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Can't measure above 5000 Hz octave band in LMS Testlab signature.

Creator
Creator

Recently started using the ANSI octave add-in in signature.  I set the bandwidth really high, around 20,000 Hz.  

 

But the realtime octave is always only 5000 Hz.  

 

What am I doing wrong?  How do I get higher than 5000 Hz octave band?

3 REPLIES

Re: Can't measure above 5000 Hz octave band in LMS Testlab signature.

Siemens Experimenter Siemens Experimenter
Siemens Experimenter

Hello Merric, 

 

You probably need to raise the default upper center frequency. 

 

In the Measure screen, got to the Acquisition tab (F5) and then the RTO tab (F10). 

 

Increase the Upper center frequency from 5000 Hz to whatever you need (for example 16000Hz). 

 

oct.jpg

 

Let me know if that works for you, 

 

Jacklyn

 

 

Re: Can't measure above 5000 Hz octave band in LMS Testlab signature.

Creator
Creator
That worked! Thanks!

Re: Can't measure above 5000 Hz octave band in LMS Testlab signature.

Siemens Phenom Siemens Phenom
Siemens Phenom

In addition to Jacklyn's suggestion, also go to either Acquisition Setup or Measure, F5 Acquisitionb and increase the fixed sampling Bandwidth.  The two fields are linked and the RTO Upper Frequency cannot go above the Fixed Sampling bandwidth.  The main reason is that the throughput data will have that bandwidth and we cannot calculate octave bands above it.