Measuring Relative Frequency; Relative Frequency Example - Keysight 53147A Operating And Programming Manual

Measuring Relative Frequency

You can measure the difference in frequency from one measurement to another
(frequency drift) or between two separate input signals using the Relative
Frequency function.

Relative Frequency Example

Press the Rel Freq key. The Shift annunciator activates when you press the Shift
key. When you press the Rel Freq key, the Rel Freq annunciator in the upper-left
corner of the display activates. At the same time, the Counter saves the frequency
measurement it was displaying at the time you pressed the Rel Freq key, and it
computes and displays the difference between the stored measurement and all
subsequent measurements until the relative frequency function is deactivated.
You can also use the Relative Frequency function to measure the difference
between two different signals. To do this, activate the Relative Frequency
function, as described in the previous paragraph, disconnect the cable supplying
the signal to the input connector, and then connect the second signal to the same
input connector. The value displayed when the Counter acquires the second
signal is the frequency difference between the two signals.
Keysight 53147A/148A/149A Operating and Programming Guide
Operating Your Instrument 2
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