Ludlum Measurements 2200 - Calibrating Threshold to 100 keV;Turn

Model 2200 Scaler Ratemeter
Ludlum Measurements, Inc. Page 13 March 2016
 Switch the window ON-OFF to ON.
 Increase the HV until the source peaks on the ratemeter. Increase the
range switch as needed to prevent the meter from exceeding full scale.
 The THRESHOLD dial is now calibrated to 10 keV/turn. The
WINDOW control may be widened or narrowed without affecting the
THRESHOLD setting. (As now calibrated, the instrument will respond
only to radiation energies between 55 keV and 65 keV. Adjust the
THRESHOLD dial for other energies of interest.
Procedures to Calibrate
Threshold to 100 keV/Turn
Initial Model 2200 control settings:
 Switch the window ON-OFF to OFF.
 Ratemeter RANGE selector switch at X10.
 THRESHOLD dial is at 6.42.
 WINDOW dial is at 0.40.
 HV dial is at 0.00.
 Connect the Model 44-2 detector to the instrument.
 Turn the power switch to the appropriate power supply.
Operation and Calibration
 Expose
137
Cs to detector.
 Increase HV setting until count from source just starts to count.
 Switch window ON-OFF to ON.
 Increase HV until source peaks on ratemeter. Increase RANGE switch
as needed to prevent meter from exceeding full scale.
 THRESHOLD dial is now calibrated to 100 keV/Turn. The WINDOW
control may be widened or narrowed without affecting the threshold
setting. (As now calibrated, the instrument will respond only to radiation
energies between 642 keV and 682 keV. Adjust THRESHOLD dial for
other energies of interest.)