Re: LF: 2200m Plots of the whole Band

[Markus Vester <markusvester@aol.com>]

Those gaps occur at +-30 Hz from each 200 Hz multiple, i.e. 137.77, 137.63, 137.57, 137.43, 137.37 kHz etc. They are only a few Hz wide and apparently caused by symmetries in the 200 baud, 2x170 Hz shift FSK modulation.

 

There are usually four hyper-active periods per day with very dense telegrams, the longest one occurring every evening around 21:20 to 22:50 UT. 

 

Hartmut as you are fairly close to the DCF39 site, I would have expected even stronger sidebands in your spectrograms. Were these from your K9AY antenna pointing away from Burg?

 

Best regards,

Markus (DF6NM)

 

-----Ursprüngliche Mitteilung----- 
Von: Hartmut Wolff <h-wolff@gmx.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Fr, 8 Jan 2016 7:46 pm
Betreff: LF: 2200m Plots of the whole Band

Here are plots of the whole 2200m Band from the past 2 Nights (about 1.5MB): 
 
https://dl.dropboxusercontent.com/u/50178231/LF/w136900_2016-01-07.JPG 
 
https://dl.dropboxusercontent.com/u/50178231/LF/w136900_2016-01-08.JPG 
 
My be its useful to find the gaps of the DCF39 Sideband for your  
transmissions. 
 
73 
Hartmut