RUSSIAN MILITARY OFDM OPERATING ON 40METERS
The IARU Monitoring System newsletter reports that the
Russian military have been transmitting on 7000.8 kHz using
OFDM 112 coding. The transmitter generating the unwanted
noise appears to be located near the city of Severomorsk.
But Russia is not alone on the 40 meter band. The IARU also
notes that Chinese Over the Horizon Radar has turned up
several times on 7 MHz in the evening hours. It sometimes
occupies as much as 280 kHz of spectrum and has been heard
up to 7040 kHz using the well known sweep rate of 43.5
sweeps per second.
Needless to say, hams who DX near the low end of 40 meters
would like to see these operations gone from the airwaves.
I think you will find that this signal comes from ZL1THG in New Zealand. If
you use a program like Spectrum Lab you can read the CW on the waterfall,
its way to slow other wise. I am not sure of his purpose, he has done this
on the bottom end of 80m too. It's supposed to be about 100 milli watts.