Luboš OK2BVG operates the OK0EMW beacon on the frequency 505,060 kHz. Information about the lighthouse can be found on the website http://www.mujweb.cz/zabava/ok2kfj . If you want to test your device on this band, you can listen in the evening.
The beacon transmits a CW signal and also QRSS3. I tried it with the FT-1000MP Mark-V Field, antenna reduced vertical loop to 80m on 8 multi-storey block of flats. You can listen to CW on the recording, which was a strong S5 for me and you can see it in the picture, that the QRSS3 signal was strong at OOO+. Recording in MP3 format .: YOUR :. Send SWL report to Luboš, he will surely be pleased.