Save WSJT-X raw audio for data analysis

June 10, 2020

Upload raw .wav WSJT-X data to the HamSci Zenodo data archive to help future data analysis. The location of the WSJT-X raw data is found by the WSJT-X menu: File → Open Log Directory. The raw data save location is typically:

Windows: $Env:LocalAppData/WSJT-X/save
Linux: ~/.local/share/WSJT-X/save
macOS: ~/Library/Application Support/WSJT-X/save

To save the raw data, from the WSJT-X menu: Save → Save All. One .wav file is saved per two minute cycle. This setting is persistent.

Archive raw WSPR data for easier upload to HamSci Zenodo archive:

Upload raw data to Zenodo by creating a Zenodo account to upload WSPR data to Zenodo. Upon clicking “Publish” the data is assigned a DOI and is citable.

Tips:

Avoid using a virtual machine for WSJT-X due to issues with broken/choppy audio.
WSJT-X collects about 1.7 GByte/day depending on how often you transmit (no recording occurs when you transmit).
raw audio data file size is: 12000 samples/sec * 16 bits/sample / 8 bits/byte * 86400 sec/day * 0.8 RX duty cycle = 1.7 GByte / day. That’s 2.88 Mbytes per 2 minute WSPR RX cycle.
Since this is 6 kHz of spectrum, you can widen your receiver filters (particularly if using an SDR or other advanced receiver) to also pass JT65, FT8, or other useful transmitters for even more potent results that fall within the 12 kS/s sampling bandwidth.

The raw data .wav files are uncompressed PCM audio. “tar” is used to make one archive file instead of thousands of sound files per day. The files are full of noise, which by definition is poorly compressible.