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D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol specification developed as the result of research by the Japan Amateur Radio League to investigate digital technologies for amateur radio. While there are other digital on-air technologies being used by amateurs that have come from other services, D-Star is one of the first on-air standards to be widely deployed and sold by a major radio manufacturer that is designed specifically for amateur service use.

D-Star compatible radios are available on VHF and UHF and microwave amateur radio bands. In addition to the over-the-air protocol, D-Star also provides specifications for network connectivity, enabling D-Star radios to be connected to the Internet or other networks and provisions for routing data streams of voice or packet data via amateur radio callsigns.

The first manufacturer to offer D-Star compatible radios is Icom. As of December 30, 2008, no other amateur radio equipment manufacturer has chosen to include D-Star technology in their radios. Kenwood re-brands an Icom radio and distributes it in Japan only.

History

1999 – Funded by the Japanese government and administrated by the JARL, investigation was put into finding a new way of bringing digital technology to amateur radio.

2001 – D-Star is published as the result of the research.

Unknown Date – Icom enters the construction of the new digital technology by offering the hardware necessary to create this technology.

September 10, 2003 - Icom names Matt Yellen, KB7TSE, to lead its US D-Star development program.

December 2, 2003 - First Echolink over D-Star QSO is made between Matt Yellen, KB7TSE in Bellevue, WA, and Sheldon Kane, KE8VO of Urbana, OH

April 2004 - Icom IC-2200H is released. This is a 2-meter mobile, and the first "D-Star Optional" radio to be released commercially. However, a yet to be released D-Star add-on card is required for this radio to operate in D-Star mode.

November 2004 - JARL releases significant changes to the existing D-Star standard. Icom, aware that the changes were coming, had placed the release of their hardware on hold for a period of as much as a year while they awaited the changes. Now that the changes are out, Icom announces they will be able to finish up and release equipment

December 29, 2004 - The Icom UT-118 is shipping this week This is the add-on card that once installed to "D-Star Optional" radios, will provide D-Star connectivity. With this card added to the IC-2200H, the market now has its first D-Star radio!

December 2004 - The Icom ID-1 1.2GHz mobile radio is released. This was to have been the first D-Star radio, providing full DD functionality. However, it's release was delayed from it's original date of September 2003.

February 28, 2005 - Icom ID-800 is announced with an expected release date of 28 February 2005 This is the first dual-band 2-meter/70-centimeter mobile radio that is "D-Star Optional". It will use the optional UT-118 add-on card to provide D-Star digital voice.

April 2005 - People are reviewing their Icom IC-V82 2-meter handheld transceiver on EHam.net . The June 2005 edition of the ARRL's QST magazine also reviews the Icom IC-V82. They also mention the IC-U82, which is the 70-centimeter version of this HT. These rigs require the purchase and installation of the UT-118 add-on card to make them D-Star functional. These are the first commercial D-Star handhelds.

July 1, 2007 - First D-Star over satellite QSO occurs between Michael, N3UC, FM-18 in Haymarket VA and Robin, AA4RC, EM-73 in Atlanta GA while working AO-27.

February 1, 2008 - Icom announces the availability of Gateway 2.0 software.

April 23, 2008 - Icom and US trust server administration announce the shutdown of the Gateway 1.0 U.S. trust server will occur at 00:00 UTC on June 1, 2008, at which time all systems should have transitioned to Gateway 2.0 software and the new U.S. trust server.

November 22, 2009 - It's been about five years since D-Star made it to market with products for people to buy. As of the time of this writing, there are now around 10,800 D-Star users talking through D-Star repeaters which have connectivity to the Internet via the G2 Gateway. There are around 550 G2 enabled repeaters now active. . Note, these numbers do not include the scores of users with D-Star capabilities but not within range of a repeater, or working through D-Star repeaters that do not have Internet connectivity.

October 2010 - The first D-Star capable satellite Oufti-1 is scheduled for launch.

Technical details

D-STAR transfers both voice and data via digital encoding over the 2 m (VHF), 70 cm (UHF), and 23 cm (1.2 GHz) amateur radio bands. There is also an interlinking radio system for creating links between systems in a local area on 10 GHz.

Within the D-Star Digital Voice protocol standards (DV), voice audio is encoded as a 3600 bit/s data stream using proprietary AMBE encoding, with 1200 bit/s FEC, leaving 1200 bit/s for an additional data "path" between radios utilizing DV mode. On air bit rates for DV mode are 4800 bit/s over the 2 m, 70 cm and 23 cm bands.

In addition to DV mode, a high speed Digital Data (DD) mode can be sent at 128 kbit/s only on the 23 cm band. A higher-rate proprietary data protocol, currently believed to be much like ATM, is used in the 10 GHz "link" radios for site-to-site links.

Radios providing DV data service within the low-speed voice protocol variant typically use an RS-232 or USB connection for low speed data (1200 bit/s), while the Icom ID-1 23 cm band radio offers a standard Ethernet connection for high speed (128 kbit/s) connections, to allow easy interfacing with computer equipment.

Importance of Digital Technology and D-STAR

As long as the signal strength is above a minimum threshold, and no multi-path is occurring, the quality of the data received is better than an analog signal at the same strength.

The system today is capable of linking repeaters together locally and through the Internet utilizing callsigns for routing of traffic. Servers are linked via TCP/IP utilizing proprietary "gateway" software, available from Icom. This allows amateur radio operators to talk to any other amateur participating in a particular gateway "trust" environment. The current master gateway in the United States is operated by the K5TIT group in Texas, who were the first to install a D-Star repeater system in the U.S.

Another important aspect of D-STAR technology is its ability to send large quantities of data to emergency responders in the event of a disaster. Served agencies can instantly relate to sending "email" or "word files" to someone. The data sent can be high-volume, where traditional amateur radio "modes" are capable of getting a message through albeit slowly, D-STAR can place documents into the hands of those that need them most—fast image, text and document data exchanges.

Criticism

As is usually the case with any new technology, there will be critics. Just as there were people that showed disdain when SSB was introduced, referring to it as "Duck Talk", there are people that express borderline fanatical hatred for D-Star. The problem is compounded by the fact that since D-Star started in Japan, original historical information is hard to come by when you can't speak or read the language of the source. What's worse are the mistranslations, rumors, and assumptions that come with a new technology as people look to justify either for or against the new technology. So let's quickly address some of the complaints and criticisms.

Criticism 1 - "D-Star uses a proprietary CODEC." True... However, the question should be asked, "What was the alternative at the time the standard was developed?" The talk of using an open source codec over a proprietary one is a valid one. However, at the time the standard was developed, what was available? Was waiting for an open source CODEC feasible? How long has the amateur radio community waited for someone to step up and develop a codec that would become widely accepted and utilized? A good argument could be made that if the JARL had decided to wait for an open source CODEC, the Amateur Radio community would still be waiting, and Amateur Radio in Japan would have missed a golden opportunity to prove its viability to the Japanese government.

For a decent primer into the thought processes that must have gone on in the development of this standard, Here's a report of the ARRL's Digital Voice Working Group as provided to the Technology Task Force in January 2003. . Please note, the reference is not related to the JARL's development of D-Star. Rather, it is a different group discussing much of the same things the JARL must have when they were creating the D-Star standard. It provides some insight into thought processes and comparisons of various voice digitizing technologies that were available at the time.

It should be noted that a standard is just that. It is a document establishing guidelines anyone interested in joining in must follow. Standards are meant to be reviewed, changed, and modified over time. Now that the baseline has been established, the Amateur Radio community should be excited and thinking about where to go next with this new standard, and get involved in its revisions. If the proprietary CODEC is currently the Achilles heel of D-Star, then those involved in future development of the standard should recognize this, and make adjustments to the standard accordingly.

Bruce Perens, K6BP, amateur radio and open source advocate, has announced that he will investigate the development of an alternative codec.

Criticism 2 - "Icom owns D-Star." This is not true. Icom, by virtue of being first to market, has incorrectly been given this title by many. This is akin to stating Kenwood owns APRS since they were the first major manufacturer to build equipment to support that standard. D-Star is an open standard. The AMBE-2020 voice codec is the only proprietary element within the standard, and it is owned by DVSI, not Icom. Anyone can go to DVSI and purchase their own AMBE-2020 chip for about $20USD . Interested individuals will find many open projects being conducted within the D-Star community proving the standard is open, and Icom can't squelch the tinkering of the Amateur Radio community.

Criticism 3 - "It's too expensive." True, today it is. ...but remember $8000USD VCRs, $15000USD Digital Televisions? What happened? As of the time of this writing, it is easy to say 11,000+ D-Star enabled radios have been sold in the course of about five years, sales which can easily be considered as sold during the "early adopter" phase of the technology. Other manufacturers have to be looking at these numbers and making business decisions as to whether or not they should get into the market. ...and as is the case with any product, the more that are made, and the more options that are available, the cheaper the price will become.

Criticism 4 - "D-Star doesn't have the range of FM." If your definition of range is being able to break squelch on an FM repeater, then you are correct, D-Star doesn't have the range. However, if your definition of range refers to the ability to easily carry conversation at a comfortable level above background noise, then D-Star suddenly becomes very comparable to FM. While the quality of FM degrades in a linear fashion the further you move away from the source, D-Star maintains a constant and guaranteed "armchair" voice quality up to a point, then essentially "falls off a cliff". A good document comparing D-Star to FM can be found in this PDF document. Digital Voice versus Analog FM Sensitivity.pdf

Another thing to consider is power output. Whether it's FM or D-Star, the power output of the transmitter will affect the overall range of the system. Currently, all commercial D-Star repeaters in the 2-meter and 70-centimeter bands sold by Icom transmit at about 25-watts. When compared to most FM repeaters, this is a fraction, and as such affects the total range of the system.

The world's first non-Icom D-Star repeater

The world's first non-Icom D-Star repeater GB7MH, fully linked to the K5TIT G2 network and D-Plus, went live on 10 September 2009, in West Sussex, England. Whilst waiting for the DSL line installation, the repeater is connected to the Internet via a 3G dongle from network operator "Three". The system is built around Satoshi Yasuda's GMSK Node Adapter, a Mini-ITX system running CentOS 4, a Tait T800 repeater and G2 code written by G4ULF. All the usual G2 features such as callsign routing, D-Plus linkage and DPRS via D-Star Monitor are supported.

Source:- RSGB UK repeater website, www.ukrepeater.net

Gateway server

The current gateway control software rs-rp2c version 2.0, more commonly called "Gateway 2.0", runs on virtually any Linux, but the Icom-supported and -recommended configuration is CentOS 5.1 on a Pentium IV 2.4 GHz or faster machine.

The recommended configuration uses Linux CentOS 5.1 with the latest updates, typically running (kernel 2.4.20. glibc 2.3.2 and BIND 9.2.1 or later). The CPU should be 2.4 GHz or faster and the memory should at least be 512 MB or greater. There should be two network interface cards and at least 10 GB free of hard drive space which includes the OS install. Finally for middleware, Apache 2.0.59, Tomcat 5.5.20, mod_jk2 2.0.4, OpenSSL 0.9.8d, J2SE 5.0 and postgreSQL 8.2.3 are utilized, but these can be different as updates occur.

Along with the open-source tools, the Icom proprietary dsipsvd or "D-Star IP Service Daemon" and a variety of crontab entries utilize a mixture of the local PostgreSQL and BIND servers to look up callsigns and "pcname" fields (stored in BIND) which are mapped to individual 10.x.x.x internal-only addresses for routing of both voice and data traffic between participating gateways.

During installation, the Gateway 2.0 software installation script builds most of the Web-based open-source tools from source for standardization purposes, while utilizing some of the packages of the host Linux OS, thus making CentOS 5.1 the common way to deploy a system, to keep incompatibilities from occurring in both package versions and configuration.

Additionally, gateways operating on the U.S. trust server are asked during initial setup to install DStarMonitor which is an add-on tool that allows the overall system administrators to see the status of each Gateway's local clock and other processes and PIDs needed for normal system operation, and also sends traffic and other data to servers operated under the domain name of "dstarusers.org". Installation of this software also includes JavaAPRSd, a Java-based APRS interface which is utilized on Gateway 2.0 systems to interface between the Icom/D-Star GPS tracking system called DPRS to the more widely known and utilized amateur radio APRS system.

How Gateway 2.0 works

Each participating amateur station wanting to use repeaters/gateways attached to a particular trust server domain must "register" with a gateway as their "home" system, which also populates their information into the trust server a specialized central gateway system—which allows for lookups across a particular trust server domain. Only one "registration" per trust domain is required. Each amateur is set aside eight 10.x.x.x internal IP addresses for use with their callsign or radios, and various naming conventions are available to utilize these addresses if needed for specialized callsign routing. Most amateurs will need only a handful of these "registered" IP addresses, because the system maps these to callsigns, and the callsign can be entered into multiple radios.

The gateway machine controls two NICs, the "external" one being on a real 10.x.x.x network behind a router. A router that can NAT a single public IP address (can be static or dynamic in Gateway 2.0 systems) to a full 10.x.x.x/8 network is required. From there, the Gateway has another NIC connected directly to the D-Star repeater controller via 10BaseT and the typical configuration is a 172.16.x.x (/24) pair of addresses between the gateway and the controller.

Differences between Gateway 2.0 and Gateway 1.0

The main differences between Gateway 1.0 and 2.0 are the addition of a relational database (PostgreSQL) for more flexibility and control of updates, versus the previous use of only BIND for "database" activities, the addition of both an administrative and end-user Web interface for registration which was previously handled via command-line commands by the Gateway 1.0 system administrators, dropping the requirement for static public IP addresses for gateways, and the ability of the software to use a DNS FQDN to find and communicate with the trust server, allowing for redundancy/failover options for the trust server administrators. Finally, a feature called "multicast" has been added for administrators to be able to provide users with a special "name" they can route calls to which will send their transmissions to up to ten other D-Star repeaters at the same time. With cooperation between administrators a "multicast group" can be created for multiple repeater networks or other events.

Another additional feature of Gateway 2.0 is the ability to use callsign "suffixes" appended to the user's callsign in a similar fashion to the repeaters and gateways in the original system, which allow for direct routing to a particular user's radio or between two user radios with the same base callsign, by utilizing the 8th most significant field of the callsign and adding a letter to that location, both in the gateway registration process on the Web interface, and in the radios themselves.

Gateway 1.0 control software

The Gateway 1.0 software was similar to Gateway 2.0, and utilized Fedora Core 2+ or Red Hat Linux 9+ OS on a Pentium-grade 2.4 GHz or faster machine and Icom has announced a shut-down date for the U.S. Gateway 1.0 Trust Server, see "History" section.

Add-on software

Various projects exist for gateway administrators to add "add-on" software to their gateways, including the most popular package called "dplus" created by Robin Cutshaw AA4RC. A large number of Gateway 2.0 systems are offering services added by this software package to their end-users, and users are getting used to having these features. Features include the ability to link systems directly, "voice mail" (a single inbox today), ability to play/record audio to and from the repeaters connected to the Gateway and the most important, the ability for DV-Dongle users to communicate from the Internet to the radio users on the repeaters.

There is often a misconception by users and system administrators alike that the Gateway 2.0 systems have these add-on features from dplus by default, a testament to the popularity of this add-on software. Software development on dplus is very active right now, and features such as multiple repeater/system connections similar to the type of linking done by other popular repeater-linking systems (IRLP and EchoLink) are being worked on.

D-STAR Reference and Operating Guide

Many interested amateur radio operators have found it difficult to obtain information that clearly describes the various D-STAR operating modes and how to program their radios to make use of these modes of operation. A new book by Nifty Ham Accessories, the "Nifty E-Z Guide to D-STAR Operation" describes the many D-STAR Gateway 2.0 and Dplus operating modes, and popular Internet resources that are core to D-STAR communications.

After describing how D-STAR repeater systems are configured and inter-communicate via the Internet, the nut-and-bolts of how to program D-STAR transceivers is covered in detail. The book provides instructions for programming radios to take advantage of call routing and linking within the local repeater system and through Internet gateways to anywhere in the world.

Additional chapters are devoted to DV Short Messaging, and the d*Chat and D-RATS programs used for DV Mode slow-speed data communications. Finally a chapter is devoted to installing, configuring and using the popular DV-Dongle which uses a PC to access the Internet for D-STAR communications without a radio or local D-STAR repeater.

An introductory video was produced in 2008 by Amateur Radio Video News. Titled Digital Voice for Amateur Radio, the video covers new digital voice modes on HF and VHF/UHF, including an extended segment on D-STAR voice and data. The ARVN web site also has free YouTube hosted videos showing how to program D-STAR radios.

Manufacturers of D-STAR equipment

Equipment

• Icom D-STAR equipment
Transceivers:
• Icom ID-1: 23 cm digital voice and digital data mobile transceiver. Power is selectable at 1 W or 10 W. USB control port and Ethernet connection for data.
• Icom IC-2820H/IC-E2820: 2 m / 70 cm twin band digital voice mobile transceiver. Power up to 50 W on each band. May be purchased with or without D-STAR module. The D-STAR module includes a built-in GPS receiver with accompanying antenna.
• Icom ID-800H: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 55 W on 2 m and 50 W on 70 cm.
• Icom IC-92AD: 2 m / 70 cm twin band digital voice hand held transceiver. Four power settings up to 5 W on each band. Rugged and submersible design, optional microphone with embedded GPS.
• Icom IC-91AD/IC-E91 + D-STAR: 2 m / 70 cm twin band digital voice hand held transceiver. Power is selectable at 0.5 W or 5 W on each band.
• Icom IC-2200H: 2 m single band digital voice mobile transceiver. Power up to 65 W. Must purchase optional D-STAR module.
• Icom IC-V82: 2 m single band digital voice hand held transceiver. Power up to 7 W. Must purchase optional D-STAR module.
• Icom IC-U82: 70 cm single band digital voice hand held transceiver. Power up to 5 W. Must purchase optional D-STAR module.

Note: All mobile (including hand-held) radios may also be used on conventional analog FM.
Repeater equipment:

• Icom ID-RP2000V: 2 m digital voice repeater.
• Icom ID-RP4000V: 70 cm digital voice repeater.
• Icom ID-RP2V: 23 cm digital voice repeater.
• Icom ID-RP2D: 23 cm digital data access point.
• Icom ID-RP2C: Repeater controller. Can support up to four digital voice repeaters and digital data access points. Required to operate any Icom D-STAR digital voice repeater or digital data access point.

• Kenwood D-STAR equipment
Transceivers:
• Kenwood TMW-706S: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 50 W.
• Kenwood TMW-706: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 20 W.

Note: These transceivers are not available in North America and appear to be OEM versions of the Icom ID-800H

• Inet Labs
Computer accessory:
• DV-Dongle: USB device with AMBE codec, which can be used to generate D-STAR packets over the Internet through applications such as DVTOOL.
Note: Now available from a number of Amateur Radio dealers or by homebrew using documentation at Moetronix.

Compatible programs and online projects

D-StarLet

A Web-based text messaging application using D-Star digital data technology

D-StarLet is an open source client-server solution that allows content creation and modification from certain persons. D-StarLet interfaces with a D-Star radio through the serial port. It works with Windows (98+), Linux (Red Hat 7.3+), Apple Mac OS X, and others.

D-PRS interface

D-PRS is GPS for ham radio. Includes DStarTNC2, javAPRSSrvr, DStarInterface, and TNC-X

DStarMonitor

A Java application run on the repeater gateway PC which logs activity on the attached repeaters. Additional features include APRS object representation of each repeater.

DStarQuery

DStarQuery monitors the low-speed data stream of a D-STAR radio looking queries sent from a remote station. When a valid query is received, a predefined sequence is executed and the results transmitted from the station running DStarQuery. For example, a station transmits "?D*rptrs?" and it is received by a DStarQuery station which responds with a list of local repeaters.

The program D-PRS Interface includes a "Query" entry field that streamlines this process allowing the user to simply enter the desired command. Most DStarQuery systems will respond with a list of available commands when "?D*info?" is received.

d*Chat

A simple "instant message" or keyboard-to-keyboard chat application for DV mode. http://nj6n.com/dstar/dstar_chat.html

D-TERM

A simple "instant message" or keyboard-to-keyboard chat application for DV mode. http://www.d-term.de

D-RATS

An emerging D-STAR communications tool that supports text chat, email, TCP/IP forwarding, file transfers, and more. Written in Python to be cross-platform. Runs on Windows, Mac OS X, and Linux. A reflector devoted solely to relaying D-RATS communication is called a "Ratflector"

Dstar Comms PRO

An advanced software application for use with DStar enabled radios. Supports advanced text chat, personal messaging with auto-reply and inbox, e-mail gateway and a beacon mode. GPS Tracking / Logging and a GPS Beacon emulator and Internet linking. New features are added weekly and users can suggest new features through the Dstar Comms forum. www.dstarcomms.com

DSTARSWITCH

An open source project (under the GNU Lesser General Public License) geared towards allowing multiple applications to communicate through one D-STAR radio at the same time. Anyone may contribute to this project and will receive credit for doing so. DSTAR SWITCH is an open collaborated project for creating base libraries and applications to allow the passing of information from the host computer to the D-STAR radio and vice versa.

DStar TV

Slow Scan TV for DStar radios and video streaming for Icom ID-1 by GM7HHB. Runs on Windows XP and Vista. DStar TV

Home-brew D-Star radio

The first presumed D-Star radio including pictures and diagrams can be found at Moetronix.com's Digital Voice Transceiver Project. This page includes the schematic, source, and whitepaper.

Another project is Satoshi Yasuda's (7M3TJZ/AD6GZ) experiments with a UT-118 DV adapter. This project involves interfacing Icom's UT-118 with other manufacturer's amateur radio tranceivers. With this project some VHF/UHF/SHF amateur radio tranceivers are capable of being adapted for D-STAR operation. This requires access to the receiver's discriminator and to the direct FM modulator of the radio, sometimes available at a 9600 bit/s packet interface. See "Make the DV adapter using UT-118" for details. Sadly, Satoshi's product is no longer available. For an alternative, see http://www.dutch-star.nl

EA3CNO also has designed another interface based on a PIC microprocessor and UT-118 module see: "MODEM ADAPTADOR PARA DV" for details.

See also

• MDC-1200
• NXDN, a related commercial two-way digital radio standard with similar characteristics
• Project 25, a related digital radio standard sponsored by APCO
• Ricochet modems
• TETRA, a digital two-way radio standard in use outside of North America

References

1. "What is D-Star?". Icom America.
2. "About K5TIT - The Texas Interconnect Team". Texas Interconnect Team.
3. Bruce Perens. "The Codec2 Project: Next-Generation Audio Codecs and Vocoders for Two-Way Radio". Retrieved 2008-07-20.
4. http://icomamerica.com/en/products/amateur/dstar/dstar/default.aspx
5. "Amateur Equipment". Icom Worldwide.
6. "Amateur Equipment". Kenwood (Google Translation).
7. "DV Dongle Homepage". AA4RC.
8. "DVTool Software Download (Zipped)". AA4RC.
9. "Amateur Equipment". Moetronix.
10. ^ "3rd party". Icom America.
11. AE7Q. "3rd party sub: D-StarLet". Icom America.{{cite web}}: CS1 maint: numeric names: authors list (link)
12. http://www.d-rats.com/
13. The term "ratflector" was coined by James Deuel, N0XIA see http://lists.danplanet.com/pipermail/drats_users/2009-February/000850.html

Journal

Journals with D-STAR relevant information and a brief description

• ARRL: QST Special Emergency Communications Issue Vol 91 No 9 September 2007 Page 30, by Gary Pearce, KN4AQ talks about his experience using D-STAR followed by his comparison of the radio and conclusion. Page 109, by Icom describes D-Star used in EmComm.
• ARRL: QST Icom IC 2820H Dual Band FM Transceiver Vol 91 No 11 November 2007 Page 74, by Steve Ford, WB8IMY does a review on the IC 2820H Dual Band FM Transceiver.
• RSGB: RadCom March 2008 (Vol 83 No 03) review of Icom IC-E2820 transceiver and overview of D-Star.
• CQ-VHF: D-STAR in the Southeastern U.S., Greg Sarratt, W4OZK, (partial), http://www.cq-vhf.com/D-StarWin08.html

Media

Media with D-STAR relevant information and a brief description

• The Rain Report The Rain Report September 2007, by J. Maynard, k5zc The Rain Report discuss major concern in the D-STAR community

• Digital Voice for Amateur Radio, a documentary video produced in 2008 by Amateur Radio Video News . The hour-long video includes a 30-minute segment on D-STAR, including demonstrations and interviews with the amateur radio operators who helped introduce the new mode in America.

External links

• Alabama D-STAR Information
• D-STAR FAQ and Information
• Icom D-STAR information
• D-STAR in France
• D-STAR in Brazil

• Amateur radio
• Radio modulation modes