Echolink works and also allows multiple stations on multiple repeaters to converse easily... something that is not easily done with callsign routing.

However, the Icom G2 software also sees this transmission and tries to send the call to a station called "CQCQCQ "... as this is an invalid callsign the Icom G2 software will respond with a "RPT?" message, It's telling you it can't route the call to 'CQCQCQ ".

Confusion sets in when you use callsign routing at the same time your gateway/repeater is linked to another gateway/repeater or reflector using Dplus. This makes your transmission head out on two paths.. one via Dplus and the other to the called station (as defined in URCall). If the called station "captures" your callsign and calls you back you will hear them fine... but Dplus will also then bounce this incoming call via the internet back out to wherever Dplus is linked to.

If someone at the other end of the Dplus link hears this call and tries to reply BUT doesn't know it was callsign routed to another station... then their reply using "CQCQCQ " will not make it back to the calling station... terribly confusing.

When I transmit a callsign routed call... I try to ensure my local repeater is unlinked... and I also state in my transmission that I am using callsign routing and that the replying station needs to "capture" my call using the RX>CS button in order to talk back to me.

Dplus is a more common way of talking on D-Star... but a knowledge of how the Icom G2 software works and how callsing routing works is very important too.

As briefly mentioned before there is another D-Star linking protocol called Dextra, this is an open source system that works similar to Dplus. There is a newer linking protocol emerging from Germany called X-Link that allows more robust sending of D-Star transmissions via the internet.

Dplus reflectors use 'callsigns' "REF001 C", "REF012 C", with up to five "modules" per reflector (A,B,C,D &E).
Dextra reflectors use "XRF005 A", "XRF021 B"... also with five "modules"
X-Net reflectors use "DCS001 x" etc. with the entire 26 alpha characters available in the 'x position'.

Probably a lot more info than anyone asked for... but I got typing and couldn't stop!

Michael.
VK5ZEA

 

[xmo]

Thanks for taking the time to post this excellent tutorial!

 

[pianotech]

As a new ham (got my ticket 3 weeks ago), I'm following this thread with interest, and have a few questions about D-STAR. It does seem that it's growing in popularity exponentially, and my questions are:

1. Why is it becoming so popular given the fact that it uses a proprietary codec and requires a specific brand rig?

and

2. Echolink does not require specific hardware (Icom), is open, and can be run the same way (accessing enabled repeaters), so what would be the reason to choose D-STAR over Echolink?

For instance, I have a Yaesu FT-250R monoband VHF HT right now. All I need to be is in range of an Echolink repeater, and I can connect to other linked repeaters globally with my existing rig.

Can someone shed some light?

73!

--Loren