Rohde & Schwarz 1138.4000, Руководство по обслуживанию

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Manual Test Procedure Radio Unit R&S CRTU-RU
1140.0050.82 1.12 E-4
Control and Sync Bus Test 10 – Special Path Test
Purpose: Test remaining connections.
Test Setup: Connect one CTRL-Cable from CONTROL A of the RU to CONTROL A of the Test
Box and one cable from CONTROL B of the CRTU-RU to CONTROL B of the Test
Box.
Error case: Check the cable carefully, replace the motherboard if this does not help.
Reference Frequencies
For different range of adjustment of the internal reference oscillator, the synchronization with an external
reference frequency is checked.
Note: The resolution of the frequency counter/analyzer should be max. 1/10 of the maximum
permissible deviation.
REF IN
The frequency and level ranges and the pull-in range are checked. The signal generator and the
frequency counter must be synchronized (test setup REF1).
Preparation:
¾
Feed in at REF IN: 52 MHz sinewave, 0.5 V(rms)
¾
Connect frequency counter to RF3 OUT.
Control:
Set CRTU Radio Unit to external reference 52 MHz, RF 1 GHz (menu RF
ANALYZER/ GENERATOR .)
Test:
Use frequency counter to measure frequency deviation from 1 GHz.
Preparation:
¾
Feed in at REF IN: 1 MHz sinewave, 0.5 V(rms).
¾
Connect frequency counter to RF3 OUT.
Control:
¾
Set CRTU Radio Unit to external reference 1 MHz, RF 1 GHz.
Test:
¾
Use frequency counter to measure frequency deviation from 1 GHz.
Preparation:
¾
Feed in at REF IN: 10.000 050 MHz sinewave, 1.4 V(rms).
¾
Connect frequency counter to RF3 OUT.
Control:
¾
Set CRTU Radio Unit to external reference 10 MHz, RF 1 GHz.
Test:
¾
Use frequency counter to measure frequency deviation from 1.000 005 000 GHz.
Preparation:
¾
Feed in at REF IN: 9.999 950 MHz sinewave, 1.4 V(rms).
¾
Connect frequency counter to RF3 OUT.
Control:
¾
Set CRTU Radio Unit to external reference 10 MHz, RF 1 GHz.
Test:
¾
Use frequency counter to measure frequency deviation from 0.999 995 GHz.