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Offset Atlas MW: 9 kHz Raster - ready to download
Hi - now the "Medium Wave Offset Atlas" with 9kHz channels has been finished and can be dowloaded for free at:
Like his 10kHz brother, it contains the screenshots of spectrograms of each channel over 24 hours, reception in Germany, on January 19, 2021, within a window of 50 Hz. Some odd channels had been also included. To nail the actual offsets in but a millihertz-range, I used the new FDM-S3 with OXCO/GNSS control guarenteeing accurate and stable frequencies.
From a recording just two days later, I also added some Frequency Standard and Time Signal stations plus all longwave broadcasting channels (Mongolia!) in just the same manner.
The purpose of this now rather complete "Atlas" is to have an overlook about what can be generally received at my location and with a professional omnidirectional vertical dipole antenna; and to exactly measure offsets. With a system gain of about 70dB, compared to a 10kHz wide channel, stations from Hawaii, Laos, Swaziland etc. had already been identified, e.g. by their times for sign on or sign off plus fade-in and fade-out. Additonally specific offsets further enhance the fun - see Offset List of the indispensable MWLIST.
I now hope to finish a more general article about "How to do", featuring also some brand new software for this purpose.
73 Nils, DK8OK