Use digital modes

Radio Bench 1.0 supports RADE V1 digital voice receive and transmit. The mode selector shows its controls.

Digital voice

RADE (Radio Autoencoder) was originally created by Jean-Marc Valin and David Rowe as part of the FreeDV project. Radio Bench does not develop the RADE codec or waveform.

Use the mode passband that Radio Bench supplies. Confirm audio-device and transmit settings before on-air tests.

Receive RADE V1

1. Start a source and confirm that ordinary reception works.
2. Select RADE V1 in RADIO.
3. Tune to the other station's agreed dial frequency.
4. Keep the supplied fixed 3 kHz passband.
5. Allow the modem to acquire the signal, then listen through RX output.

RADE V1 uses lower sideband below 10 MHz and upper sideband at 10 MHz and above. Both stations must use compatible waveforms and tuning.

If the display shows a signal but speech is absent, check the mode and dial first. A visible signal does not establish modem synchronization.

Analog receive noise reduction and notch processing are bypassed in digital modes. Their settings remain stored. Dual-receiver mixing is also bypassed, so decoding continues from the SDR path.

Receive signal quality

In RADE V1 mode, the SNR meter below SDR RX shows the modem's signal-to-noise estimate. It uses the same visibility setting as the SDR signal meter. The reading clears when the modem loses sync and is inactive while stopped or transmitting.

Use SNR as reception feedback, not a guarantee that every word will decode. Check signal stability and clipping when acquisition repeatedly fails.

Transmit RADE V1

1. Complete transmit setup, including radio input and PTT checks.
2. Select RADE V1 and confirm the dial and sideband at the radio.
3. Select your speech microphone and the TX output connected to the radio.
4. Adjust input gain and compare the available input noise reduction.
5. Start PTT, speak normally, then stop PTT.
6. Wait for the normal transmit tail and confirm that the radio returns to receive.

The Audio workspace labels encoder input as TX SPEECH. It shows conditioned speech, not the encoded modem waveform or RF output. Analog voice compression controls are not the RADE transmit setup.

Ending a transmission

On a normal RADE transmit release, Radio Bench finishes queued speech and the end-of-transmission signal before releasing PTT. Faults and disconnections still stop transmission immediately.

FT8 and FT4

See the FSK operating guide for station setup, supervised exchanges, and logging.