What is FT8 in ham radio?

FT8 is a digital communication mode designed by Joe Taylor (K1JT) and Steve Franke (K9AN). It uses 15-second transmit/receive cycles to exchange callsigns, grid squares, and signal reports. FT8 can decode signals as weak as -21 dB — far below what human ears can hear — making it ideal for low power (QRP) and compromised antenna setups.

What software do I need for FT8?

The standard software is WSJT-X, which is free and available for Windows, Mac, and Linux. You also need a way to connect your radio's audio to your computer — either a dedicated digital mode interface (like SignaLink USB or Digirig) or a USB cable if your radio has a built-in sound card (most modern radios do).

What are the FT8 frequencies?

Standard FT8 frequencies (dial frequency, USB): 160m: 1.840, 80m: 3.573, 60m: 5.357, 40m: 7.074, 30m: 10.136, 20m: 14.074, 17m: 18.100, 15m: 21.074, 12m: 24.915, 10m: 28.074, 6m: 50.313, 2m: 144.174. Set your radio to USB on these frequencies.

FT8 Getting Started — Digital Mode Guide for Ham Radio

The digital mode that changed ham radio — make contacts worldwide with 5 watts and a wire antenna

What is FT8?

FT8 (Franke-Taylor design, 8-FSK modulation) is a digital mode that exchanges callsigns, grid squares, and signal reports in 15-second cycles. Your computer encodes your message into audio tones, your radio transmits them, and the receiving station's computer decodes them — even at signal levels far below the noise floor.

FT8 can decode signals at -21 dB SNR. That means contacts that are impossible on SSB or CW become routine. This makes FT8 ideal for QRP (low power), compromised antennas, and marginal band conditions. It's now the most popular mode on HF by activity volume.

What You Need

Hardware

- HF transceiver — Any rig with USB mode. Even older rigs work fine.
- Computer — Windows, Mac, or Linux. Even a Raspberry Pi works.
- Audio interface — connects your radio's audio to your computer:

Option A: USB cable — If your radio has a USB port (Icom IC-7300, Yaesu FT-991A, most modern rigs), just connect via USB. Audio and CAT control over one cable.

Option B: External interface — SignaLink USB, Digirig Mobile, or similar. Connects between your radio's audio jacks and your computer's USB port.

Software (All Free)

- WSJT-X — The standard FT8 software by K1JT. Handles encoding, decoding, and logging.
- JTAlert (optional, Windows) — Alerts you to new DXCC entities, states, and needed contacts.
- GridTracker (optional) — Shows FT8 contacts on a world map in real-time.

FT8 Frequencies

Set your radio to USB on these dial frequencies. WSJT-X handles the audio offset.

Band	Dial Freq (MHz)	Best Time
160m	1.840	Night (local)
80m	3.573	Evening/Night
40m	7.074	Afternoon/Evening
30m	10.136	All day (quiet band)
20m	14.074	Daytime (busiest band)
17m	18.100	Daytime (SFI > 100)
15m	21.074	Daytime (SFI > 120)
12m	24.915	Solar max only
10m	28.074	Daytime (SFI > 130)
6m	50.313	Sporadic E (summer)
2m	144.174	Tropo/meteor scatter

Check our Propagation Dashboard to see which bands are open right now. The current SFI determines which higher bands are usable.

Setting Up WSJT-X

1. Download WSJT-X — Get the latest version from physics.princeton.edu/pulsar/k1jt/wsjtx.html. Install it.
2. Set your callsign and grid — File → Settings → General tab. Enter your callsign and Maidenhead grid square. Use our Grid Square Tools to find your grid.
3. Configure audio — Settings → Audio tab. Select your radio's USB audio device (or SignaLink) for both input and output.
4. Configure CAT control — Settings → Radio tab. Select your rig type, serial port, and baud rate. Click "Test CAT" — the button should turn green.
5. Sync your clock — FT8 requires your computer clock to be accurate within 1 second. Use Meinberg NTP or Windows time sync. A 2-second offset and nobody will decode you.
6. Set your power — Start with 5-10 watts. FT8 doesn't need power. Running 100W is antisocial unless you're chasing rare DX.
7. Select FT8 mode — In the main window, select "FT8" from the Mode menu. Set your band frequency.

Your First FT8 QSO

1. Listen first — Set your radio to 14.074 (20m), USB. Watch the WSJT-X waterfall. Within 15 seconds, you should see decoded callsigns appearing in the left panel.
2. Check your timing — The DT column shows time offset. If your decodes show DT values larger than +/- 1.0 second, fix your clock.
3. Double-click a CQ — When you see a station calling CQ (e.g., "CQ DL1ABC JO31"), double-click their line. WSJT-X automatically queues your response.
4. Let the software work — WSJT-X handles the entire exchange: your call, their signal report, your signal report, acknowledgment. Each step takes 15 seconds.
5. Complete the QSO — A complete FT8 contact takes about 1 minute (4 transmit cycles). When you see "73" (best regards), the QSO is complete and logged.

Common Mistakes

- Clock is off — The #1 problem. FT8 needs sub-second accuracy. If nobody decodes you, check your clock first.
- Audio levels too high — Overdriving your transmit audio creates splatter. Keep the ALC meter at zero or barely moving. Use the WSJT-X power slider to reduce audio output.
- Running too much power — 5-10W is plenty for most FT8 contacts. 100W on FT8 is like shouting in a library.
- Wrong sideband — FT8 uses USB on all bands, including 160m and 80m (unlike SSB conventions).
- Transmitting on top of others — WSJT-X picks a clear frequency in the waterfall. Don't manually set your TX frequency on top of an existing signal.
- Expecting a ragchew — FT8 exchanges minimal information: callsigns, grid, signal report. That's it. It's not a conversation mode.

FT8 and Propagation

FT8's weak-signal capability means you can work DX that SSB operators can't even hear. But you still need propagation. Use our Propagation Dashboard to check current solar flux (SFI) and band conditions. Higher SFI means more bands are open. The RBN Explorer shows real-time CW and FT8 spot density by band — a direct measure of what's actually working right now.

Check Band Conditions RBN Explorer Find Your Grid Square

FT8 Getting Started Guide