Introduction - LUDLUM MODEL 19 Manual

Model 19 MICRO R METER
1
Section
Ludlum Measurements, Inc.
Technical Manual

Introduction

T
he Ludlum Model 19 Micro R Meter utilizes an internally-mounted
2.5 x 2.5 cm (1 × 1 in.) NaI(T1) scintillator for optimum
performance in locating and measuring low-level (near background)
gamma radiation.
The unit features a push-button, lighted meter and was designed to be
moisture and dust resistant. The meter is housed in a rugged aluminum bezel
with waterproof seals. All controls, including a calibration potentiometer for
each range, are located on the front panel. Front-panel switches are rubber-
booted to seal out moisture and dust. A high-voltage (
provided to allow rapid plateau testing of the detector.
Five range divisions are provided in the 0-5000 micro R/hr spectrum. The
meter face is made up of two scales, 0-50 and 0-25, plus battery test. The 0-
50 scale corresponds to the 50, 500 and 5000 positions on the range selector
switch. The 0-25 scale corresponds to the 25 and 250 positions on the range
selector switch.
The instrument is capable of using either standard "
batteries or nickel-cadmium rechargeable batteries. However, the Model 19
does not include circuitry for recharging the batteries. The two "
batteries are located in an isolated compartment, easily accessible from the
front panel.
The Model 19 NaI scintillator is energy sensitive. An energy response curve
is included in section 10 of this manual for further reference.
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Section 1
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February 2012