Rohde & Schwarz 1138.4000, Руководство по обслуживанию

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Radio Unit R&S CRTU-RU Manual Test Procedure
1140.0050.82 1.13 E-4
REF OUT 1
The level and frequency are checked.
Int. 10 MHz:
¾
Set CRTU Radio Unit to internal reference.
¾
Measure at REF OUT 1: 10 MHz, level > 1.4 V(pp).
REF IN
signal:
¾
Set CRTU Radio Unit to external reference.
¾
Feed in at REF IN: 52 MHz TTL, (as an alter16 dBm from signal)
¾
Measure at REF OUT 1: 52 MHz, level > 1.4 V(pp).
¾
Measure at REF OUT 1: frequency 52 MHz
±
1 Hz
¾
Feed in at REF IN: 1 MHz TTL, (as an alter16 dBm from signal
generator).
¾
Measure at REF OUT 1: 1 MHz, level > 0.5 V(rms) (1.4 V(pp)).
¾
Measure at REF OUT 1: frequency 1 MHz
±
1 Hz.
REF OUT 2
The level and frequency are checked. The CRTU Radio Unit and the frequency counter must be
synchronized (test setup REF2).
REF OUT 2
signal 13 MHz or
10 MHz:
¾
Set CRTU Radio Unit to external reference.
¾
Feed in at REF IN: 10 MHz sinewave, 0.5 V(rms).
¾
Set CRTU Radio Unit to REF OUT 2 13 MHz or 10 MHz (depending on SW;
menu Connection Control/Sync.) .
¾
Measure at REF OUT 2: 13 MHz or 10 MHz, level > 1.0 V(pp).
¾
Measure at REF OUT 2: frequency 13 MHz or 10 MHz
±
1 Hz.
TX Frequency Accuracy
Preparation: Test setup TX5, but CRTU Radio Unit not synchronized with frequency
counter/analyzer and no external trigger.
CRTU Radio Unit connector RF3 OUT.
Control:
¾
Set CRTU Radio Unit to desired frequency, level 0 dBm.
Test:
¾
Determine frequency deviation from nominal frequency.
TX Frequency Settling Time
Preparation: Test setup TX5.
CRTU Radio Unit connector RF3 OUT.
CRTU Radio Unit: Ramping off, hopping on, F1 = start freq., F2 = stop freq.
Analyzer: Sweep time 1 ms, Center = stop frequency, FM demodulation,
real time off, BW 50 kHz, 1 kHz/Div, external trigger, Slope
negative