Nexus 1.21.0 What's new in 1.21.0
Nexus is free amateur radio software for Windows, macOS, Linux and the Raspberry Pi. It decodes, logs, maps, raises alerts and shows the panadapter in one window, with one log, for one radio or up to three.
Free software under the GPL-3.0: nothing to buy and no account to make. Hamlib is inside every download, so rig control needs nothing else installed.
FT8 and FT4 follow WSJT-X's behavior, and JTAlert, GridTracker and your logger see Nexus as WSJT-X. CW, phone, RTTY, PSK31, SSTV, APRS, JS8, satellites and contests run in the same program and log to the same place.
Your habits carry over. Double-click a CQ to answer it, Esc stops TX, F4 clears the DX call and F6 decodes the last period again. Nexus sends the WSJT-X UDP messages, so JTAlert and GridTracker keep working, and companion mode can work from the decodes of a WSJT-X, JTDX or MSHV that keeps the radio. Import your log as an ADIF file and every station you have worked before shows a B4 mark.
The setup wizard asks for four things: your callsign and grid, the radio, your log and your license class. Detect my radio finds a USB rig or a FlexRadio on your network and fills in the port and the sound card. Your license class becomes a transmit lockout, so Nexus will not key outside your privileges.
A Technician license goes a long way here: satellites with rotor tracking, APRS, FM repeaters and the memory packs all work from the first launch.
Contest mode runs ARRL Field Day and Winter Field Day, Sweepstakes, the ARRL VHF contests, CQ World Wide, CQ WPX and six state QSO parties. The CW, RTTY and phone log strips have Enter Sends Message, Super Check Partial and the standard contest F-key layout. Club sync puts every laptop on the club's log, with a scoreboard made for a TV across the room.
Each of these is usually its own program. In Nexus they share one connection to the radio and one log.
| Job | In Nexus |
|---|---|
| Operate the modes | FT8, FT4 and the other WSJT-X modes, JS8, CW, SSB and FM, RTTY, PSK31, SSTV, APRS and our own TempoFast and TempoDeep. Every mode transmits as well as receives. |
| See who is on | Band Activity with each station's country and bearing, a call roster you can sort, the DX cluster and skimmer spots, and a 3-D globe with the greyline and live spots. |
| Hear about the ones you need | The Needed board ranks every station on the air by what it would add to your log, and each row shows who near you heard it and how long ago. A new one sounds an alert and can raise a desktop notification. |
| Log it and count it | One logbook for every mode. DXCC, WAS, WAZ, VUCC and IOTA are worked out from your own log on your own computer, with no account. Once you set up the connectors, contacts go to LoTW, QRZ, ClubLog and eQSL as you log them. |
| Run a contest | Contest mode with Enter Sends Message, Super Check Partial, dupe checking, a running score and Cabrillo export, and club sync for a multi-operator station. |
| See the band | The radio's own spectrum as a panadapter on Icom radios over CI-V and on FlexRadios, and a live audio scope on every other rig. |
| Find out why it is quiet | When nothing decodes, the readout says why: the radio on the wrong frequency, a closed squelch or a sound card that hears nothing. A wrong frequency comes with a Tune button that fixes it. |
| Program the radio | Repeater search, curated memory packs and a CHIRP CSV round trip. |
| Rule | What it means |
|---|---|
| It opens read-only | Connecting to the radio changes nothing on it until you act. A rig parked on 40 m LSB for a net stays there. |
| It transmits when you say so | Nexus never keys up on its own: TX is a switch you turn on. A watchdog stops a transmission left unattended for six minutes. |
| It holds you to your license | Your license class locks transmit out of the segments you are not licensed for, the 60 m channels included. |
| Your log stays on your computer | The logbook is a database on your own disk, with a plain ADIF copy kept up to date beside it and dated backups taken automatically. Awards are worked out locally. |
| Passwords stay in the keychain | Credentials for LoTW, QRZ, ClubLog and the other services live in your operating system's keychain and are never written to settings or logs. |
The core of Nexus and the part that is on the air every day.
The decoder is built from WSJT-X's own DSP sources, and on the same recorded audio it decodes down to −21.3 dB, against −20.7 dB for stock WSJT-X.
Icom radios over the network (receive and control only, for the IC-7610, IC-9700, IC-705, IC-905, IC-7760 and IC-7300MK2) and Nexus's own FlexRadio client.
Both are marked Beta in the app.
Our own weak-signal modes have completed real contacts on the air.
Their sensitivity figures still come from simulation, and on-air reports are what will replace them.
It is not code-signed yet, so SmartScreen warns on the first install: choose More info, then Run anyway.
The download page lists the SHA-256 of every file if you want to check yours.
The Mac build is for Apple Silicon and is signed and notarized.
Intel Macs can build Nexus from source.
Nexus 1.21.0
Windows · macOS · Linux · Raspberry Pi · GPL-3.0
Nexus is free and stays free. If it has earned a place in your shack, you can sponsor the project on GitHub. It pays for the build machines and for the code-signing certificate the Windows installer still needs.
Sponsor on GitHub ↗KD9TAW, licensed in 2021, who has operated DXpeditions to KP2 and VP2V and designed the TempoFast and TempoDeep modes. Nexus is the software on the air at the station it came from.