Rohde & Schwarz ZVB 14, Руководство по обслуживанию

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Manual Alignment and Recording Correction Values R&S ZVB
1145.1078.82 2.6 E-4
Aligning the Frequency Accuracy
Test equipment Spectrum analyzer (section "Test Equipment", item 1):
Error <1x10
-9
Test setup: Connect the spectrum analyzer to the 10-MHz reference output at the
rear of the ZVB.
ZVB settings: Select internal reference
MENU : System: Reference Internal
Spectrum analyzer settings: Center frequency: 10 MHz
Span: 200 Hz
Note: Before the following measurement is performed, the ZVB must have
been switched on for at least 30 minutes to give the reference
oscillator time to warm up.
Measurement: Measure the frequency with the spectrum analyzer:
Nominal frequency:
Model without OCXO (Option B4) 10 MHz ± 80 Hz
Model with OCXO (Option B4) 10 MHz ± 1 Hz
Alignment without Option R&S ZVAB-B4:
•
Enter Service Function 2.1.1.6.209.0x000 000
•
Read off the frequency-counter display, e.g. 10.000050 MHz.
•
Change the right-hand segment (corresponding to bit 0 to bit 11) of the data word - e.g. to
000 400 - instead of 000 000 .
•
Read off the frequency counter display again, e.g. 10.000010 MHz.
•
Change the left-hand segment of the data word, until the counter indicates precisely
10.000000 MHz.
Alignment with Option R&S ZVAB-B4:
•
Enter Service Function 2.1.1.6.209.0x 800 000.
•
Read off the frequency-counter display, e.g. 10.000005 MHz.
•
Change the left-hand segment (corresponding to bit 12 to bit 23) of the data word - e.g. to
400 000 - instead of 800 000.
•
Read off the frequency-counter display again, e.g. 10.000001 MHz.
•
Change the left-hand segment of the data word, until the counter indicates precisely
10.000000 MHz.