Winlink: Send Email Over Radio Without Internet

What Winlink Provides

During the first week after a major disaster, the critical communication problem is often not "I need to talk to someone" — it's "I need to get word to my family in another state that I'm alive."

Cell phones are down. Internet is down. The post office is either overwhelmed or operating at reduced capacity. Your family 1,000 miles away has no idea if you're okay.

Winlink solves this specific problem. One short email, transmitted over HF radio to a gateway, delivers to any email address in the world. Your family gets an email from you. They write back to your Winlink address. Their reply waits at the Winlink server until your next radio session picks it up.

This isn't theoretical. Winlink was used extensively after Hurricane Katrina, Hurricane Maria, and other major disasters where commercial communication was unavailable for days to weeks.

How Winlink Works

The architecture is simple. There are two types of stations in the Winlink network:

Gateway stations (WL2K CMS nodes): Amateur radio stations run by volunteers, connected to the internet. There are several hundred in North America. They receive your radio transmission, bridge your email to the internet, and store incoming messages for you to retrieve on your next radio session.

Client stations (your station): Your radio, a sound card interface, and a computer running Winlink Express. You connect to a gateway over radio, exchange emails, and disconnect.

Your Winlink address is your ham call sign followed by @winlink.org. Example: W1ABC@winlink.org. Anyone can email you at that address. Messages wait at the Winlink Common Message Server until you retrieve them via radio.

Equipment Requirements

Required:

• Ham radio (HF for long distance, VHF/UHF for local gateways)
• Ham radio license (Technician for VHF access, General for HF)
• Computer (Windows recommended; Mac and Linux via third-party tools)
• Sound card interface (SignaLink USB: $110-130, or DIY with audio cable: $5-10)
• Audio cables to connect radio to sound card interface

Software (all free):

• Winlink Express: The main Winlink client. Download at winlink.org. Handles email composition, gateway connection, and message storage.
• VARA HF or VARA FM: Digital modem software. VARA HF is the standard for HF connections ($69 for licensed version; free version works with reduced throughput). VARA FM is free and handles VHF connections.

Sound card interface importance: The interface connects your radio's audio input/output to the computer and handles PTT (push-to-talk) control. A dedicated interface (SignaLink USB) is more reliable than direct audio cables, reduces RF interference, and simplifies setup. Worth the cost.

VHF Winlink (Closer Gateways)

For Technician-licensed operators without HF capability, Winlink operates on VHF using VARA FM mode. Gateways within 10-50 miles can be accessed from a standard VHF radio.

Find VHF gateways: In Winlink Express, click "Update" in the gateway selector. A map shows all gateways within your specified range. Filter by "VHF."

Range: Approximately the same as a local VHF repeater — 10-50 miles with line of sight or a repeater. In a regional disaster, VHF gateways may be down if the affected area includes the gateway location. HF provides redundancy.

HF Winlink (National and International Coverage)

With a General license and HF radio, you can reach Winlink gateways anywhere in North America and internationally. Even if all gateways within VHF range are down (affected by the same disaster), HF gateways at 500-2,000 miles away are unaffected.

Band selection for Winlink:

• 40 meters (7 MHz): Primary emergency band, evening/night coverage across North America
• 80 meters (3.5 MHz): Regional night coverage
• 20 meters (14 MHz): International and long-distance daytime coverage

Winlink frequency lists by band are available at winlink.org/frequencies.

VARA HF modes: VARA Normal and VARA Robust. VARA Robust is slower but works in worse propagation conditions. Start with VARA Robust and switch to VARA Normal if conditions are good.

Setting Up Winlink Express

First test: Before any emergency, complete at least one successful Winlink session to confirm your setup works. Send a test email to your own email address from your Winlink address. Confirm receipt. Verify that replies appear in your Winlink inbox on the next session.

Winlink in Practice

Message size: Keep messages small — text only when possible. Each attachment dramatically increases transmission time. A short "I'm safe at [location], phone 555-0147" email is 500 bytes and takes under a minute. A message with photos takes 5-30 minutes at HF speeds.

Frequency selection: Use the Winlink gateway map in Winlink Express to find gateways. The software shows current gateway status and signal reports. Choose a gateway that has recent successful connections.

Radio discipline: Winlink shares HF frequencies with other amateur operations. Listen before transmitting. If the frequency is in use, wait. Winlink automatically follows operating procedure.

Position reports: Winlink Express can send your GPS position as part of a check-in. Emergency management agencies monitoring Winlink traffic can see your location. In a search-and-rescue situation, sending a position report via Winlink can bring help to your location.

Winlink vs. Voice Radio for Emergencies

These serve different purposes and both have value.

Voice radio is better for: Real-time coordination, back-and-forth conversation, getting immediate help.

Winlink is better for: Formal records, welfare messages to non-radio family, sending position/status to emergency management, receiving messages when you're away from the radio, messages that need to survive being written down.

An operator using both — voice radio for real-time nets, Winlink for welfare traffic and formal messaging — has the most complete capability. The combination is what ARES and RACES operators are expected to maintain.