Ham Radio VoIP

and the Digital VoIP Multimode
Interlink System

Jeffrey Kopcak - K8JTK
ARRL Ohio Section Technical Coordinator

Technical Coordinator

The ARRL Technical Coordinator (TC) is a section-level official appointed by the Section Manager to coordinate all technical activities within the section.

  • Supervise and coordinate the work of the section's Technical Specialists (TS)
  • Refer amateurs in the section who need technical advice to local TS
  • Encourage amateurs in the section to share their technical achievements with others through the pages of QST, at club meetings, hamfests, and conventions

Technical Coordinator

  • Be available to assist local technical program committees in arranging suitable programs for local club meetings, ARRL hamfests, and conventions
  • Promote technical advances and experimentation at VHF/UHF and with specialized modes, and work closely with enthusiasts in these fields within the section

Technical Specialist

For a section team to be effective in one of the most important arenas in Amateur Radio, technology, there must be a cadre of qualified, competent Technical Specialists (TS).

"Advancement of the radio art" is a profound obligation we incur under the rules of the FCC.

TSes help meet this obligation.

Technical Specialist

TS supports the TC in two main areas of responsibility:
Radio Frequency Interference and Technical Information.

Technical Specialist can specialize in certain specific technical areas, or can be generalists.



  • What is VoIP?
  • Analog systems
  • Digital systems
  • Software used
  • Connection links
  • Dashboards & diagrams
  • Problems
  • Nets

What is VoIP?

Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.

Ham VoIP

  • New, as of about 2002
  • Networks or Internet for long distance communication, not ionosphere
  • Mostly 2m or 440, some 220 & 6m (VHF/UHF)
  • Repeaters and simplex node linking, some user/non-RF
  • Internet-aided DXing for Technicians, not interested in HF, not capable
  • Occasionally called "RoIP" for Radio over IP, at least one radio device has an IP connection
  • Mostly independent, own islands

Ham VoIP - Analog Systems

  • Echolink
  • iLink
  • eQSO
  • IRLP
  • AllStar Link
  • WIRES-X (both)
  • Hamshack Hotline


  • Common install:
  • PC/Pi running Windows/Linux
  • Interface: circuit, audio FOB, RIM, URI, RTCM (EOL), HRI, ...
  • Transmitter: repeater, link/simplex radio, or none (radio less)
  • Access other nodes: DTMF

img: DMK Engineering


img: Echolink

  • Early 2002 by Jonathan - K1RFD
  • Quick adoption. 30,000 nodes ~1 yr
  • User = K8JTK, Link = K8JTK-L, Repeater = K8JTK-R, Conference = *DVMIS*
  • Port forwarding (firewall), specific ports. One node per IP.
  • Proxies
  • Closed source, reverse engineering OK
  • Resurgence mobile apps
  • Echolink. Windows, OS X, Qtel (Linux), SVXLink, Android, iOS


  • Started 1997 by Dave - VE7LTD
  • Only accessible via radios
  • node -> node or node -> reflector
  • Approved or specialized hardware required, source of income
  • Linux install. Closed source. Network tightly controlled.
  • NO experimentation. Booted reverse engineering, cross connecting modes.
  • EchoIRLP - Echolink or IRLP, not both same time
  • Experimental reflectors, 2018
  • IRLP

AllStar Link

  • AllStar - open-source PBX Asterisk, Linux
  • AllStar Link - network, phone directory
  • Started 2008 by Jim - WB6NIL (SK)
  • app_rpt module designed as repeater controller
  • Public Internet or private network
  • Multiple nodes on single IP
  • Every node is a reflector, multiple connections
  • Can be radio-less
  • Stability issues: software, network, foundation
  • Native support: Echolink, IRLP (until removed), D-STAR w/ DNGL
  • AllStarLink

HamVoIP & PTTLink (ASL forks)

  • Low adoption AS/ASL
  • HamVoIP: 2014 by Doug - WA3DSP & David - KB4FXC
  • Forked project: built-on and fixed ASL issues
  • Raspberry Pi only
  • Compatible with AS & ASL
  • NOT open-source! Changes unclear.
  • Grew AllStar popularity
  • HamVoIP
  • PTTLink: more drama
  • Near as I can tell: ousted crew from ASL project end of 2020
  • Forked the network
  • Compatible with AllStar, not AllStar Link
  • < 20 active nodes
  • PTTLink


  • Wide-coverage Internet Repeater Enhancement System by Yaesu
  • WIRES (beta), WIRES-II (until 2017), WIRES-X
  • Proprietary network and hardware to Yaesu
  • Analog possible non-Yaesu equipment. Digital ONLY on Yaesu C4FM capable radios & repeaters.
  • Windows ONLY!
  • YSF/YSFReflector = Open-source reflector & linking system
  • WIRES-X/WIRES-X rooms = Closed-source system for Yaesu

Hamshack Hotline

  • Not a radio linking system
  • Started 2018 John – K1WIZ
  • Uses Asterisk
  • Requires a SIP (Cisco) phone & Internet connection
  • Full duplex, direct dialing, voice mail, notifications, conference rooms, ...
  • Popular in EOCs
  • Experimental server non-supported devices, "on your own"
  • HH users can dial into Radio Services
  • Range: $20 - $50
  • Hamshack Hotline

Ham VoIP - Digital Systems

  • D-STAR
  • DMR
  • System Fusion
  • NXDN
  • P25

img: QRZNow


img: ICOM

  • Common install:
  • Gateway software for routing
  • Interface: controller, MMDVM board, DV4Mini, DVMega, OpenSpot, dongle, HRI, ...
  • Transmitter: repeater, hotspot, link radio, or none at all (radio less)
  • Access other nodes: structured control system (TG, Reflector, Room, ...)
  • Apps: DUDE-Star (Win), DROID-Star (Android)


  • Digital Smart Technologies for Amateur Radio
  • Developed late 1990s by Japan Amateur Radio League
  • First designed for ham radio
  • Open protocol, proprietary codec
  • Simultaneous voice & data
  • Network, D-RATS
  • High-speed data (128 kbps), not used
  • Registration
  • HF, VHF, UHF, SHF. Satellites.
  • ICOM & Kenwood (exiting?)
  • Useless manual
  • Range: $300 - $1300

img: ICOM


img: Hytera


  • Registration required
  • DMR-ID is NOT a callsign!
  • Programming requires computer
  • VHF & UHF (inc 900 MHz)
  • TYT, Connect Systems, Bridgecom, Alinco, Motorola, or any Tier-2 radio
  • Range: $90 - $750

System Fusion

  • Released in 2013 by Yaesu
  • Easiest to use
  • Proprietary standard & codec
  • "Eternal beta" - redesigns, repeater issues, firmware, ...
  • Compatible with analog
  • VHF & UHF
  • Yaesu - single manufacturer
  • Cheap repeaters, "promo"
  • WIRES-X linking
  • Range: $175 - $1200

NXDN & P25

  • NXDN: ICOM & Kenwood in 2005
  • P25: collaboration started 1989
  • Public safety
  • Motorola, Kenwood, Tait, EFJohnson, ...
  • Both: open standards
  • Adopted by ham radio

img: Wikipedia


The goal here should be to kick the proprietary protocols off the airwaves, replace DMR, Fusion, D-Star, etc. To do that, it’s not just good enough to be open, it has to be legitimately competitive.
  • Started 2019
  • Freely available and modifiable digital radio protocol, open hardware
  • Codec2
  • Needs ALOT of work
  • M17

TeamSpeak, Zello, ...

  • Non-ham specific
  • Some commercial
  • Don't have to be licensed
  • Linked to transmitters, unlicensed violations
  • Banned on some networks (Brandmeister)

Is VoIP ham radio?

  • Nooooo shortage of opinions
  • Both ends a radio
  • Younger and older hams alike finding uses


Digital VoIP Multimode
Interlink System
(K8JTK Hub)

Why, in the world...?

  • Ham radio experimentation
  • Support open source projects
  • Interlink ham radio VoIP modes for interoperability
  • Utilize ham radio spectrum
  • Reliable and resilient - hardware, power, weather
  • Fairly inexpensive (COM compliant?)

Packages: AllStar Link

AllStarLink is a world wide network of Amateur Radio repeaters, remote base stations and hot spots accessible to each other via the Internet and/or private IP networks
  • Open-source PBX Asterisk
  • Linux (including Raspberry Pi)
  • Jim Dixon - WB6NIL (SK)
  • app_rpt module - repeater controller
  • AllStarLink

img: luis gomes

Packages: G4KLX

Programs that support D-Star, DMR, System Fusion, P25, NXDN

  • Jonathan - G4KLX
  • ircDDBGateway, NXDNReflector, NXDNGateway, P25Reflector, P25Gateway, YSFReflector
  • MMDVM implemented in devices, boards, hotspots like Pi-Star and OpenSpot
  • github: G4KLX

Packages: DVSwitch

Tools and programs related to provisioning and operating Amateur Radio digital voice networks

Packages: XLXD

XLX Multiprotocol Gateway Reflector Server is part of the software system for the D-Star Network

  • Jean-Luc - LX3JL & Luc - LX1IQ
  • Four D-STAR reflector protocols: REF, XRF, DCS, XLX
  • XLXD speaks all four protocols +
  • DMR and YSF transcoding (not used, additional hardware)
  • github: XLXD

Packages: thebridge

CQiNet is a family of programs that combine Ham Radio with the Internet using Voice over IP (VoIP) technology

  • Skip - WB6YMH & others
  • EchoLink compatible conference bridge
  • Sourceforge: Thebridge

Packages: HBLink3

...we have an open protocol for internetworking DMR repeaters. Unfortunately, there's no generic client and/or master stacks. This project is to build an open-source, python-based implementation.

  • Randy - AA6RH
  • Open Source HomeBrew Repeater Protocol Client/Master
  • github: HBLink3

Packages: mrefd

An M17 Reflector.

  • Tom - N7TAE
  • Open Source M17 reflector based on XLXD
  • github: mrefd

Packages: USRP2M17

... converts USRP PCM audio and M17 digital mode ...

  • Doug - AD8DP
  • Part of MMDVM_CM - cross-mode conversion for some digital voice protocols, based on Jonathan G4KLX's MMDVM software.
  • github: USRP2M17

Putting it together

Chicago data center

  • Three VPSes (virtual private servers)
  • Linux Debian OS
  • Low latency to remote hardware

Remote hardware

  • Twelve different networks! Nine full-time modes!
  • Any user on one network can communicate with users on any other
  • AllStar is the "Hub", individual nodes for control

img: Pixabay

DVMIS: The Nodes

  • AllStar Link: 50394
  • DMR: Brandmeister Talkgroup (TG) 3172783
  • DMR: TGIF Talkgroup (TG) 31983
  • D-STAR: XLX983A - "A" for Analog Bridge
  • EchoLink: *DVMIS* 600008
  • Hamshack Hotline: 94026   *99 - TX, # - RX
  • M17: M17-983A
  • NXDN: TG 31983
  • P25: TG 31983
  • YSF: K8JTK-Hub 31983
  • Wires-X: K8JTK-ROOM 40680

Info on connecting, systems, radios, status, and more: DVMIS @ K8JTK.org

DVMIS: Dashboards

img: freestocks.org


  • Follow all rules of your regulatory authority
  • Keep it classy
  • English only
  • Identify your station by voice. Digital stations are used to quick-keying to break-in or check-in, this will not work. IDs in data streams are lost due to analog and cross-linked connections. Users on non-radio VoIP solutions tend to forget they’re on a radio system. Proper ID is required and accepted method is by voice.


  • Press PTT and pause for 2 seconds before speaking. This gives time for all links to become operational otherwise, the first couple words of the transmission will be lost.
  • Pause a minimum 3-5 seconds between transmissions. Stations cannot break-in when stations quickly key-up (or "tailgate") after the previous. System timeouts are caused when links are not given proper time to reset.

Pretty pictures:
Logical connections

Pretty pictures:
IP connections



  • IP based, keeping all the ports straight!
  • 😞 Dependency hell: addons and changes to programs
  • Protocol and implementation changes: XLX & YSF, YSF choose reflector number
  • DVSwitch implementation rewrites: 2x already
  • 😠 Data Center provider: packet loss, "internal problems" - 1 move
  • D-STAR hardware. Codec: "you won't be happy"
  • D-STAR & M17 LOOOOOVES IP addresses
  • D-STAR Analog Bridge choppy audio with AMBED
  • AllStar compiling
  • 😡 AllStar chan_echolink module. Kill me now.


  • WCARA (WC8VOA) Club net: Mondays @ 8pm-9pm
  • AmateurLogic.TV Sound Check net: Tuesdays @ 9pm-midnight
    Huge thanks for ALTV being a test of the system!

Last Man Standing SE - KA6LMS

  • Multimode QSO Party sponsored by: AmateurLogic.TV
  • Part of the week-long event commemorating nine seasons of LMS
  • WAY more popular than anticipated!
  • 8.5 hours!
  • 300 counted stations, 500 total
  • 20GB traffic
  • Recap


Jeffrey Kopcak - K8JTK

ARRL Ohio Section Technical Coordinator

- K8JTK@arrl.net
- Contact me for nets or other uses of DVMIS
- This presentation is available on my website under the "Presentations" category: K8JTK.org


  • AllStar: 50394
  • DMR: BM TG 3172783
  • DMR: TGIF TG 31983
  • D-STAR: XLX983A
  • EchoLink: *DVMIS* 600008
  • Hamshack Hotline: 94026
  • *99 - TX, # - RX
  • NXDN: TG 31983
  • M17: M17-983A
  • P25: TG 31983
  • YSF: K8JTK-Hub 31983
  • Wires-X: K8JTK-ROOM 40680

Local meeting:

  • Analog (ASL): 446.975 simplex, no PL
  • Hotspot 1 (YSF): 433.125
  • Hotspot 2 (D-STAR): 445.050

AllStar Dashboard

Info on connecting, systems, radios, status, and more: DVMIS @ K8JTK.org