Atek HP 8753D, User Manual, Page: 79 / 677

3. Substitute a thru for the device and perform a response calibration by pressing:
4
CAL
5
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CALIBRATE MENU
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RESPONSE
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THRU
4. Reconnect your test device .
5. T o better view the measurement trace , press:
4 SCALE REF 5
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AUTO SCALE
Notice that in Figure 2-29 the SA W lter under test has considerable phase shift within only
a 2 MHz span. Other lters may require a wider frequency span to see the eects of phase
shift.
The linearly changing phase is due to the device's electrical length. Y ou can measure this
changing phase by adding electrical length (electrical delay) to compensate for it.
Figure 2-29. Linearly Changing Phase
6. T o place a marker at the center of the band, press:
4 MARKER 5 and turn the front panel knob or enter a value from the front panel keypad.
7. T o activate the electrical delay function, press:
4 MARKER F CTN 5
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MARKER ! DELAY
This function calculates and adds in the appropriate electrical delay by taking a 610%
span about the marker , measuring the 1 , and computing the delay as the negative of
1 /1frequency .
Making Measurements 2-31