Chris, 

You should not need to use the 's' meter on HDSDR when taking 
relative readings. The (wideband) waterfall display is already in 
decibels - just place the cursor at the position you want to measure. 
If that doesn't work, go to Options/Visualisation/Informations on 
Mouse position. For noise readings I would increase the averaging 
(Avg) function to perhaps 16 or more to get a flattish line.

As a guide, I find that DCF38 is typically 63dB above daytime noise. 
You are a little further away from DCF, so you should get a slightly 
lower figure.

Mike, G3XDV
==========

 
> I'll  cal  the  HDSDR S meter with my sig gen, and get some meaningful
> figures,  but it may be over the weekend, got a busy week on here,
> thanks Jim.
> 
> > And also, by how many dB does the nighttime background level exceed
> > the midday level?
> 
> > Jim, K8RZ
> 
> 
> 
> 
> 
> 
> 
> -- 
> Best regards,
>  Chris  2E0ILY                          mailto:[email protected]
> 
> 
> 
> 
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