Keysight 8990B Service Manual page 29

3 Offset the signal generator's power by the gain of the power amplifier. On the
4 Zero and calibrate the standard and incident sensors on channels A and B
5 Set the frequency of the signal generator to 50 MHz and the power level to
6 Set the frequency of the power meter's channels A and B to the same
7 Measure the standard power (P
8 Repeat steps 4 to 6 for other frequencies with the same power level.
9 Turn off the RF output of the signal generator.
10 Remove the standard sensor from the test port.
11 Replace it with the 8990B and N1923A/N1924A power sensor, which is the
12 Zero and calibrate the DUT.
13 Measure and record the power readings of channels A and B for the current
14 Turn off the RF output of the signal generator.
15 Compute the accuracy error of the DUT for each frequency being measured at
16 Repeat steps 13 to 15 for other frequencies with the same power level.
Keysight 8990B Service Guide
signal generator, press Amplitude > More (1 of 2) > Ampl Offset. Gain is
entered as a positive number while loss is entered as a negative number.
For example, if the amplifier gain is 28 dB, enter +28 as the amplitude offset.
respectively.
+10dBm. Turn on the RF output.
frequency as the signal source.
(P ) of channel B. Compute and record the coupling factor (P
INC1
channels for the current frequency, based on the following equation:
P dB = P
( )
–
cpl STD
device-under-test (DUT).
frequency and power level, as P
N1912A's channel B).
the same power level, using the following equations:
Accuracy error (dB)
Accuracy error (%)
Performance Verification and Adjustments
) of channel A and the incident power
STD
P
INC1
(from the PC) and P
DUT
= P P +
(
–
DUT INC2
P
× - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
= 100 anti log
(from the
INC2
P
)
cpl
( P + P )
–
DUT INC2 cpl
10
1
) of these
cpl
1
–
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