Racal Instruments 3152, User Manual

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Maintenance and Performance Checks 5-12
8. Change the Model 3152 PHAS2:ADJ setting to 0
E
and
PHAS2:FINE setting to 36
E
. Verify counter phase
readings as shown below. Note the exact phase reading.
3152 FREQ. PULSE GENERATOR
SETTING FREQ. SETTING COUNTER READING
10.00 KHz 10.00 KHz Recorded result from
step 7 +36
E
±0.36
E
Adjustments
Environmental
Conditions
Adjustments should be performed under laboratory conditions
having an ambient temperature of 24
o
C ±2
o
C and relative humidity
of less than 70%. If the instrument has been outside this range,
allow at least one additional hour for the instrument to stabilize
before beginning the adjustment procedure. Between adjustments,
always leave the top cover on the unit to keep the internal
temperature as stable as possible.
Warm-Up Period
Most equipment is subject to a small amount of drift when first
turned on. To ensure long term calibration accuracy, turn on the
power to the Model 3152 and allow it to warm-up for at least 30
minutes before beginning the adjustment procedure.
Recommended Test
Equipment
Recommended test equipment for calibration is listed at the
beginning of this chapter in the section entitled Recommended
Test Equipment. Test instruments other than those listed may be
used only if their specifications equal or exceed the required
characteristics.
Adjustment
Procedures
All adjustments are performed with the POWER ON. The side
covers should be removed to allow access to test points and
adjustments.
WARNING
Special care should be taken to prevent contact with live
circuits or the power line area. This could cause an electrical
shock resulting in serious injury or death. Use an isolated tool
when making adjustments.
When necessary, refer to the component layouts for
determining adjustment points. Follow the procedure in the
sequence indicated as some adjustments are interrelated and
dependent on the proceeding steps.
Verify that the waveform generator is functioning according to
the performance checks. Ensure that all results are within or
close to the range of the required specifications; otherwise,
refer to the troubleshooting procedures given later in this
section.
Perform the following adjustment procedure. If an adjustment
cannot be made to obtain a specific result, refer to the
troubleshooting procedures.