Fluke 9640A Series, Инструкция по эксплуатации, Страница: 231 / 324

Calibration
Performance Test
5
5-41
Making these precision low-level measurements requires appropriate
choice of measuring receiver settings to provide adequate linearity, noise
floor, and reading repeatability throughout the amplitude range required.
For any given frequency the measuring receiver the settings must be
maintained for all amplitudes at that frequency after establishing the
reference point. In particular, receiver attenuator, reference level, and
resolution bandwidth settings must not change.
20. On the UUT enable the REF FREQUENCY OUTPUT a 10 MHz and set the UUT as
follows:
Frequency 100 kHz
Level -43 dBm
Output
OPER
21. Allow the measuring receiver to tune the input signal, and then set the controls to
measure RF level, relative (dB) to the current input level.
22. Without changing any measuring receiver settings, set the UUT to the next amplitude
for this frequency listed in Table 5-20. Allow the measuring receiver reading to
stabilize and record the reading as P
rel
. (Note that P
rel
will be a negative number in
dB).
23. Calculate the UUT output P
out
= P
-43
+ P
rel
. Check that the value of P
out
is within
the tolerance shown in part A of Table 5-20.
24. Repeat steps 22 and 23 for each amplitude listed for this frequency in part A of Table
5-20.
25. Return the UUT output to -43dBm, set the UUT frequency to the next frequency
listed in part A of Table 5-20, and repeat steps 21 through 24.
26. Set the UUT to 100 kHz at -33 dbM. Repeat steps 21 through 25 for the points listed
in part B of Table 5-20 using the calculation P
out
= P
-33
+ P
rel
in step 23.
27. Set the UUT to
STBY
.