While in an AM QSO with Dave GW4GTE a very strong undulating digital signal landed on top of us. Dave heard it loudly from his location in Europe and as you can see in the video at the link below it was very loud here in the NE corner of the US. Any thoughts on what this might be? It was approximately 18 kHz wide stretching from 21.415 to 21.433 and had a duration of exactly 30 minutes on this particular morning between 15:30 UTC and 16:00 UTC.
http://www.youtube.com/watch?v=K5strfHfiFw&feature=youtu.be
