[Spooks] UNID "One Beep, Two Beeps" signal at 4508 kHz

[Curt Rowlett]

I captured a video of an unusual transmission that I've named "One Beep,
Two Beeps" for rather obvious reasons:

https://youtu.be/6pQOSnu4aTQ

This was recorded on Tuesday, November 28th, at approximately 1640 UTC,
using the Utwente WebSDR. Since that time, I have been checking that
frequency several times a day and have never heard the signal again. I was
first notified of its presence by another shortwave listener, who has also
been monitoring the frequency, as well. He has not reported any repeat,
either.

I have no idea what this is, or if it is anything other than just a one-off
anomaly.

Regards,

Curt / W9SPY
Seattle, Washington USA