IT ALL BEGAN about half a hour ago when 1680 AM was turned off for the day. For awhile there was ordinary far away background noise, but suddenly, with a noticeable “on” burst I was hearing a hash noise, just like digital stream noise, with steady buzz over-laid by bursts and dips. The other day, in a different location, I reported on something similar coming on the car radio at 1680.
Thinking I could see a signal level or get an idea if the noise went up above the AM band I clicked on the Alinco communications radio, and when I got up to 1700kHz I heard a very pleasant violin recital on a frequency normally belonging to a far away sports station. Trying two other radios, I clearly heard sports on 1700kHz.
At almost 9 PM I got an idea and tried 850kHz and there was the violin music, the station there is on late during May and would sign off at 9 PM. I had been hearing their 2nd harmonic.
But it is still strange, because the other two radios could not hear the violin music, and were only able to receive the far away sports.
One last note, the 2nd harmonic from 850kHz is usually a suppressed buzz and the audio tends to be very suppressed.
Odd stuff. The computer-like noise must have stopped.