Fluke 9640A Series, Instruction Manual

Page: 213 / 324

Calibration
Performance Test
5
5-23
Note
The diode-based power sensor may exhibit frequency dependent linearity
errors, and additional corrections for these errors must also be applied.
21. Allow the power meter reading to settle. Record the measured level in dBm as P
2
for
use later in this procedure.
Note
The power meter autorange boundary may coincide with a measurement
point. To avoid unwanted power meter autoranging, manually lock the
power meter range once the 100kHz reading is obtained and maintain the
power meter range lock for all subsequent frequencies at this amplitude.
22. Set the UUT frequency to the first test frequency listed in Table 5-13 MHz.
23. Enter the measurement frequency into the power meter and allow the power meter
reading to settle. Record the measured level in dBm as
P
3
. Calculate the UUT output
P
out
= P
1
+ ( P
3
– P
2
).
24. Check that the value of P
out
is within the tolerance shown in Table 5-13.
Note
The insertion loss of the 50 Ω Type-N female-to-female adapter must be
taken into account at each measurement frequency.
25. Set the UUT to the next frequency point listed at this amplitude in Table 5-13, and
repeat steps 14 through 15.
26. Set the UUT to 100kHz at the next amplitude listed in Table 5-13, and repeat steps 11
through 16. When the test amplitude is -37dBm at each frequency record the value of
P
out
at -37dBm as P
-37
, and when the test amplitude is -47dBm at each frequency
record the value of P
out
at -47dBm as P
-47
. These values will be used later in this
procedure.
27. Set the UUT output to
STBY
.