TB 9-6625-1866-50
c. Turn VOLTS RANGE, switch to 500, NULL switch to VTVM, and all 5 attenuator
switches to zero.
d. Set UUT power switch to ON and allow approximately 15 minutes for equipment to
warm up and stabilize. If UUT is Model 801B 48 hours (in upright position) may be
required for stabilization of readings when UUT has been tilted more than 45.
e. Set meter needle on zero with upper ZERO control.
f. Turn NULL switch first to 10 V and then to 1 V and check that meter needle
remains on zero.
g. With NULL switch set to 0.1 V, adjust lower ZERO control to set meter needle on
zero.
h. Turn NULL switch to 0.01 V and check that meter needle remains on zero.
i. Turn NULL switch to VTVM and VOLTS RANGE switch to .5.
NOTE
When the UUT is not within tolerance, perform the specified
adjustment and continue the performance check. When the
UUT is not within tolerance and no adjustment is specified, the
deficiency must be corrected before continuing with the
procedure.
WARNING
HIGH VOLTAGE is used during the performance of this
procedure. DEATH ON CONTACT may result if personnel fail
to observe safety precautions.
8. Dc VTVM and Null Range
a. Performance Check
(2) Adjust dc voltage standard for full-scale indication (+500) on UUT meter. Dc
voltage standard will indicate between 0.480 and 0.520 volts. If not, perform b(1) and (2)
below.
(3) Reverse polarity of UUT input and adjust dc voltage standard for full-scale
(-500) indication on UUT. Dc voltage standard will indicate between 0.480 and 0.520 volt.
(4) Reverse polarity of UUT input.
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