Cascading Signal Generators

This is a handy trick to make a AM signal with a time-variant envelope frequency by cascading signal generators. The Agilent 33220A signal generator, among its many functions, can make frequency sweeps OR modulated signals. It cannot do both.

Cascading Trick

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The solution is simple: Make a frequency sweep on  a Generator A, feed the sweep to the BNC external modulation input of Generator B, use Generator B to add the desired carrier frequency and set it to external modulation. The output of Generator B will be a AM signal with a time-variant envelope frequency .
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