Frequency response test duration

I’m using the QA402 analyzer, with software version 1.154

I’m doing Frequency response tests, and I would like to know if there is a way to control the duration of the frequency sweep.
I mean, if it is possible to set the time (or number of cycles) the generator remains on each frequency.
Or to set the frequency increment rate, to make it slower, and perform a longer test.

Thank you.

Hi @LeoSandler, the duration of the sweep is largely set by the FFT size. So, a smaller FFT will consider fewer cycles in computing the average signal level, while a larger FFT will consider more cycles in computing the average signal level. Generally, as you reduce the FFT size, it’ll be harder to see harmonics. But for frequency response, the larger FFT isn’t really important.

So, give it a try and run the FR with small and larger FFT and put it all on the same graph, and then zoom in and you can see whatever errors might crop up due to FFT selection size.

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Hi Matt,

I tried your suggestion, and it worked.
In addition, I found it possible to configure the frequency and amplitude sweep parameters through Automatic Tests → Amp Freq Response.

Thank you for your help !