Last night I started SpecLab to plot 10-72 kHz

Here is the result until 0800 local ( = 0700 ut)
http://dx.3sdesign.de/temp/Spectr-110126-0800_10-72kHz.jpg

The same but zooomed
http://dx.3sdesign.de/temp/Spectr-110126-0800_14-28kHz.jpg

The 20kHz line seems to be a product of SpecLab using Perseus

Perseus alone doesn't show the 20kHz and neither does Winradio



Jurgen Bartels  Suellwarden, N. Germany
hor. Antennas: 11-ele 45-87MHz 13-ele Band-III, 48-ele UHF, FM: 15.11 
TV: Winradio G305 / Fly2000 + video noise filter & variable IF BW
FM: Downconverter + Perseus + Speclab as WFM demod.
MW: staggered 300m Beverage 320°,  30 x 4m EWE 320°, Winradio & Perseus
http://dx.3sdesign.de/tv_offset_list.htm
http://dx.3sdesign.de/station_list.htm

http://fewo.3sdesign.de  - Vacation home: DX right at the Northsea coast