Dstar Tutorial

Digital Smart Technology for Amateur Radio.

Developed jointly by Icom and the JARL (Japanese Amateur Radio League)

Currently, only Icom manufactures ready to use DStar radios but it is an open technology so there are several Amateurs working on interfaces to permit other brands to enjoy the technology.  There is also a device called a “DV Dongle” that attaches to a PC USB port and permits the owner to send and receive DStar transmissions to most Dstar repeaters and reflectors.  (More on reflectors later)   DV Dongles are available from Amateur Radio dealers such as HRO for around $200 US.  The software is free.

Update: January 2010. HRO is taking orders for the new DV-AP which is a dongle with a built-in low power 2 meter transceiver.  Expected to have the range of a typical “wireless mike” it allows the owner to plug it into a nearby computer, install the free software, and access the Dstar system using a Dstar enabled handheld such as the IC-91AD.  Input/Output frequency as selected; either any 2-meter simplex frequency or one of the digital frequencies below the repeater band.  Ship date unknown, 80 units were shipped and sold out the same day.  Backorders to be filled by the next production run.  Pricepoint: Around $250 usd.

Update: October 2010. Dplus v.2.2g has been released which changes some programming features.  These changes will be shown in italics where appropriate.

A typical DStar radio in it’s most basic configuration can send and receive analog signals on UHF and VHF.  It can be used in “simplex” mode meaning in a point-to-point configuration without the use of a repeater.  As with current analog radios, the range is limited to line of sight transmissions. It can also be configured, just as with an analog radio to work through a DStar repeater to communicate with other Dstar radios within range of that repeater.

In it’s most complex configuration, the DStar radio can simultaneously communicate with both the local repeater and at least one other repeater anywhere in the world.

Programming

All DStar radios have abundant memory to hold repeater frequencies and call signs.  While they all can be programmed by hand, it is much faster and easier to program them with a personal computer.  Software and interface cables are available from Icom as well as RTSystems.  Additionally there are Amateurs working on free software that will let you program your radio although all current offerings are fairly primitive.  Both Icom and RTsystems software http://rtsystemsinc.com/ work well and it is a matter of personal choice as to which is better.

The first thing to do is identify the repeaters you want to work and input the operating parameters such as the receive frequencies as well as the offset, both shift and direction of shift.  This information is available from the web at the following URL: http://www.dstarusers.org/repeaters.php You will notice that some repeaters have all three frequency bands available.  These are identified as the A band (1.2 gHz),  the B band (450 mHz) and the C band (145 to 148 mHz), while others have only one or two bands available.  W6CO for example only uses the UHF module so it is identified as W6CO B.

The next thing to do is program your call sign table with the appropriate call signs and other information.  In operation, you will find it extremely useful to associate alphanumeric  info with each repeater so you can figure out exactly where you will be operating.  More on that later.

The call sign table has four entries and each entry (the field) has eight data position.  It is very important to observe exactly where each character falls in each field.  The four fields are:

UR:
R1:
R2:
MY: N6XN

We’ll start from the bottom and move up since the last call sign (UR) gets many different configurations.

MY: This is where you input your assigned FCC call sign.  Most radios have space for several calls but unless you let others use your radio you need only to enter your own.  This field has room for eight characters, but you may notice there is a slash at the end of the call field where you can enter 4 more characters.  Some use this for their name, which works fine for John or Mark but you may notice at least one  ham goes by Stev.  There is a better place to put your name so the best thing to do is leave this blank or put in your radio type such as IC91 or 2820.

UR:
R1:
R2: W6CO   G
MY: N6XN

R2: This is where you enter the repeater call sign if you wish to use the system gateway which will put you into the world-wide DStar network.  The first seven spaces are reserved for the repeater call sign and the eighth space always(1) gets the letter G (for Gateway).  If you are setting up this memory for local use only, and don’t wish to be heard on the network, leave  R2: blank or set it to NOT USE.  Which ever you choose, this is where you would identify the channel so that the display shows you what you have programmed.  To input this you need to select MNAME (see your manual, on the IC91AD it’s on page 69).  On my radio, when I am on the channel that is programmed for local use only, no gateway, the display reads ” W6CO LOC” which tells me that on this memory channel there is no entry in the R2: field and I will only be heard on the local repeater, not on the DStar network.  The very next channel in my radio does have an entry in R2:  It looks like this:  W6CO   G and the alphanumeric readout says ” W6CO B G”  When I see this I know I will be heard both locally and on the DStar network when I transmit.

(1) An exception to using the G in the 8th position.  If you instead enter another module of the same repeater, you will cross band repeat on that repeater.  One would assume that the only reason you would do that is you had a radio that was only capable of a single band.  That being the case, the station you wished to communicate with would also want to cross band by doing the reverse.  Not a common practice.  Moving on:

UR:
R1: W6CO   B
R2: W6CO   G
MY: N6XN

R1: This is where you enter the call sign and module of the repeater you are using.  In Napa, for example, this would be W6CO   B (the B is in the last, or eighth position).  Normally, both R1 and R2 would reference the same repeater.  We’ll have some examples farther down the page.

UR: CQCQCQ
R1: W6CO   B
R2: W6CO   G
MY: N6XN

UR: Now we will get really complicated so pay attention.  For just communicating, the example above is how you would have your UR: set up; just CQ three times.  There are many other things that can go in this field however and most involve either control or linking.  If you have a control code in here, just press your push-to-talk until your control is accomplished then switch back to CQCQCQ to talk.  If you are performing repeater or call sign routing however, that is what goes in this field and you stay here while you talk.  More information on routing in a minute.

Control codes: This is a good place to talk about enhanced DStar.  In the beginning, the JARL version of the operating software only allowed routing, either to a repeater or to an individual using his call sign.  The problem was, you had no way of knowing if that individual was listening, or if the repeater he was on was in use.  You were really operating in the dark.  Then along came Robin Cutshaw, AA4RC and Dplus.  We are currently on revision v.2.2g and it has added complexity but many many more features than before.  It permits the operator to link or unlink other repeaters, or reflectors.  Once you have linked up you will hear any activity that is currently ongoing on that repeater or reflector and when you talk you will be heard on that repeater or reflector.  A reflector, by the way, is a Repeater-repeater.  In other words it is a specialized server that permits repeaters to connect to it and any traffic on that repeater will be automatically heard on any other repeater also connected to that reflector.  At this time there are 30 reflectors world-wide and at any given time there may be as many as 30 or more repeaters connected to any one of them.  Each reflector is set up with 3 partitions named A, B, and C (no relation to frequency) and the current convention is the C partition is used for rag chewing.  At this time, for example, W6CO  B is linked to REF014C, located in Las Vegas, and eight other repeaters are also on there.  Another four repeaters are linked to REF014A, and there are four dongles linked as well.  Any repeater linked to C can talk to any other repeater linked to C and to any of the dongles, but not to any of the repeaters linked to A.  The A’s talk to one another, the B’s talk to one another, and the C’s talk to one another.  The dongles can talk to anyone but they have to select which module they want.

Linking: Let’s say W6CO   B was not linked to anything and you wanted to link it up to REF014C.  Here is what your call sign table would look like:

UR: REF014CL
R1: W6CO   B
R2: W6CO   G
MY: N6RRR*

*I don’t know what your call is so I borrowed N6RRR.  Hope he doesn’t mind.  But put your own in here.

Notice the entry in the UR: field has eight characters and the last one is the letter “L”.  This stands for Link.  Now press your PTT for a second or two and release it.  You should hear a voice announcement saying “Remote Station Linked”, and if so you were successful.  Now switch your UR: to CQCQCQ and wait a few seconds.  From this point on, when you talk you will be repeated twice: once over the W6CO UHF DStar repeater, and almost simultaneously over every single repeater that is currently linked to REF014C. Kinda gives you the shivers doesn’t it?

Additional controls:

To unlink anything that is currently linked:

UR: U

Very important:  The control code always goes in the far right or eighth position.

To Interrogate to see if there is currently anything linked:

UR: W6CO   I

change by Dplus v.2.2g:  You only need the I in the 8th position.  A callsign is no longer required.

After pressing the PTT, you should hear one of two messages: “Remote System Linked” or just “W6CO” if unlinked.  In the next release of Dplus we expect we will be told exactly what is linked. And we do. With v.2.2g we now also see a scrolling message telling us to what we are linked.

To listen to yourself:

UR: W6CO   E

Leave it set like this while you send your test transmission

E (for echo) goes in the last position, the call sign of the repeater goes in the first for to six depending on the length of the call sign.  As with the I and U commands, E no longer requires a callsign.  Simply put an uppercase E in the 8th position. Why, you might ask, would one want to listen to himself?  Well, ego aside, the operator might wonder about the quality of the transmitted signal.  Some areas are spotty and your transmission can be garbled.  Some refer to garble as R2D2 named for the robotic character in the Star Wars movie.  Some will tell you that digital radio is wonderful; you either sound great or you don’t sound at all.  True enough, but there is an all-too-common third state called garbleland where part or all of your signal is just digital noise.  There are 3 main causes for this: Your signal is too weak,  you are experiencing multi-path distortion (very common where there are tall hills or buildings) or part of your header got clipped off.  The third condition happens when you get too quick on the trigger.  When you transmit, the very first thing that goes out is the header info.  This tells the controller what you have in your call sign table and it looks like this:

hdr f 400000 r2 K6MDD G r1 K6MDD A ur CQCQCQ my WA6YTD / fc d1a7 OK

This is a clip from the W6CO log showing a transmission by WA6YTD over the K6MDD A module. The hex code near the end is the transmission identifier and if part of that gets clipped the entire transmission will be unintelligible.  This is a good place to caution you about rushing your transmissions.  On any repeater it’s a good idea to pause  for a second or two or three before transmitting in case another station wants to break in.  In DStar it is doubly important for the same reason but also to let the internet swallow what you just fed it.

To link to another repeater:

UR: K6MDD CL

This would link the repeater you are on to K6MDD module C on Mount Diablo assuming that it is not currently linked to something else.  Any module can only be linked to one other module at any given time and chances are this would not work.  But if K6MDD C was not currently linked to something you could do this and you could then converse with anyone on the K6MDD C repeater as if you were right there.  Once again, as with the reflector example, you have to go back to CQCQCQ in order to talk, otherwise every time you keyed your mike the repeater controller would think you were trying to link and it would tell you so.  Courtesy:  If you link something, be sure to unlink when you are finished.

An important note on control codes: The controller stores call sign information temporarily because, in lieu of forward error correction, if something gets garbled it uses the last good data.  As a result, you can’t always switch things rapidly.  As an example, you might make a test transmission using the echo feature, then switch to CQCQCQ.  Often times your next transmission will also be echoed because the controller didn’t get the new UR: you sent.  Be prepared to wait up to a minute for the old data to be cleared.  Patience pays off.

Routing (as opposed to linking) Dplus aside, you can still do things the original way by putting another amateur’s call sign in the UR: field.  If he has transmitted on DStar anywhere in the world, the local repeater controller will try to find him and you will be heard on whatever repeater he last used.  This is a terrible way to try to communicate so it’s probably best to not use it unless you have an agreement with the party you want to talk to.  Also, keep in mind, if your local repeater is linked to a reflector, or if the distant Amateur’s local repeater is linked to a reflector, you may be creating a one-sided conversation for others.  Not that there is anything wrong with that…..or is there?  Poor practice.  Here’s a better way:

Repeater routing.  Let’s say you are in Tampa and want to talk to me in Napa.  Find the repeater info for Tampa http://www.dstarusers.org/repeaters.php and input it to your radio.  Then fill out your call sign table like this:

UR: /W6CO B
R1: KJ4ARB B
R2: KJ4ARB G
MY: N6RRR*

Don’t switch to CQCQCQ; leave it like this while you talk.  Anything you say will be repeated by W6CO…amaze your friends!

Here’s an important detail about this kind of routing.  If I am monitoring here in Napa, I will hear you call me from Tampa but you will be so clear that it will sound like you are right here in town.  I won’t be able to talk back to you unless I set my UR: to the repeater you are using.  Here is what my call sign table needs to look like in order to be heard by you:

There are a couple of ways I can do this but I need to know where you are calling from so your first call should sound like this:

“N6XN, this is N6RRR calling from Tampa through the KJ4ARB repeater port B”.  Repeat this a couple of times and then give me time to set my radio as shown below.  I can also call you back without knowing the repeater by pressing my “one-touch” button on the IC91,  (lower right of keypad)  See page 47 for more details.  All current DStar radios have a “one-touch” button somewhere.

These changes will be temporary.  If I move off frequency, when I dial back the call signs will have been restored to the original memory settings.

UR: /KJ4ARBB
R1: W6CO   B
R2: W6CO   G
MY: N6XN

Notice the UR: starts with a slash.  That tells the controller on KJ4ARB to find W6CO  B and pass any audio it hears to that repeater.  This works really well except for one peculiar condition:  Let’s say that W6CO  B is linked to REF014 and it just so happens that KJ4ARB B is also linked to REF014.  You would be creating a dual-route that probably would be a real train wreck.  At the very least you would be driving people nuts with the lost packets and garble.  There are ways to check before hand if something is linked (as I showed you above) or by using a PC connected to the web.  No PC handy?  Listen awhile or put out a general call and ask whoever answers.  If you hear nobody, (probably) just set it up like the above example and go for it.  No harm, no foul.  Another caution refers to interference with a QSO already in progress on the distant repeater.  If you set your UR: as in the examples above, and the remote repeater is in use, you will get a cryptic message on your display showing “rpt?”.  Wait a bit and try again.  If you set your UR: to link to a distant repeater, for example KJ4AR BL if that repeater is busy your link will still work but you won’t hear anything until the party that is currently talking finishes and releases his PTT.  You will then hear the next station to transmit and all those afterwards. Just to be on the safe side, after you complete a link, wait 2 or 3 minutes before talking. 3 minutes is max because DStar repeaters are equipped with 3 minute timeout timers that cannot be easily changed so that’s the max transmission time for most machines.

If you do have a PC handy, there are a number of “configurators” out there that will help you with programming.
Here is one that is popular: http://www.dstarinfo.com/Calculator/DSTAR%20Web%20Calculator.aspx?Source=WA6IRC

Here is a handy URL that will give you some examples of programming along with additional information on DStar: http://www.ladstar.org/config.htm

Here’s another URL  that will give you lots of information about how to look at reflector usage and other neat stuff:  http://w6dhs.org/ On this site you can find links to Dstarusers.org and find a list of reflector “dashboards”.  These can be really handy if you are near a PC but not much use if you operate mobile.

Dstar In Japan

US amateurs have only recently been able to communicate with Japanese hams via Dstar.  Seems ironic since the Radios, and the original mode architecture came from there.

The problem was, a key part of the Dstar system is the trust server.  In the US, the trust server is run by the K5TIT group in Texas.  Japanese hams have their own trust server and the two don’t talk.  What’s more, in the US, we have come to depend on Dplus programming on our gateways to let us communicate in the fashion described  in the body of this article.  In Japan, they don’t use Dplus, many are even unaware of it;  communications are carried out as described in your Icom manual.

That doesn’t mean we can’t talk to the JA folks though.  The first thing to be aware of is the time and date difference between there and here.  They are 7 hours earlier than us so if we are used to hamming on the way to work, most of Japan is fast asleep.  On our way home, and during our evening hours, they are at work.  It’s often best to wait until the weekend but be aware of the international date line;  they are on the other side of it so it is often “tomorrow” there.

In recent months, Japanese amateurs have been calling into the US by doing “repeater routing”  They will put a repeater callsign into the UR field preceded by a slash to look like this:

UR: /K6MDD B
R1: JP1YJX A
R2: JP1YJX G
MY: JI1BQW

If you are listening on some other repeater, such as W6CO  B we are probably all hearing K6MDD via a reflector.  All stations listening to the reflector on any repeater will hear the same thing.

A very important part of the JA’s transmission will be in the 20 character message that scrolls across your display.  Most US hams just put something simple in there like, John in Napa but the Japanese ham will put in something like this: “Please set your to /JP1YJXA”.  He will also ask you to do that during his call.  You may hear something like this:  “CQ Dstar Calling CQ from Northern Japan. Please set your reply to JP1YJX A. This is JI1BQW over.”

For more details see this link http://www.ji1bqw.com/how_to_call_japan_on_d-star_e.html

He will then stand by for several minutes to give you time to set your radio.  If you have the Japanese repeaters already set in your memory buffers this will only take a second.  Just dial in the new UR, select /JP1YJXA and reply to the calling station.  Speak slowly and distinctly and announce the repeater callsign and module you are calling through.  The Japanese ham will not need to change anything on his end because he knows, since you are calling him, that you are able to hear him.

Note: There are no 2-meter Dstar repeaters in Japan.  Their A-modules are all mostly 450 mHz and the B-modules are mostly 1.2 gHz.  I say “mostly” because the convention there is which ever module is first to be placed is A and the next module is B regardless of the band.  Usually though, it’s A=450 mHz and B=1.2 gHz. Having said that though, it does not matter to us unless we plan to visit Japan and operated from there.

Here is a partial list of the current Dstar repeaters in Japan.  If you input these callsigns, preceded by a slash, to your UR memory, you will be able to dial them up in seconds.

Callsign Location
/JP0YDPA Nagano
/JP1YEMA Kisarazu
/JP1YIQA Yokohama
/JP1YIUA Tokyo
/JP1YIWA Tokyo (west city)
/JP1YJOA Tokyo (Komae)
/JP1YJPA Maebashi
JP1YJQA Chiba
JP1YJRA Nagarayama
/JP2YGIA Nagoya
JP2YGKA Kasugai (City Hall)
/JP3YHHA Osaka
/JP3YHJA Osaka
/JP3YHLA Nara
/JP3YHCA Kyoto
/JP3VK A Hyogo
/JP4YDUA Hiroshima
/JP4YCOA Ehime
/JP5YCNA Kagawa
/JP5YCPA Kochi
/JP6YHLA Fukuoka
/JP6YHNA Kumamoto
/JP7YELA Myagi
/JP7YEMA Myagi
/JP8YDZA Hokkaido
/JP8YEAA Hokkaido
/JP9YEGA Ishikawa

These are only the earliest repeaters on line with Dstar.  An internet search will find you many many more.

Icom D-Star  DR Mode

January, 2010

Icom has superceded two of it’s popular Dstar radios.  The IC91AD handheld transceiver and the ID800 have been replaced by the IC80AD and the ID880H respectively.  While not a generational advance, these two radios incorporate a couple of important features that make them stand out.

The first advance is the programming software.  For the first time, Icom is providing the software free of charge.  The same software is used on both radios and for people familiar with the earlier versions, works very much the same.

The second feature, also an advance in programming is related to the something Icom calls the DR mode.  The manual is not much help in explaining this mode because of the differences between the way we use Dstar and the way it is used in Japan.  The folks at K6MDD, primarily Tim, K6BIV and Larry, WW6USA have pretty much led the way in the use of this mode.

What is DR mode and why should I use it?

If you use your radio in a fixed location such as a home station and only have one or two repeaters available to you, then the DR mode offers little advantage.  But if you travel out of your home area where other repeaters are likely to be encountered, then DR mode offers a huge advantage in the programming and in the operation of the radio.

Here’s why:

When D-Star was new, before Dplus, we programmed everything into our radios.  There were not many repeaters and we had lots of memory slots.  It was fairly easy to program the entire country into our radios even though we were not likely to ever travel that much.  But as more and more repeaters came on-line, the process became laborious and it was easy to fall behind.  Then Dplus came along and the programming efforts required grew exponentially because of the extra features.  Most radios ran out of memory slots.  Here is an example of the programming for just two repeaters, using D-Star G2, and Dplus:

The original way, before Dplus: (not all fields shown)

CH Frequency Dup Your Rpt-1 Rpt-2
0 444.1375 +DUP CQCQCQ K6MDD  B K6MDD  G
1 146.5800 +DUP CQCQCQ K6MDD  C K6MDD  G
2 440.6000 +DUP CQCQCQ W6DHS  B W6DHS  G
3 144.9600 -DUP CQCQCQ W6DHS  C W6DHS  G

The same two repeaters after Dplus:

CH Frequency Dup Your Rpt-1 Rpt-2
0 444.1375 +DUP CQCQCQ K6MDD  B K6MDD  G
1 444.1375 +DUP K6MDD  I K6MDD  B K6MDD  G
2 444.1375 +DUP K6MDD  E K6MDD  B K6MDD  G
3 444.1375 +DUP K6MDD  U K6MDD  B K6MDD  G
4 146.5800 +DUP CQCQCQ K6MDD  C K6MDD  G
5 146.5800 +DUP K6MDD  I K6MDD  C K6MDD  G
6 146.5800 +DUP K6MDD  E K6MDD  C K6MDD  G
7 146.5800 +DUP K6MDD  U K6MDD  C K6MDD  G
8 440.6000 +DUP CQCQCQ W6DHS  B W6DHS  G
9 440.6000 +DUP W6DHS  I W6DHS  B W6DHS  G
10 440.6000 +DUP W6DHS  E W6DHS  B W6DHS  G
11 440.6000 +DUP W6DHS  U W6DHS  B W6DHS  G
12 144.9600 -DUP CQCQCQ W6DHS  C W6DHS  G
13 144.9600 -DUP W6DHS  I W6DHS  C W6DHS  G
14 144.9600 -DUP W6DHS  E W6DHS  C W6DHS  G
15 144.9600 -DUP W6DHS  U W6DHS  C W6DHS  G

As you can see, Dplus changed only the “Your” field but because each line was a record, any change to any field changed the entire line.

DR Mode has returned  sanity to programming your radio.  We now have a 300 memory slots called “Repeater List”.  In this group of memories we can enter the repeater information in a briefer format (some features such as digital squelch not available) and the “Your” field can now be separated from the line and replaced by any UR call in the GRP UR memory.  The GRP UR memories are found in the programming software under “call sign” and contain 60 fields for all those Dplus functions.  In the DR mode, the user simply enters the repeater info such as frequency, offset, repeater callsign, repeater name, and checks “use as R1″.  Once DR Mode is enabled, by a single click of the <DR> button, the user selects GRP UR and selects the Dplus function required.  If anything other than CQCQCQ is selected, the R2 slot will be populated with the repeater callsign plus G for gateway.  If CQCQCQ is selected, the radio assumes you want to talk only on the local repeater and the R2 (gateway slot) is cleared.  The final step is to add a UR other than CQCQCQ and when you select that as your URcall, the R2 (gateway) slot remains populated.  Some ops are using DR CQ  or DR CQ CQ as a UR, but in reality almost anything works.  I have tried <VOICE>  <YAKYAK> and <RAGCHEW> with success.  In the end it does not really matter since the only person other than you who will ever see it is the system admin and he doesn’t care what you use.

The Dplus functions are also simplified by adding the needed control URs.  Unlinking can be accomplished by having a single <U> in the 8th position but it helps identify it to the operator by entering it as < UNLINK U >  just be sure the U is in the 8th position.

Once in DR mode you can jump from UR to UR very easily by just spinning the tuning knob.  Very nice when mobile!

It still makes sense to use the original programming method if you just use a few repeaters but for operators that move around, DR mode simplifies things immensely.

We’ll undoubtedly have updates to this page as the users discover other tricks with the 80 and 880 radios and as Icom brings out new Dstar models it is likely that they too will incorporated the DR mode.

If you are fortunate enough to be using an IC-91AD or IC-92AD, you will find the letters “CQ” on your keypad. (It’s on the Zero key).  By pressing this button and holding it, you can twirl your tuning knob and select any of the UR calls that are loaded into your memory table under Dstar/Settings/Your Callsign.  To return to your original memory setting just rock the tuning knob a click and then back.  This feature is very useful if you store CQCQCQ, U, I, and E in the first 4 slots.  Follow those with your favorite reflectors and you will be able to jump around with ease.

About n6xn

It all started in 1968 at a small 100 Watt radio station in Napa California. Looks like I finally got my priorities straight: the career is on the back burner and the K3 is getting some air time.
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