Operation
Model 8642A/B
RF Frequency Sweep (cont'd)
5) Calculate the automatically selected X-axis steps for a desired sweep time setting.
Automatically selected number of X-axis steps equals the minimum of:
1023
or
Sweep Time (in ms)
1 ms
Note: The X-Axis Output changes in steps while frequency changes in a phase continuous
manner.
6) Calculate the required sweep time to select a desired number of X-axis steps. The
desired number of steps must be less than or equal to 1023.
Sweep time (in ms) is equal to:
Desired Number of Steps X 1 ms
Note: The X-Axis Output changes in steps while frequency changes in a phase continuous
manner.
Example for Calculation #3 (Phase Continuous Frequency Sweep)
Set the instrument to a known state by selecting [ INSTR PRESET I .
Set a Phase Continuous Frequency Sweep from 250.2 to 250.3 MHz at the minimum
possible sweep time. (This sweep will occur in divide band 7 with divide number 4.)
Minimum sweep time is equal to the maximum of 5 ms or:
Minimum Sweep Time = | 250200000 - 2503000001 X 4 X 0.002 ms = 800 ms
Since 800 ms is greater than 5 ms, 800 ms is the minimum sweep time. Also, since 800
ms is an integer number of ms, this value can be set directly.
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