Specifications

12
6. When the calibration is complete, activate flat-
ness correction.
[PRIOR MENU]
{FLATNESS ON}
7. Verify the constant power level at the test port
by using the 437B to measure the test port power
at CW frequencies. As the power is manually meas-
ured, the user must enter each test frequency on
the 437B so that the correct calibration factor will
be used.
8. The analyzer will automatically store the correc-
tion table into register 1 of the source.
9. Remove the power sensor. Connect AUT and
apply bias, if necessary.
Once the flatness calibration has been completed
the user may choose to reduce the measurement
frequency span at any time without invalidating
the flatness correction.
Absolute output power
After port 1 has been calibrated for a constant
input power, the 8510C can be used to display
absolute power (in dBm or mW) versus frequency.
1. Perform a power flatness correction over the
desired frequency range and power level (as previ-
ously described).
2. Set up channel 1 for the desired frequency
range, number of points and step sweep mode.
3. Set the source power at a value appropriate for
the device under test. This step is necessary to get
a correct reading of absolute power. Connect a
thru and perform a receiver calibration to remove
the frequency response errors of the port 2 path in
the measurement. Be sure to include any attenua-
tors or adapters which are part of the measurement.
[CAL]
{RECEIVER CAL}
{INPUT PWR}
{OUTPUT PWR}
{SAVE RCVR CAL}
If several THRU’s have been defined in the calibra-
tion kit, a further menu appears after {OUTPUT
PWR} is selected to allow selection of the appropri-
ate standard.
A flat line should be displayed at the correct power
level.
4. Connect the AUT and apply bias, if necessary.
5. When Receiver Cal is turned on, parameter
User 1 a1 displays input power (P
in
) in dBm and
User 2 b2 displays output power (P
out
).
PARAMETER [MENU]
{USER 1 a1}
{USER 2 b2}
Figure 10. Test port power before and after a power meter
calibration
Figure 11. Absolute output power measurement