TB 9-6625-1866-50
MC 6625-1866-50-3
Figure 3. Differential voltmeter (AN/USM-98B).
21. 0.5-Volt Range
a. Performance Check
(1) Turn NULL switch to VTVM and polarity switch to + (positive).
(2) Turn UUT A, B, C, D, and E dials to 4, 9, 9, 9, and 10.
(3) Connect dc voltage standard (A2, table 6) output to UUT input terminals, using
(4) Turn VOLTS RANGE switch to .5.
(5) Adjust dc voltage standard for full-scale indication on UUT meter.
(6) Turn NULL switch to 10, 1, .1, and .01 while adjusting dc voltage standard for
0 (zero) indication on UUT meter. Dc voltage standard will indicate between 0.49975 and
0.50025 volt. If not, perform b below.
(7) Turn NULL switch to VTVM.
(8) Adjust dc voltage standard for 0 (zero) indication on UUT meter.
b. Adjustments
(1) Turn NULL switch to VTVM.
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