HP 8753E manual Power Meter Calibration, Primary Applications, Calibrated Power Level

Power Meter Calibration

‘I& p~~~~~~;‘:~.~ softkey with the come-$ion menu, leads to a series of menus

associated with power meter calibration.

An HP-IB-compatible power meter can monitor and correct RF source power to achieve leveled power at the test port. During a power meter calibration, the power meter samples the power at each measurement point across the frequency band of interest. The analyzer then constructs

a correction data table to correct the power output of the internal source. The correction table

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may be saved in an instrument state register with the $&E key.

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The correction table may be updated on each sweep (in a leveling application) or during an initial single sweep. In the sample-and-sweep mode the power meter is not needed for subsequent sweeps, The correction table may be read or modified through HP-IB.

Primary Applications

nwhen you are testing a system with significant frequency response errors ( For example, a coupler with significant roll-off, or a long cable with a significant amount of loss.)

nwhen you are measuring devices that are very sensitive to actual input power for proper operation

nwhen you require a reference for receiver power calibration

Calibrated Power Level

By setting the analyzer calibrated power to the desired value at the power meter, this power level will be maintained at that port during the entire sweep. First set the source power so that

the power at the test device is approximately correct. This reduces residual power errors when

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only one reading is taken. Refer to ~~~~~ :IE@?Z#@~ softkey description in Chapter 9, “Key Definitions.” When power meter calibration is on, the annotation PC is displayed. This indicates that the source power is being updated during the sweep. Calibrated power level becomes the active entry if any of the following softkeys are pressed:

.I%#EJii (if power meter cal is on)

Regardless of the measurement application, the analyzer’s source can only supply corrected power within the selected power range. If power outside this range is requested, the annotation will change to PC?.

Compatible Sweep Types

Power meter calibration may be used in linear, log, list, CW, and power sweep modes. In power sweep, the power at each point is the true power at the power meter, not the power at the analyzer’s source output.

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