Fluke 9640A Series, Инструкция по эксплуатации

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Calibration
Performance Test
5
5-31
Note
The 6 dB attenuator is used to minimize mismatch errors. In some cases,
additional attenuation may be required to satisfy alternative measuring
receiver maximum input limitations.
Note
Unwanted interference from signals at 10MHz due to the frequency
reference outputs of equipment operating in the vicinity of the test setup or
the equipment used during the tests can cause erroneous results. In order to
avoid such problems, it is recommended that a small offset (50kHz) is
added to the listed nominal test frequency.
2. On the UUT enable the REF FREQUENCY OUTPUT at 10 MHz and set the UUT as
follows:
Frequency 10 MHz
Level +16 dBm
Output
OPER
3. 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.
4. At each attenuation level listed in Table 5-16, allow the measuring receiver reading
to stabilize, ensuring the indicated value is within the relevant tolerance.
5. Return the UUT attenuation to 0 dB (+16 dBm).
6. Repeat steps 2 through 6 at the attenuation levels shown in Table 5-16 for
frequencies of 50 and 100 MHz.
7. Set the UUT to
STBY
.
Table 5-16. Attenuation Accuracy (50
Ω
)
Nominal
Attenuation
Absolute Output
Level
Specification
0 dB +16 dBm Reference
-13 dB +3 dBm ±0.035 dB
-23 dB -7 dBm ±0.035 dB
-33 dB -17 dBm ±0.035 dB
-43 dB -27 dBm ±0.04 dB
-53 dB -37 dBm ±0.04 dB
-63 dB -47 dBm ±0.04 dB
-73 dB -57 dBm ±0.1 dB
-82 dB -66 dBm ±0.1 dB
-91 dB -75 dBm ±0.1 dB
-100 dB -84 dBm ±0.1 dB