Ludlum Model 3-98 Survey Meter

INDICATED USE: Alpha, beta, low energy gamma survey
DETECTORS: Controlled by selector switch
INTERNAL: Pancake style G-M detector with 1.7 plus or minus 0.3 mg/cm² window
AREA: Active - 15 cm²
Open - 12 cm²
EFFICIENCY(4pi geometry): 5% - C-14; 23% - Sr-90/Y-90; 19% - Tc-99; 33% - P-32; 15% - Pu-239
SENSITIVITY: Typically 3300 cpm/mR/hr (Cs-137 gamma )
ALPHA BETA SHIELD: Retractable 211 mg/cm² phenolic slide
EXTERNAL: Model 44-3 low energy gamma scintillator
EFFICIENCY(4pi geometry): Typically 19% or 675 cpm/microR/hr (I-125)
ENERGY RANGE: Recommended 5 keV - 60 keV
CONNECTOR: Series "C" (others available)
METER DIAL: 0 - 5k cpm, BAT TEST (others available )
MULTIPLIERS: X0.1, X1, X10, X100
LINEARITY: Reading within plus or minus 10% of true value with detector connected
AUDIO: Built in unimorph speaker with ON/OFF switch (greater than 60 dB at 2 feet )
CALIBRATION CONTROLS: Accessible from front of instrument (protective cover provided )
HIGH VOLTAGE: Adjustable from 200 - 1500 volts
THRESHOLD: 30 mV plus or minus 10 mV
RESPONSE: Toggle switch for FAST (4 seconds) or SLOW (22 seconds) from 10% to 90% of final reading
RESET: Push-button to zero meter
POWER: 2 each "D" cell batteries (housed in sealed compartment that is externally accessible )
BATTERY LIFE: Typically 600 hours with alkaline batteries (battery condition can be checked on meter )
METER: 2.5" (6.4 cm) arc, 1 mA analog type
CONSTRUCTION: Cast and drawn aluminum with beige polyurethane enamel paint
TEMPERATURE RANGE: -4° F(-20° C) to 122° F(50° C)
May be certified for operation from -40° F(-40° C) to 150° F(65° C)
SIZE: 9"(22.9cm)H X 3.5"(8.9cm)W X 8.5"(21.6cm)L
WEIGHT: 5.6 lbs (2.5 kg) including batteries and detector

Common Meter Dials


202-002 0 - 5k cpm For Any Detector	202-608 0-6.6k cpm; 0-2 mR/hr For Model 44-9; 44-9-18; 44-40; 44-88; 44-89; 44-94	202-664 0-6.6k cpm; 0-20 mSv/h For Model 44-9; 44-9-18; 44-40; 44-88; 44-89; 44-94