Ludlum Model 44-3 Low E gamma NaI Survey Probe. Can be paired with Ludlum 3-98 meter or any other meter with HV adjustment.
Most have a C connection, we do have a couple BNC connection.
Specifications
INDICATED USE: 125I and low energy gamma survey
SUGGESTED INSTRUMENTS: general purpose survey meters, ratemeters, and scalers
DETECTOR TYPE: scintillator, 2.5 cm (1 in.) diameter x 1 mm thick Nal(TI) crystal
ENTRY WINDOW: 18.4 mg/cm²
WINDOW AREA: 5 cm² (0.8 in²) active and open
SENSITIVITY: 675 cpm/µR/hr (125I)
BACKGROUND (10 µR/hr):
EFFICIENCY (4π): 33.5%–125I (based on 129I efficiency of 18%)
RECOMMENDED ENERGY RANGE: 10–60 keV
RECOMMENDED ENERGY RANGE: 10–60 keV
ENERGY RESPONSE: energy dependent
PHOTOMULTIPLIER TUBE: 3.8 cm (1.5 in.) diameter
OPERATING VOLTAGE: typically 500–1200 volts
CONNECTOR: series “C”
SIZE: 5.1 X 17.8 cm (2 x 7 in.) (Dia x L)
WEIGHT: 0.5 kg (1 lb)