Spectrum analysis shows strange carrier

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dexter zero-kelvin at gmx.de
Tue Jul 21 09:53:03 UTC 2009


Hello Dieter.
> In the meantime I did check with my spectrum analyzer. There is
> indeed a signal coming from the BS-11, even if nothing else is
> connected to the BS-11 (no serial connection, no E1). The signal
> starts to be emitted after the firmware download is complete.
>
> I could measure the signal at 942.4 MHz, the level is about -42 dBm
> (cable connection from the spectrum analyzer to TRX0, low-quality
> cable). The signal strength does not depend on the power amplifier
> setting, I wonder where it comes from (some internal oscillator
> working at that frequency ?). The signal is not very strong, so
> it should not cause major trouble (besides disturbing a weak
> signal which might be there from an "official" source if you
> are close to the BS-11).
>   
I think i can confirm that. This was measured during the BS11 startup:

http://root.runningserver.com/pub/startup-phase.png

For me the case is closed, think this behaviour is just normal.

regards,
Philipp





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