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Quick Start — your first FT8 QSO in 15 minutes

This is the short path from a downloaded installer to a logged contact. The install step below is written for Windows; Linux and Raspberry Pi take the same path from step 2, and Install & Verify covers all three. It assumes a radio with a USB (or network) connection and a working antenna. Everything here is also covered in more depth in the user guide — this page is the fast lane.

By the end you will have Nexus installed, your station and rig set up, a cockpit full of live decodes, and one FT8 QSO in your log.

1.0.0 closes the beta period. The FT8/FT4 core is built to WSJT-X’s behavior and exercised on the air daily; it is the production part of the app. Where a number still comes from the bench rather than the air, these pages say so, and field reports are what close that gap.

1. Install and get past SmartScreen (about 3 minutes)

Download the file for your platform — Nexus_<version>_x64-setup.exe on Windows, Nexus_<version>_amd64.AppImage or Nexus_<version>_pc_amd64.deb on Linux, Nexus_<version>_pi_arm64_bookworm.deb / ..._trixie.deb on a 64-bit Raspberry Pi — from the SourceForge download page (the source lives there too). It is a per-user install and needs no administrator rights; WebView2 and Hamlib are bundled, so there is nothing else to install. Full detail, including SHA-256 verification and where your data lives, is in Install & Verify.

Run the installer. Because the binaries are cross-compiled and unsigned, Windows SmartScreen shows a blue “Windows protected your PC” dialog. This is expected. Click More info, then Run anyway.

If you would rather verify the download first, the release page publishes a SHA-256 for each installer — see Install & Verify.

2. The first-run wizard (about 4 minutes)

On first launch Nexus opens a three-step wizard: Station → Rig → Goals. Every step is skippable, and everything it sets can be changed later in Settings — you can reopen the wizard from Settings at any time.

Step 1 — Your station

Enter your callsign and grid square. The grid is the anchor for everything location-based: the propagation map, satellite passes, DXpedition windows, and the range rings all compute from it. Four characters (e.g. EN52) is plenty; the field turns red if it isn’t a valid Maidenhead locator.

Step 2 — Your rig

Plug in the radio, power it on, and click Detect my radio. One scan does two things at once: it enumerates USB devices and looks for FlexRadios on your network. What you see depends on the radio:

  • A named USB rig (Icom IC-705 / IC-7300 class, and other radios that report their model in the USB descriptor) shows up as a row like “IC-7300 on COM4” — one click fills the Hamlib model, serial port, and paired audio device together.
  • A bridge-chip cable (CH340, FTDI, CP210x, or Prolific reporting only “USB Serial”) can’t tell Nexus what radio is on the far end. The row fills the port and audio and names the chip, but leaves the model blank — pick your rig from the dropdown. If Windows is missing the chip’s driver, Nexus shows the download link.
  • A FlexRadio on the LAN shows up as “FLEX-6400 on the network”. One click configures the WSJT-X-proven path — CAT through the SmartSDR CAT app on this PC (127.0.0.1:5002, slice A) — and offers a ⚡ Pair DAX audio button for the virtual audio devices.

Then click Test CAT. Nexus saves what you’ve entered, starts its bundled rigctld, and reads back the dial frequency. A number like 14.074 MHz means CAT is working. If it fails, Troubleshooting → CAT walks through the usual causes.

Step 3 — Your goals

Pick one or more goal cards — Just getting started, DX chasing and awards, Contesting, POTA / SOTA, 6m / VHF — and Nexus turns on the matching features (you can toggle any of them later). Digital (FT8/FT4) is always on; check Phone or CW if you operate those modes.

Finally, declare your license class (Technician / General / Amateur Extra, or Outside the US for no limits). This becomes a real Part 97 transmit lockout — the software refuses to key outside your privileges, including the 2026 60 m rules. It’s a safety net, not a substitute for knowing your license.

Click through, and Nexus drops you into the digital cockpit.

3. A tour of the digital cockpit (about 2 minutes)

Out of the box the dial sits at 14.074 MHz (FT8, 20 m), decode depth is Deep, and the decoder listens across 200–2900 Hz. Decoding runs every RX slot automatically — there is no Monitor toggle to forget.

The three things to know:

  • The waterfall across the top shows signal energy over frequency. Click it to move your RX (and TX) marker.
  • Band Activity is the decode list — newest at the bottom, auto-scrolled to the latest period. Every row carries what stock WSJT-X never showed: the country name, a B4 chip if you’ve worked them before, New DXCC / new-grid badges when a station is worth something to your log, and a teal L if they upload to LoTW. Rows calling CQ, and rows calling you, are flagged. Scroll up to review and auto-scroll pauses; scroll back down to resume.
  • The Classic ↔ Roster toggle switches between the familiar stock layout (with the Tx1–Tx6 panel and editable DX Call/Grid) and a modern sortable call roster. Use whichever you like.

The TX controls — TX On/Off · Tune · Stop TX · Hold Tx — sit in the QSO strip next to Call CQ and S&P. Nexus never transmits on its own; TX is always something you switch on.

4. Answer a CQ (about 1 minute of watching)

  1. Find a station calling CQ in Band Activity.
  2. Double-click the row. Nexus arms the sequencer, sets your slot parity, and fires the first transmission at the next period. From there it runs the whole exchange for you — grid → report → R-report → RR73 → 73 — advancing on what the other station actually sends back. It locks onto that station, so a report from a bystander won’t derail your QSO.
  3. Watch the Tx panel to see which message goes out next. That’s it — you’re making the contact while you learn the rhythm by watching.

A single click just fills the DX Call/Grid fields without transmitting. Esc halts TX instantly. F4 clears the DX call, F6 re-decodes the last period for a second look.

Two reassurances while you find your feet:

  • The license lockout has your back. If the dial is outside your declared segment, the TX button shows a lock and the engine refuses to key — you can’t accidentally transmit out of band.
  • The TX watchdog is watching too. After 6 minutes of unattended transmit the engine halts itself, so a walk-away never leaves you keyed down.

5. Logging, and what the Needed board starts telling you

When the QSO completes it is logged automatically (auto-log is on by default) and pushed to PSK Reporter — and, once you configure them, to QRZ and LoTW. Your logbook is a standard ADIF file; importing an existing log credits your history immediately.

With a callsign and grid set, the Needed board begins ranking every station on the air by what it’s worth to your log — an all-time-new entity outranks a new zone, which outranks a new band, and so on. What makes it trustworthy is the evidence line on every row: who near you heard that station, how far away, and how long ago. One click there QSYs the rig to the right band, mode, and frequency and opens the matching cockpit.

Where to go next

You’re on the air. When you want to go deeper, each section has its own guide:

Stuck on something? Start with Troubleshooting.

This page is synced from docs/quick-start.md in the Nexus repo. Corrections belong there.