I have been hearing this strange signal for a week since i discovered it, the beeping pattern is changed every 12/24 hours, and specialy today the signal was quite strong. Does somebody knows what could this be ?, could this considered a polytone transmission ?
https://www.youtube.com/watch?v=LDwOyrbaGoo&feature=youtu.be
https://www.youtube.com/watch?v=LDwOyrbaGoo&feature=youtu.be