Fluke 9640A Series, Instruction Manual

Page: 250 / 324

9640A
Instruction Manual
5-60
Alternatively, the UUT units selection may be changed to V rms to display
targets and adjust output values directly in rms voltage. Press the
Units
key
and select the required units.
Note
Measurements made on the 5790A 2.2 mV range (at levels below -42 dBm)
require correction for the 2.2 mV range linearity error.
8. Press
Next
Target .
9. Repeat steps 7 and 8 for all points requiring the use of the AC Measurement Standard
(the UUT text box will indicate
Use Precision AC Voltmeter
)
. Use Power Meter
.
Set the UUT to
STBY
.
10. Disconnect the AC Measurement Standard and feedthrough termination from the
Leveling Head. Connect the UUT 75
Ω
Leveling Head to the input of the 75
Ω
power
sensor using a Type-N female-to-female adapter. See Figure 5-10 for equipment
connections.
Note
The insertion loss of the 75
Ω
Type-N female-to-female adapter must be
taken into account at each adjustment frequency.
11. Set the power meter for 0.001 dB resolution.
Note
The following steps facilitate the high and mid-level flatness adjustment of
the 75
Ω
Leveling Head using a power meter and sensor.
12. Set the UUT to
OPER
.
13. Enter the measurement frequency corresponding to each
Target
into the power meter
to enable cal factor (frequency) correction.
Note
The recommended power meter has power sensor calibration factors stored
internally in the sensor. Setting the input frequency in the power meter
automatically selects the appropriate cal factor for the measurement.
However, the power sensor may also be accompanied by a table of
calibration factors which must be applied externally.
Note
The power meter autorange boundary may coincide with a measurement
point. To avoid unwanted power meter autoranging during the adjustment
process, manually lock the power meter range when the UUT indicates the
current adjustment point is a Transfer Point and maintain the power meter
range lock for all frequencies at that amplitude. When the sequence reaches
the next Transfer Point allow the power meter to autorange and then
manually lock the power meter range again, continuing in this fashion for
all points requiring use of the power meter.
14. Using the blue arrow keys and rotary knob, edit the UUT
Actual
output until the
power meter indicates the
Target
value stated. Press
Accept Target
.
15. Press Next Target .
16. Repeat steps 13 through 15 for all points requiring the use of the power meter and
sensor (the UUT text box will indicate
Use Power Meter
). Set the UUT to
STBY
.