Figure 5-49 RESONANCE MODE. Wayne Kerr 3260B

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Advanced Operation

For simple components, where the above models are valid, the series or parallel frequency obtained will also correspond to the minimum or maximum impedance point. The results may not be valid for more complex components, especially those exhibiting more than one resonance.

Before initiating a resonance search, enter values for the Start and Stop frequencies corresponding to the range in which resonance is expected to occur. The search process will complete more quickly if close limits are entered. The search will be performed at the AC test level specified in IMPEDANCE MODE, but other test parameters will be selected automatically and need not be specified.

Start the search by pressing the Find Series or Find Parallel soft key. If a resonance is found, the results will appear after a few seconds, as shown in Figure 5-50. With the Find Series or

Find Parallel label highlighted, a further search may be initiated by pressing the Trigger key.

Alternatively, press the soft key again.

If the resonance lies outside the frequency range of the analyzer, it is possible to use an extrapolated search, but the results will be at a reduced accuracy. If no resonance is detected within the specified frequency limits, Figure 5-51 will be displayed and must be acknowledged with either the Yes or No soft key. Answering Yes will cause the analyzer to look for a resonance at frequencies up to 2:1 beyond the limits. For best accuracy, always adjust the limits and repeat if this is possible. Accuracy of extrapolated results is undefined, as it is not possible to verify the validity of the circuit model. If no resonance is detected, or if the No soft key was pressed, the analyzer will report Resonance not found.

Figure 5-49 RESONANCE MODE Figure 5-50 RESONANCE MODE Results

Figure 5-50 shows the result of a series resonant frequency search on a 10µF capacitor with the bandwidth search limits set to 100Hz and 1MHz.

Figure 5-51 Resonance Not Found Message