Tektronix PSC1125, Instruction Manual

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Adjustment Procedures
PSC 1125 Digital Television Parallel-to-Serial Converter Instruction Manual
6-3
To avoid serious injury, do not touch exposed connections or
components when operating the instrument with the protective enclosure
removed. Dangerous potentials exist at several points within the converter.
1. Connect the power cord to turn on the power.
2. Locate the test points: TP010, TP012, TP014, TP018, TP030, TP040, and
TP050 located on the A10 board. See Figure 6–1.
3. Locate the variable resistor VR1 on the Power Supply board. See Figure 6–2.
4. Adjust the voltages:
a. Connect the DMM test leads to the TP018 and the chassis ground.
b. Turn the VR1 clockwise or counterclockwise so that the voltage at the
TP018 is in the range b4.9 V and +5.1 V.
c. Verify and adjust the VR1 so that the voltages at all the other test points
fall within the ranges between the lower and upper limits listed in
Table 6–2.
Table 6-2: Test points and voltage ranges
Test points Typical voltage Lower limit Upper limit
Adjustment