TB 9-4931-290-50
Figure 2. Model 421A (below S/N 901) adjustments.
a. Performance Check
(1) Adjust decade resistor to 1 megohm (999.999 ohms on model 336) and connect
across TI output. This connection remains throughout the dc voltage check except where
instructed specifically to change.
(2) Connect multimeter to TI output.
(4) Position controls as listed in (a) through (c) below:
(a) MODE switch to DC POS.
(b) RANGE switch to 100 V.
(c) OUTPUT VOLTAGE controls to TEN0.00.
(5) Measure and record TI output for each RANGE listed in table 4.
OUTPUT
RANGE switch
Adjustments
VOLTAGE control
setting
Min
Max
setting
100 v
TEN0.00
99.7929
100.2070
b(10) through (15)
10 v
TEN.000
9.97928
10.02073
b(16) and (17)
1v
.TEN000
.997905
1.00210
b(18) and (19)
100 mV
TEN0.00
.099768
.100232
b(20) and (21)
10 mV
TEN.000
.009954
.010046
b(22) and (23)
1 mV
.TEN000
.000973
.001027
b(24) and (25)