Racal Instruments 3152A, Руководство пользователя

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3152A User Manual
Racal Instruments
©
2001 Maintenance and Performance Checks 5-27
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 μ s
period, repeated every 1 ms
2 U56 through U60 pin 9 Positive going pulses; 200 μ s width, 1 ms period
3 U49 pin 2 Positive going pulses; 400 μ s width, 1 ms period
4 U49 pin 5 Positive going pulses; 300 μ s width, 1 ms period
PLL Checkout
Problems with the phase lock loop circuits can be detected if
the Model 3152A 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 3152A
to the factory default using the *RST command. Configure the
Model 3152A 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 0 KHz square waveform, ECL logic level
2 U513 pin 11 20 μ s width positive going pulses; 100 μ s period,
ECL
3 Q502, Q503 collectors 3 Vp-p narrow pulses on 5 V offset