Multiple listeners have copied USB ALE on 30000.03 kHz USB (dial/window frequency). It's always soundings by EN10, a known military call sign used by the National Guard.
This is not the first time I have noticed ALE above 30 MHz, though it's the first time I actually got a decode on it.
Be warned that the frequency also has a signal consisting of a continuous stream of beeps, with alternating pulse lengths measured at 0.1 and 0.15 seconds. Nothing about this is known, except that it strongly appears to be a propagated signal as opposed to, say, a nearby radiolocation beacon.
Yesterday's activity is shown in a YouTube video on this column's channel.
