Agilent Technologies 8753ET User Manual page 58

Making Measurements
Measuring Electrical Length and Phase Distortion
3. Substitute a thru for the device and perform a response calibration by pressing:
Cal CALIBRATE MENU
4. Reconnect your test device.
5. To better view the measurement trace, press:
Scale Ref AUTO SCALE
Notice that in Figure 1-34
span. Other filters may require a wider frequency span to see the effects of phase shift.
The linearly changing phase is due to the device's electrical length. You can measure this changing
phase by adding electrical length (electrical delay) to compensate for it.
Figure 1-34 Linearly Changing Phase
6. To place a marker at the center of the band, press
value from the front panel keypad.
7. To activate the electrical delay function, press
This function calculates and adds in the appropriate electrical delay by taking a 10% span about the
marker, measuring the , and computing the delay as the negative of
 /frequency.
Alternatively, press
the electrical length until you achieve the best flat line, as shown in
1-44
RESPONSE
the SAW filter under test has considerable phase shift within only a 2 MHz
ELECTRICAL DELAY
Scale Ref
THRU
and turn the front panel knob, or enter a
Marker
Marker Fctn MARKERDELAY
and turn the front panel knob to increase
Figure
.
1-35.