Tektronix TLA715 Series, Руководство по обслуживанию

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Performance Verification Procedures
4- 6
TLA715 Dual Monitor Portable Mainframe Service Manual
Do the following to verify power supply performance:
Equipment
required DMM with test leads (item 5)
Two miniature probe-to-square pin adapters (item 3)
0.025-inch square pin (item 4)
Frequency counter (item 2)
Precision BNC cable (item 6)
Prerequisites Warm-up time: 30 minutes for the portable mainframe and test
equipment
Power-on, mainframe, and QA+WIN32 diagnostics pass
1.
Power off the portable mainframe and remove any modules installed in it.
2.
Power on the portable mainframe and connect the reference lead of a digital
voltmeter to chassis ground, such as the top of the power supply.
3.
Attach a 0.025-inch square pin to the probe tip of the other lead and insert it
into one of the pins on the backplane connectors listed in Table 4--4.
CAUTION.
Use of a square pin of other dimensions will damage the backplane
connectors.
The pins that should be carrying voltages are listed in Table 4--4. The arrange-
ment of J1 and J2 connectors on the backplane is shown in Figure 4--2. Measure
the power supply voltages with the voltmeter and compare each reading to the
values listed in the tables. If the voltages are within the ranges listed in the table,
the power supply is operating properly.
Table 4- 4: Power supply voltages and backplane connector pins
J1 pin Voltage (range) J2 pin Voltage (range)
Row A Row A
31 --12 V (--12.60 V to --11.64 V) 2 --2 V (--2.10 V to --1.90 V)
25 +5 V (4.875 V to 5.250 V)
Row C Row C
31 +12 V (11.64 V to 12.60 V) 4 --5.2 V (--5.460 V to --5.044 V)
31 +24 V (23.28 V to 25.20 V)
32 --24 V (--25.20 V to --23.28 V)
Checking Power
Supply Voltages