Rohde & Schwarz SMB100A - Test Procedures; Reference Frequency

Test Procedures R&S SMB
1407.0806.82 1.8 E-5
Test Procedures
Reference Frequency
Output of Internal Reference
Important: Allow the DUT to warm up for at least 2 hours before the measurement.
Test equipment
- Frequency counter (Table 1-1, item 1)
Test setup  Connect a calibrated frequency counter to the REF OUT output (on
rear panel).
Measurement  Measure the frequency.
 The frequency deviation must not exceed the sum of
deviations resulting from the frequency error in the rated
temperature range and from aging.
Input for External Reference
Test equipment - Frequency counter (Table 1-1, item 1)
- Signal generator (Table 1-1, item 5)
Test method The external reference input frequency of the DUT is varied according
to the data sheet and the RF output signal frequency is controlled with
a frequency counter to follow this variation.
Preparation of measurement  Connect the signal generator RF output to the REF IN input for
the external reference (on rear panel) of the DUT. Connect a
calibrated frequency counter to the RF output. Synchronize the
signal generator and the frequency counter.
 Setting on DUT:
- RF on
- Level: 0 dBm (suitable level for the frequency counter)
- Frequency: 1 GHz
- Setup Reference Oscillator  Source: External
 Setting on signal generator:
- RF on
- Level: 0 dBm
Measurement  Set the signal generator frequency to 9.99997 MHz and
10.0003 MHz. Measure the output frequency of the DUT.
Signal generator frequency 9.99997 MHz 10.0003 MHz
DUT frequency 999.997 MHz 1000.03 MHz
There must be no relative frequency error and no error
message in the display of the DUT.