AnsweredAssumed Answered

N9912A Displaying Impulsive Noise

Question asked by M0JWB on Oct 14, 2010
Latest reply on Oct 21, 2010 by am95405
I am having problems getting this analyser to display Impulsive noise during spectrum measurements using an External antenna fitted to the RF IN port.
We have made comparisons with many other analysers, all of which have no problem displaying any impulsive noise that may be present (vehicle ignition systems, nearby arcing insulators etc). I have performed tests using a domestic hair dryer as a known source of impulse noise and the N9912A has severe problems in displaying this noise as compared to other analysers that we have.
I have tried all of the various settings and I can only get the analyser to display the noise spikes when the RBW is set above 200kHz.
I have noted that when RBW is above 200kHz, the calculations switch from FFT to STEP.
There is no method of manually switching from FFT to STEP without having to increase RBW above 200kHz.
Using such a high RBW defeats our objectives because the noise floor of the instrument is much higher and I am looking for weak noise signals.
The other analysers have no problems using much lower RBW figures

Thanks in advance for any help you may be able to give.

Jim (UK)