[Lowfer] Surprise signal on 185.0 KHz

[WA8EJH]

I was monitoring with dial frequency of 184.0 to see what I might detect 
with Argo.  I didn't see anything after about 30 minutes, so I closed 
Argo.  I had just closed Argo when I was startled by some loud CW.  At 
first I wasn't sure if it was coming from the computer or from the 
receiver.  I switched to Spectran just in time to see the end of the 
transmission.  It was right at 1000 Hz.  I didn't get to visually decode 
the CW, but my ear's memory was that it was dit dah dit dah dah dit dah 
dit without any clear indication of separate letters.  I heard it as R G 
N, but since I was caught by surprise I can't be certain I remembered it 
correctly.  The pattern was repeated a few times in rapid succession and 
then abruptly ended. This was at about 03:00 GMT.

Did I have an auditory hallucination?  Has anyone else ever seen (or 
heard) this?

Larry, WA8EJH