Racal Instruments 3152, User Manual

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Maintenance and Performance Checks 5-22
The next checkout is done on the Model 3152 configured to
operate in burst mode with 5 bursts. Use the following command
to configure the Model 3152:
Remote Commands: :FUNC:MODE USER
:TRAC:SEL 1
:INIT:CONT OFF
:TRIG:BURS: ON
:TRIG:COUN 5
:OUTP ON
Connect an external trigger source to the front panel TRIG IN
connector. Set external trigger frequency to 1 KHz. Proceed with
the checkout procedure given in Table 5-5.
Table 5-5 Burst Generator Checks
Step Test Point Expected Result
1 U56 through U60 pin 2 Five negative going pulses; 2 ns width, 100 µs period,
repeated every 1 ms
2 U56 through U60 pin 9 Positive going pulses; 200 µs width, 1 ms period
3 U49 pin 2 Positive going pulses; 400 µs width, 1 ms period
4 U49 pin 5 Positive going pulses; 300 µs width, 1 ms period
PLL Checkout
Problems with the phase lock loop circuits can be detected if the
Model 3152 accepts word serial commands and responds correctly
to word serial queries, but fails to lock to a valid external signal. If
there is a problem with the PLL circuits, proceed with the checkout
procedure given in Table 5-6.
Before starting the following procedure, reset the Model 3152 to the
factory default using the *RST command. Configure the Model
3152 to PLL mode, 10 MHz frequency and square waveform. Use
the following commands after loading the waveforms.
Remote Commands:
:RES
:OUTP ON
:FREQ 10E6
:PHAS2:LOCK ON
:TRIG:LEV 0
Connect an external 10 KHz, 2 Vp-p square waveform to the TRIG
IN BNC. Proceed with the checkout procedure given in Table 5-6.
Table 5-6 PLL Checkout Procedure
Step Test Point Expected Result
1 U513 pin 6 10 KHz square waveform, ECL logic level
2 U513 pin 11 20 µs width positive going pulses; 100 µs period, ECL
3 Q502, Q503 collectors 3 Vp-p narrow pulses on 5 V offset