Note that the red trace continues after Pyongyang fades out. At the time that the green frequency trace jumps down about 3-5Hz or more another, unknown station has faded in, then switches off at 04.00. Not seen on all dates.
Pyongyang December 2009
November 2020 I see Google has drastically reduced resolution in their site conversion. All pictures are available. I will replace sometime.
Pyongyang=Nov09.png
Pyongyang=Dec09.png
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