On 7 April 2011 18:33, wolf_dl4yhf <[email protected]> wrote:

Hi Roger,

Guess the burst originates from a periodic signal (maybe something rich in harmonics), and one of the harmonics is closer to one of the frequency ranges than the other. Or.. the two bands are fed from two different sources - one before, and the other after the noise blanker, or clipper ? You can quickly check that in the 'circuit' window. But if you say it's just the split screen mode, then the two frequency ranges are indeed fed from the same FFT.

All the best,
 Wolf .


Am 07.04.2011 18:09, schrieb Roger Lapthorn:

Help...

After lunch today my wife turned on the washing machine and the tumble drier and for two periods there was a burst of interference visible on the lower split screen as vertical noise stripes. What I don't understand is why I don't see these also on the upper trace around 8.976kHz too when the settings are the same.  I have a SL filter selected but it is centred around 8.970kHz with 400Hz width and slopes so this cannot explain this. Surely the noise bursts should appear in both parts of the screen?

Can someone who understands Spectrum Lab explain this please?

73s
Roger G3XBM