Teledyne 2010A Operating Instructions Manual page 64

4 Operation
6. Press and hold the RIGHT key for approximate 5 to 7
seconds.
7. Select AUTO and set the reading to span gas level. Press
ENTER key.
Repeat steps 1 to 7 if more than two ranges need to be setup.
4-30 Part I Teledyne Analytical Instruments
Model 2010A