SRS Labs SR850 - Manual (Page 251)

8-5
SR850 Service
[GAIN/TC]
<Sensitivity>
Rotate the knob to select 100 mV full scale
If the R reading (top display) is less than 1 mV, then proceed to the next step. If the reading is
greater than 1 mV, adjust the Voltage Input Offset pot until R is less than 1 mV.
11. Press
<Sensitivity>
Rotate the knob to select 1 mV full scale
If the R reading is less than 0.02 mV then proceed to the next step. If the reading is greater than
0.02 mV, adjust the Voltage Input Offset pot until R is less than 0.02 mV.
12. Remove the terminator from the A input. Leave the inputs open to adjust the current input offset.
Press
[INPUT]
<Input Source> Twice to select I
<Grounding> select Ground
<Coupling> select DC
[GAIN/TC]
<Sensitivity>
Rotate the knob to select 100 nA full scale
If the R reading (top display) is less than 1 nA, then proceed to the next step. If the reading is
greater than 1 nA, adjust the Current Input Offset pot until R is less than 1 nA.
13. Press
<Sensitivity>
Rotate the knob to select 1 nA full scale
If the R reading is less than 0.02 nA then proceed to the next step. If the reading is greater than
0.02 nA, adjust the Current Input Offset pot until R is less than 0.02 nA.
14. This completes the offset and common mode adjustment procedure.
15. Turn the unit OFF. Replace the magnetic shield at the front of the Analog board and replace the
card cage cover. Tighten the two cover screws. Replace the top lid. The lid slides forward and
down to engage the clip at the center front. Replace the four black screws to secure the lid.