Of the 4 SAQ Grimeton broadcasts I was able to listen to in 2023 this was by far the best reception with a clear CW signal, S4. A week later I received their e-QSL!
SAQ Grimeton is a former wireless telegraph station in Sweden. It generates radio signals using an AC generator (called an alternator) designed by the Swedish engineer Alexanderson. This technology was used prior to the development of vacuum tube oscillators. You can learn more about the history of this station and its planned transmissions on the website of the Alexander assocation.