Model 3 Radiation Survey Meter

Ludlum Measurements

Ludlum Model 3 survey meter

The Ludlum Model 3 Survey Meter is the industry work horse of radiation survey meters. The meter features a rugged design with  microprocessor electronics. With proper care, the Ludlum Model 3 will last decades. It operates on two D cells for approximately 2000 hours. The unit includes adjustable high voltage to 1500 volts and includes external calibration controls. The four counting ranges are x0.1, x1, x10, x100. (Dual scale, mR/hr & cpm available on special request.) Typical Counting Range is from 0 - 200 mR/hr, or 0 - 500,000 cpm. The Model 3 is supplied with built-in speaker, strain relief cable, probe clip-on handle, two D cell batteries and standard factory calibration. Model 44-3 or 44-2 gamma scintillator probes and many others can also be used with this meter.

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Used Model 3 Survey meter with 44-9 probe available - save money

Indicated Use: General purpose survey
Compatible Detectors: G-M, scintillation
Meter Dial: 0 - 2 mR/hr, or 0 - 5k cpm, BAT TEST (others available)
Multipliers: X0.1, X1, X10,X100
Linearity: Reading within ±10% of true value with detector connected
Connector: Series "C" (others available)
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 ± 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 Live: Typically greater than 2000 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: 6.5" (16.5 cm)H X 3.5" (8.9 cm)W X 8.5" (21.6 cm)L
Weight: 3.5 lbs. (1.6 kg) including batteries