[hpsdr] Spurs!!!!! Hermes! !!!!

[Erik van Maanen]

24.576MHz, yes -83 dBm
36.88MHz, at 36,864 -84 dBm
49.1MHz, at 49,152 -82 dBm
49.9MHz, no
52.5MHz, yes -110 dBm

First TAPR version of hermes FW 2.9
These are narrowband low level carriers that were always there, never paid much attention to improve shielding etc.
This seems not to be a firmware issue.

I havent seen the 30kHz bumps you are speaking of but I experienced similar things with a switched mode power supply, the touchpad of my lenovo laptop and a led tv.
Now I use a decent powersupply for hermes and put ferrite around the cables of the laptop power supply and most of it is gone.
Have a look for an external cause leaking trough the cabling of hermes.

73  Erik PA3DES


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