Sent out instrument for Calibration recently and came back with all spec tolerances within test limits per Agilent spec sheet.
*Few notes:*
Some of the test specs Frequency Response preamp off: Reads 0.67dB
Input reference level of 10dB reads 10.45dB. (within spec of +/- 0.5dB)
Actual Measurement:
Input path to the Rf chain from synthesizer -5dbm to -2dBM (path of measurment where spectrum analyzer used)
Usual readings/measurement for DUT at 64MHz: 5.4dB, 360MHz: 17dB, 295MHz: -13.5dB, 280MHz: 17.5, 15Mhz: 4.4dB
After recent drift in Spectrum analyzer measurements (Please note RF internal alignment performed)
64MHz: -6.7dB, 360MHz: 19dB, 295MHz: -12.3dB, 280MHz: 19.2dB, 15MHz: 5dB
We have observed close to 1dB shift in the readings on the spectrum analyzer.
What would cause such an issue? Looking for some help and advice in this regard.
*Few notes:*
Some of the test specs Frequency Response preamp off: Reads 0.67dB
Input reference level of 10dB reads 10.45dB. (within spec of +/- 0.5dB)
Actual Measurement:
Input path to the Rf chain from synthesizer -5dbm to -2dBM (path of measurment where spectrum analyzer used)
Usual readings/measurement for DUT at 64MHz: 5.4dB, 360MHz: 17dB, 295MHz: -13.5dB, 280MHz: 17.5, 15Mhz: 4.4dB
After recent drift in Spectrum analyzer measurements (Please note RF internal alignment performed)
64MHz: -6.7dB, 360MHz: 19dB, 295MHz: -12.3dB, 280MHz: 19.2dB, 15MHz: 5dB
We have observed close to 1dB shift in the readings on the spectrum analyzer.
What would cause such an issue? Looking for some help and advice in this regard.
Our site is shut down during the Chinese New Year Holiday. So we could only do some test with units until Feb 10th.
But, we could still check your results with the datasheet.
The overall amplitude accuracy is +/- 1.5 dB (-50 - 0 dBm signal input, attenuation 20 dB) in N9320B datasheet.
Your normal result is 64MHz: 5.4dB (-5.4 dB??), 360MHz: 17dB, 295MHz: -13.5dB, 280MHz: 17.5, 15Mhz: 4.4dB
N9320B test result is 64MHz: -6.7dB, 360MHz: 19dB, 295MHz: -12.3dB, 280MHz: 19.2dB, 15MHz: 5dB
For the signal smaller than 0 dB, the test results still meet the spec of datasheet. For the signal did not meet spec, please note they are larger than 0 dB which is out of the range.
To further checking this case, we will test it once we are back to office.
Best Regards
Simon