2015-01-31
Interesting interference in the 10 meter amateur band
I had the radio and computer running checking for PSK31 signals at 28.120 MHz, the standard frequency for PSK31 in the 10 meter band. Suddenly I saw lots of carriers 5 Hz apart and very precise. I checked the websdr in twente and saw the same signal. So I tried to make a screengrab of it and it went away. To show up at 27.120 MHz exactly the same and annoying some 27 MHz CB users. I'm not sure what it was, my first guess was over the horizon radar which is 'famous' for interfering on HF amateur bands. Moving 1 MHz down when the HF propagation maximum frequency is dropping is also a sign of something like over the horizon radar.
I had the radio and computer running checking for PSK31 signals at 28.120
MHz, the standard frequency for PSK31 in the 10 meter band. Suddenly I saw
lots of carriers 5 Hz apart and very precise. I checked the websdr in twente
and saw the same signal.
So I tried to make a screengrab of it and it went away. To show up at 27.120
MHz exactly the same and annoying some 27 MHz CB users.
I'm not sure what it was, my first guess was over the horizon radar which
is 'famous' for interfering on HF amateur bands. Moving 1 MHz down when
the HF propagation maximum frequency is dropping is also a sign of something
like over the horizon radar.