[Lf] [Fwd: LF: DCF39 in the US - first analysis]

[Andre' Kesteloot]

"'Geri' Kinzel, DK8KW" wrote:

> Hello friends,
>
> Dick,  WA3USG had send me a file of a recording he has made in the US and
> what he thinks might be DCF39,
>
> I have made a first very preliminary analysis tonight. The file contains a
> carrier on 700 Hz which can clearly be seen on Spectrogram 5.1.6 ( and also
> can clearly be heard through the noise.
>
> I found the following inconistencies in that carrier:
>
> 11595 ms - 12089 ms     (length 496 ms)
> 25605 ms - 26289 ms             (length 684 ms)
>
> time in between 13516 ms.
>
> In the second half of the file the noise was too strong and the AGC of
> Dick's receiver pulled the signal down, so that reading here were not that
> clear.
>
> My first very cautious analysis would be to assume, that those
> inconsistencies in the carrier might be the data bursts of DCF39. Data of
> these bursts vary, the recording I had on hand showed values for the length
> of the data burst between 876 ms and 883 ms and the time in between two
> bursts 11488 to 13500 ms.
>
> What I need, if possible, is a longer recording (5 to 10 minutes) with AGC
> off. Additionally, it would help to have a similar recording of the data
> frequency of the FSK signal on 139.170 kHz.
>
> Best 73
>
> Geri, DK8KW (W1KW)