This month I finished the RADE V2 stored file test campaign, and have collated the results. We have obtained a similar ranking to the simulations, with V2 preferable to V1, and both well ahead of SSB. Thank you once again to the Hams who kindly contributed to this work.

The majority of the work this month was spent writing a paper on RADE V2, to document the new innovations in the mode and the algorithms used (documentation to professional level is one of our ARDC grant aims). As I developed RADE V2 over a period of 18 months I had forgotten some of the finer details. This development was mainly a solo effort, so looking at it again after a year served as a form of self-review. Development of RADE V2 was particularly challenging due to the lack of pilot and unique word syncronisation symbols. The paper is now in rough draft form.

Some of the algorithms were developed working with Claude code. To my surprise we couldn’t find a reference to one of the algorithms (end of over detection) anywhere in the literature. This suggests it was unique algorithm development by Claude! It certainly didn’t come from me, although I understood the principles when Claude suggested it and we worked together to devise suitable tests with good overall results. I will perform a broader literature search to see if I can find anyone else using similar ideas

In July I plan to complete the C port of RADE V2 to beta level and encourage the first
over-the-air real-time tests. This will be a beta version while ML re-training and algorithm tweaks proceed in parallel. This beta release should be considered experimental — re-training may change the waveform at any time, breaking compatibility with earlier beta versions and with the final release. Beta testers should expect incompatible updates at short notice.

The FreeDV project leadership team has agreed on test guidelines that will allow us to collect high quality test feedback, and methodically investigate any issues. The verification guidelines will gate any feedback by making sure application developers have first verified their integration of RADE V2 – so we are not chasing application bugs unrelated to RADE V2.

Other activities this month included progress on an article for QST, and help collating answers for a new campaign promoting RADE.