Making Measurements Using Spectrum Analyzer Mode
Measuring Amplitude Modulation with the Fast Fourier Transform Function
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REF | 424.2 |
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| AT | 20 dB |
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SMPL |
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| NORM*L | ||||
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| % AM |
| 4c.37 | ?6 |
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| AMPTD | |||||
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sn | VB |
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SC | FC |
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| YJ”r’h’ | yqFF | ||||
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| 1 | Of | 2 | ||
FFT | START | 0 | HZ |
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| FFT | STOP | 250 | HZ |
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| #RFS | RW | 30 kHZ |
| “BW 30 ktlZ | “SWP | 800 |
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Figure
Example 2: Use the automatic FFT measurement to look at 60 Hz AM modulation.
1.Connect a signal generator to the spectrum analyzer’s INPUT 75 62. Adjust the signal generator to produce an AM signal with a 60 Hz modulation
‘frequency.
2.Press [FREQUENCY) and set the spectrum analyzer center frequency to the frequency of the modulated input signal. Press (SPAN), 10 IhllHz). Press [FREQUENCY) to keep the signal on the spectrum analyzer display.
2.Press
5 - 9