Voice and Digital Modes - drexjj/zbitx GitHub Wiki

Voice & Digital Modes

This page covers SSB voice operation, the web interface (including transmitting voice from your phone/laptop microphone), and running third‑party digital software like WSJT‑X, JS8Call, and FlDigi.

SSB voice (USB / LSB)

Single‑sideband is the main voice mode on HF.

Set MODE to USB or LSB:
- USB — upper sideband, used on 20 m and higher by convention.
- LSB — lower sideband, used on 40 m and lower by convention.
Tune to a voice portion of the band (the phone segments, generally higher in frequency than the CW/digital segments).
Key up with your PTT and speak.

Getting good voice reports at QRP

Watch the Watts and SWR meters when you transmit — keep SWR under about 2:1.
Use the compressor (COMP in OPTIONS**)** to raise your average power — this noticeably improves readability at 5 watts.
TXMON (transmit monitor) lets you hear your own audio so you can check it sounds clean.
Speak close to the mic at a steady level; clean, well‑processed audio beats raw volume.

The web interface

The web interface is one of the zBitx's best features — it turns any phone, tablet, or computer into a full control head with a big screen.

Getting connected

Make sure the radio is connected to WiFi (or on your wired network).
Find the radio's address — it's shown on the front panel Wifi menu, or check your router.
Open a web browser on your device and go to the radio's address or use https://zbitx.local:8443
Log in with your passkey (set in Setup).

What the web interface gives you

Full tuning and control, including drag tuning on the spectrum.
Live spectrum and waterfall.
FT8 decode lists (Band Activity and RX Frequency), a grid map, and DX spot indicators — see FT8 Operation.
Watts and SWR meters during transmit, scaled for the 5‑watt QRP radio.
A panel to launch and control third‑party apps (WSJT‑X, JS8Call, FlDigi, and more).

Transmitting voice from your device

The web interface can use your phone/tablet/laptop microphone to transmit voice — so you can operate SSB remotely from another room or over the network, speaking into the device you're holding rather than a mic on the radio. This is great for casual operating and for reaching the radio when it's in a less convenient spot.

Running third‑party digital software

It is not recommended to install and run third-party applications on the Raspberry Pi 0 2W due to limited processing capability.

On an external computer (via USB CAT)

You can also connect an external PC and run your software there, using the radio's USB port in CAT mode for control. See USB Mode for how to switch the port to CAT.

CAT control (for logging and digital software)

The zBitx runs a built‑in hamlib‑compatible CAT server. Logging programs and digital‑mode software use CAT to read and set your frequency, mode, and PTT.

For software on an external computer, put the USB port in CAT mode (USB Mode) and point your program at it as a hamlib/rig‑control device.
Set the mode on the front panel to DIGI.

Which approach should I use?

You want to…	Best path
Casual FT8/CW without extra gear	Built‑in modes on the front panel
A big screen and remote voice TX	The web interface
Your favorite logger/software on a laptop like WSJT‑X/JS8Call/FlDigi/FreeDV	USB CAT mode to an external computer