... the strong noise bands were caused by Luxembourg effect (ionospheric crossmodulation) from a strong LF or MF broadcasting
transmitter onto the DCF39 carrier. When the "heater" is modulated by music, the spectrum often shows distinct bands related to the
tones of the musical scale. Attached is a grabber snapshot just after 2:10, with DF colours rotated to bluegreen. The band near
137.78 kHz is clearly visible.
Despite some distant QRN, very good signals from XKO and WD2XKO were visible through most of the night, with the last "J" coming
through as late as 9:15.
Kind regards
Markus, DF6NM
----- Original Message -----
From: ""Jean-Pierre Méré (F1AFJ)"" <[email protected]>
To: <[email protected]>
Sent: Tuesday, January 06, 2009 10:44 AM
Subject: Re: LF: Noise
Hello Lubos and LF,
Very interesting this observation, I also thought me of local QRM !
Very great activity on 137 Khz, (the grabber of Laurence in China made in true
"catch"! )
73 qro JeanPierre f1afj
Lubos OK2BVG a écrit :
Jean-Pierre, LF!
I had thought, that it was local noise, but then I saw it on your grabber as
well. This noise started 02:10 and stoped 03:05UT.
73, Lubos, OK2BVG
DCF39_ICM_090106_0210-0213.jpg
Description: JPEG image
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