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Ludlum 2241-2RK w/44-9 Probe Ludlum Get Quote



The Ludlum Model 2241-2RK is a portable general-purpose survey meter equipped with a Geiger-Mueller detector for measurement of alpha, beta and gamma radiation. The Model 2241 operated in either Ratemeter Mode with a moving decimal point and six-digit in Scaler Mode. The unit has both visual and audible alarms.

Key Features

  • Alpha, Beta, Gamma radiation surveys
  • NIST-Traceable certificate of calibration

Technical Specifications

Ratemeter Displays in R/hr, Sv/hr, cpm or cps
Display Auto-ranging from 0.0 micro R/hr to 9999 R/hr; 0.000 micro Sv/hr to 9999 Sv/hr; 0 cpm to 999k cpm; or 0 to 100k cps
Audiio Alarm Built-in unimorph speaker with ON/OFF switch > 60 dB at 2ft.
Alert/Alarm Indicated by enunciator on display and audible tone
Power Two \"D\" cell batteries, about 200 hours operation.
Detector Pancake type halogen quenched Geiger-Mueller
Sensitivity Typically 3300 cpm, mR/hr (137Cs gamma)
Operating Voltage 900 volts
Dimensions 1.8\" x 2.7\" x 10.7\"
Weight 1 lb


  US Metric
H x W x L 6.5 x 3.5\" x 8.5\"\" 165 x 89 x 216 mm


  US Metric
H x W x L 3.5 lbs including batteries 1.6kg including batteries