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What is Winlink?

Winlink is a worldwide system for sending and receiving e-mail via radio. Winlink provides e-mail from almost anywhere in the world, using a well-tested and full featured system. Its been adopted for contingency communication by many federal, state and county government agencies, including the National Guard, and infrastructure-critical NGO's such as International and American Red Cross, Southern Baptist Disaster Relief, DHS Tiered, AT&T Disaster Response and Recovery, FedEx, Bridgestone Emergency Response Team, and many more.

Winlink Networks include:

Amateur Radio - Over 10,000 Amateur Radio users are registered.

Maritime - Winlink is used by most off-shore sailors, operating within the international amateur radio frequency space.

SHARES - Federal system providing HF radio contingency communication for federal agencies. SHARES operates on NTIS federal frequencies that are not part of the amateur radio frequency space.

MARS -  The Military Auxilliary Radio Service provides contingency communication for the United States Military, operating within NTIS MARS radio frequency space.

What Winlink offers for EmComm:
  • Reliability, Accuracy and Flexibility:
  • High reliability (99.99% availability for 15 years)
  • 100% accurate message transmissions.
  • Radio connection bridge to Internet e-mail
  • Radio-only store and forward without Internet
  • Geographical dispersion and redundancy for reliability
  • Peer-to-peer connections between radio end-users
  • Various levels of security including message encryption
  • Interoperability: Connect different types of systems
  • Bridge different radio capabilities (VHF/UHF/HF)
  • Bridge protocols: Pactor, Winmor, Ardop, VARA, Packet.
  • Standard e-mail format with many features
  • Binary file attachments (pictures, pdf, spreadsheets)
  • Automatic message compression/decompression
  • Encrypted attachments using the encryption program you choose. 
  • Time independence and frequency agility
  • Not limited by station-to-station propagation

Winlink System Components

Client system
– Radio, computer with Winlink Express software, TNC (or sound card) and you, the end-user!

Radio Message Server (RMS)
– Radio gateway between the client (end-user) and the Winlink system backbone.

Common Message Servers (CMS)
– Winlink backbone.
  • Multiple CMS locations.       
  • Redundant, fault-tolerant
  • Located on 3 continents
  • One CMS is sufficient for normal system operation.

Winlink Connection Modes
  • HF Pactor – Fast but expensive
  • HF WINMOR – Much slower, but reliable (Sound card mode)
  • Ardop and VARA – Faster alternatives to WINMOR
  • VHF/UHF Packet – 9600 baud
  • Telnet – Non-radio connection through the Internet.
  • Iridium GO! – Satellite phone connection.
  • MESH network to Winlink “Post Office” (RMS Relay).
  • Telnet peer-to-peer between to Winlink Express users.

Ardop TNC
Screen Capture of Ardop Virtual TNC with active waterfall

First Steps

Get a Winlink Account
  1. Download, install and configure Winlink Express (or other client program)
  2. Connect with the system (send a message) to create your account. Your radio email address is
  3. Use the form (lower right) to have a password sent to your new address. Retrieve it using your client program.
  4. Use your callsign as your username, and password to log in here.

Winlink accounts stay alive only with radio use. Accounts off-air for 400 days are automatically purged. Use it or lose it!

Winlink Express Email Client

Winlink Express (formerly RMS Express) is the preferred Winlink radio email client because it supports all new system features, including the Winlink Hybrid Network and Secure Login to help prevent unauthorized access to your account.

Winlink Express

Setup your station

Winlink Express is designed to be easily used by single users with a single call sign but it may also be used to simultaneously send and receive mail with one or two tactical addresses or alternate Winlink accounts. It supports a wide selection of transceivers, TNCs and multimode controllers, the sound card modes WINMOR, Ardop, and VARA using virtual TNCs, HF Pactor, SCS Robust Packet, VHF/UHF AX.25 packet radio, and direct telnet to CMS servers or RMS Relay (for amateur radio High Speed Multimedia [HSMM], Broadband HamNet, D-Star DD mode, internet, and other TCP/IP networks).

The most common setup for ham radio operators is to use a PC or laptop, with the Winlink Express client installed, and a sound card interface such as a Signalink USB or Rigblaster, connected to your HF transceiver. This is familiar to anyone who uses narrow band or low-power digital modes with programs such as FLDigi or WSJT-X.

Once you get your station setup, send a message to Steve KB1TCE on Winlink and ask to be included in his Weekly Winlink Exercises. This is a fun way to learn about different features of the program and test your equipment on a regular basis.

Additional Resources

An excellent document about Winlink equipment configurations, including diagrams, can be found here - The document, by N5TIM, is recommended by the ARRL NTX SEC.

Click on the links below to learn more about Winlink, and how to get started:

There will be some additional setups required to get the program working correctly with your particular transceiver, interface, or TNC. To help you with these, visit, where you'll find links to various help blogs and discussion groups.


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