Thermo Fisher Ion Chamber RO-20

Did you observe the polarity indicators when installing the AA batteries?

Replace 12V alkaline batteries if necessary

Did you observe the polarity indicators when installing the 12V batteries?

Is the air pressure suitable for calibration?

Select the Zero position on the Function Switch and zero the meter

Remove the plastic cover on the side of the can

Position the RO-20 so that the ion chamber is in a gamma field of known intensity

Adjust the calibration control for the proper meter indication

Record the meter reading near the '4' mark for best accuracy

Check the color of the desiccant crystals

Slip the hose from the fitting on the old desiccant pack and onto the new one

Select drying method for silica gel crystals

Store dried crystals in tightly sealed containers

Ensure the snap-on cap hole is not covered or clogged

Flip the light switch in both directions and confirm lamps are functional

Measure the voltage of the AA cells with Function Switch set to Battery 1

Is the measured voltage within the expected range?

Measure the voltage of the 3 ea 12V alkaline batteries with Function Switch set to Battery 2

Is the measured voltage within the expected range?