Error in spectrum window

Guest · Post by **Guest** » Mon Jan 21, 2008 9:07 pm

When doing spectrum analyze on a sine wave I get different level depending on the setting on the bandwith. Very strange. I'm talking about 5-10% or so.

Is this a known problem?

I'm running the latest (I think) Picoscope6.

Thanks in advance!

/Peter

PeterF · Post by **PeterF** » Tue Jan 22, 2008 11:28 am

Hi,
There will be some variation when the bandwidth is changed. The most accurate readings will be when the measured frequency is just below the upper range of measurement (a full scale reading). At higher bandwidth settings, when the peak is only a fraction of the full bandwidth, accuracy will suffer. The number of frequency bins selected will also have an effect.
PeterF.

Audioguy · Post by **Audioguy** » Wed Feb 06, 2008 11:12 am

Thanks!

I was aware of the relationsship between FFT points and frequency of sampling.. must have had an off day.

/Peter