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How to find a frequency response??

How to find a frequency response of the analog Notch filter (f0=200kHz) using a digital oscilloscope and an arb generator in LabVIEW? The SWEEP method or the WhiteNoise/FFT? What are frequency limits of each method? The best solution is to have a network analyzer, but what to do without it??
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The main differences between the two techniques is that the "white noise" technique is faster, but the accuracy of your results is dependent upon the accuracy of the white noise generator. The sweep technique is slower, but you can compensate in nonlinearities of the signal generator output. Also with the sweep method you might not need an arb, a good sinewave generator might work.

The answer of which to use depends on how fast the test needs to run, and the accuracy you need.


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Mike: thank you for your answer. I wonder how could be the accuracy of the "white noise" technique if I will use simple 20MHz generator and the Tektronics TDS 340 oscilloscope 500MS/s. I am just working on the sweep programm in LabView, but I am curious: the digital processing seems to be simpler?
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