Model 194 Series
User’s Manual
Section 5
Ludlum Measurements, Inc.
Page 5-1
October 2020
Calibration
Calibration controls are under the CAL cover on the front panel. The
controls may be adjusted with an 1/8-inch blade screwdriver.
Non-Radiation Adjustment
AUDIO CALIBRATION:
Potentiometer marked AUD may be adjusted
as desired. Default setting is to adjust to 2-5 clicks per second with detector
at background levels of radiation. If audio potentiometer is set completely
counter-clockwise, audio is completely quiet until approximately 100 µrem/hr
(1.0 µSv/h).
Calibration Equipment Required
All instruments used in calibrating the Model 194 must be calibrated
by standards traceable to the National Institute of Standards and
Technology and must have a current calibration label attached.
A voltmeter or multimeter, capable of measuring DC voltage from
0.1 mV to 10 V
A
137
Cs gamma range with beta shield, capable of producing a
gamma field from 100 µrem/hr to 200 mrem/hr (2 µSv/h to 2
mSv/h). For the overload check, a source that is ten times bigger is
needed.
Section
5
