What Is FT8? A Beginner's Guide to Your First QSO with WSJT-X

The bands sound dead, nobody answers your phone CQ, yet the waterfall is full of signals. Welcome to FT8. Since its release in 2017 this digital mode has become one of the most common ways hams make contacts on HF. In this post we explain what FT8 is, why it caught on so quickly, and how to make your first QSO with WSJT-X step by step.

What Is FT8 and Why Is It Everywhere?

FT8 is a weak-signal digital mode developed by Joe Taylor (K1JT) and Steve Franke (K9AN). The name comes from "Franke-Taylor design, 8-FSK modulation". It ships as part of the free, open-source WSJT-X software package.

What makes it stand out:

• It decodes very weak signals: signals around -20 dB in a 2500 Hz reference bandwidth, well below what your ears can hear, can still be decoded.
• It is narrow: each signal occupies roughly 50 Hz, so dozens of stations fit inside a single SSB channel.
• Short, fixed timing: every transmission lives in a 15-second slot, and a complete QSO usually takes a minute or two.
• Great at low power: a simple dipole and a few tens of watts can work other continents, which makes it a favourite for hams with balcony antennas and restricted setups.

The trade-off is that FT8 is not a ragchew mode. Messages are tiny and limited to callsigns, grid squares, signal reports and "73". You get a quick, reliable logged contact rather than a conversation, which is exactly what DX, award and new-country hunters want.

What You Need

You do not need an expensive station. The basics are:

1. An HF transceiver that can operate in USB. Digital modes run at a 100% duty cycle during transmit, so keep the power sensible.
2. A computer running Windows, Linux or macOS, or even a small board like a Raspberry Pi.
3. An audio interface: many modern radios have a built-in USB sound card, so one cable carries both audio and CAT control. Older rigs can use an external interface such as a SignaLink-style box.
4. An antenna suited to your band with a reasonable SWR. Our earlier posts on SWR and grounding apply here too.
5. Accurate time: non-negotiable. Your computer clock should be correct to well under one second.

Installing and Configuring WSJT-X

Download WSJT-X only from the official project page: wsjt.sourceforge.io. After installing, open File > Settings.

General tab

Enter your callsign and your 4-character grid locator (for example KM38 around İzmir). Plenty of online tools will calculate it from your address.

Radio tab

Pick your rig from the list and match the COM port and baud rate to your radio's menu. For PTT, CAT is usually the cleanest option. If Test CAT turns green, you are connected.

Audio tab

Select the radio's USB audio device for input and output. Levels matter a lot:

• On receive, the level meter at the bottom left should sit around 30 dB on a quiet band.
• On transmit, the radio's ALC should barely move. Overdriving the audio distorts your signal and splatters onto neighbouring frequencies.

Time sync

On Windows, Meinberg NTP or a similar NTP client works well; on Linux use chrony or systemd-timesyncd. If the "DT" column of decoded stations consistently shows values close to one second, your clock is drifting.

FT8 Frequencies

FT8 activity gathers on widely agreed "dial" frequencies. Set your radio to USB on that frequency; your actual signal sits 200–3000 Hz above it depending on the audio tone.

Which bands and power levels you may use depends on your licence class, so always check the current BTK regulations and the IARU Region 1 band plan.

Your First FT8 QSO, Step by Step

Start by just listening for a few minutes. Signals will appear on the waterfall and decodes will scroll in the left window. A typical exchange looks like this:

Practical tips:

• Answer someone else's CQ first: double-click a CQ line and WSJT-X prepares the whole sequence and enables Tx.
• Choose your own spot: turn on "Hold Tx Freq" and park on a clear area of the waterfall. Transmitting right on top of the station you call makes life harder for everyone.
• Mind even and odd slots: the software handles this, but when calling CQ manually avoid clashing with a strong station using the same slot.
• Don't overdo the power: 100 W is rarely needed. Twenty to forty watts and a decent antenna usually do the job, and your radio will thank you.
• Keep your log: WSJT-X writes every QSO to an ADIF file you can import into Wavelog or Log4OM and upload to LoTW or QRZ.

Common Mistakes and Etiquette

• Clock errors: if nobody ever answers, check your clock first.
• Too much audio: if you see ghost copies next to your signal on the waterfall, turn the drive down.
• Endless repeats: if the other station can't hear you, pause and try again later instead of sending the same message for minutes.
• DXpedition rules: when a rare station runs Fox/Hound mode, follow their published instructions and call in the indicated range.
• Unattended operation: transmitting fully automatically with nobody at the station can breach both etiquette and licence conditions. Stay at the controls.

Summary

Cover photo: bollvils / Pixabay