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Model 133 Series

Gamma Detector

The Model 133 Series of Geiger-Mueller (GM) gamma survey detectors can be used with any portable ratemeter, scaler instrument, or area monitor that provides the appropriate amount of voltage (see specifications) with an input sensitivity of 30 ± 10 mV.

Waterproof versions of these detectors (all 133-x-1 versions) have the same characteristics as non-waterproof models, other than they are waterproof, contain an O-ring, and do not have a “C” connector on the probe end (base). A 30-meter (100 foot) cable is hard-wired into the detector. They weigh slightly more and have a slightly larger diameter than the non-waterproof versions. They are submersible up to 30 m (100 ft).

Model 133-2

Models 133-2 and 133-2-1

Part Number	133-2: 47-1717 133-2-1: 47-2450^†
Indicated Use	Gamma area monitoring
Detector Type	Energy compensated, halogen quenched GM, 30 mg/cm² stainless steel
Linear Range	*Without DTC: 1 µSv/h to 2 mSv/h (0.1 to 200 mR/hr) With DTC:* 1 µSv/h to 10 mSv/h (0.1 mR/hr to 1 R/hr) With SCC or DTC2:** 1 µSv/h to 50 mSv/h (0.1 mR/hr to 5 R/hr)
Typical Sensitivity (¹³⁷Cs gamma)	100 cpm per µSv/h (1000 cpm per mR/hr)
Energy Response (60 keV - 3 MeV)	Within 25% of true value
Typical Background (10 µR/hr field)	12 cpm
Typical Dead Time	50 µs
Operating Voltage	550 Vdc
Connector	133-2: Series "C". Other connectors are available upon request. 133-2-1: 30 m (100 ft) hard-wired cable
Size (Dia x L)	2.5 x 10.2 cm (1 x 4 in.)
Weight	0.090 kg (0.20 lb)

*DTC: Dead Time Correction, available on some instruments
**SCC or DTC2: Series Correction Constant or 2nd order Dead Time Correction, available on some instruments
†: Waterproof

Model 133-3

Models 133-3 and 133-3-1

Part Number	133-3: 47-1314 133-3-1: 47-4387^†
Indicated Use	Gamma area monitoring
Detector Type	Energy compensated, halogen quenched GM, 30 mg/cm² stainless steel
Linear Range	*Without DTC: 1 µSv/h to 10 mSv/h (0.1 mR/hr to 1 R/hr) With DTC:* 1 µSv/h to 50 mSv/h (0.1 mR/hr to 5 R/hr) With SCC or DTC2:** 1 µSv/h to 250 mSv/h (0.1 mR/hr to 25 R/hr)
Typical Sensitivity (¹³⁷Cs gamma)	45 cpm per µSv/h (450 cpm per mR/hr)
Energy Response (60 keV - 3 MeV)	Within 25% of true value
Typical Background (10 µR/hr field)	6 cpm
Typical Dead Time	50 µs
Operating Voltage	550 Vdc
Connector	133-3: Series "C". Other connectors are available upon request. 133-3-1: 30 m (100 ft) hard-wired cable
Size (Dia x L)	133-3: 2.2 x 10.2 cm (0.88 x 4 in.) 133-3-1: 2.5 x 10.2 cm (1 x 4 in.)
Weight	0.090 kg (0.20 lb)

*DTC: Dead Time Correction, available on some instruments
**SCC or DTC2: Series Correction Constant or 2nd order Dead Time Correction, available on some instruments
†: Waterproof

Model 133-4

Models 133-4 and 133-4-1

Part Number	133-4: 47-1674 133-4-1: 47-2451^†
Indicated Use	Gamma area monitoring
Detector Type	Energy compensated, halogen quenched GM, 30 mg/cm² stainless steel
Linear Range	*Without DTC: 10 µSv/h to 20 mSv/h (1 mR/hr to 2 R/hr) With DTC:* 10 µSv/h to 100 mSv/h (1 mR/hr to 10 R/hr) With SCC or DTC2:** 10 µSv/h to 500 mSv/h (1 mR/hr to 50 R/hr)
Typical Sensitivity (¹³⁷Cs gamma)	10 cpm per µSv/h (100 cpm per mR/hr)
Energy Response (60 keV - 3 MeV)	Within 25% of true value
Typical Background (10 µR/hr field)	≤ 1 cpm
Typical Dead Time	50 µs
Operating Voltage	550 Vdc
Connector	133-4: Series "C". Other connectors are available upon request. 133-4-1: 30 m (100 ft) hard-wired cable
Size (Dia x L)	133-4: 2.2 x 10.2 cm (0.88 x 4 in.) 133-4-1: 2.5 x 10.2 cm (1 x 4 in.)
Weight	0.090 kg (0.20 lb)

*DTC: Dead Time Correction, available on some instruments
**SCC or DTC2: Series Correction Constant or 2nd order Dead Time Correction, available on some instruments
†: Waterproof

Model 133-6

Models 133-6 and 133-6-1

Part Number	133-6: 47-1718 133-6-1: 47-2452^†
Indicated Use	Gamma area monitoring
Detector Type	Energy compensated, halogen quenched GM, 30 mg/cm² stainless steel
Linear Range	*Without DTC: 40 μSv/h to 60 mSv/h (4 mR/hr to 6 R/hr) With DTC:* 40 μSv/h to 400 mSv/h (4 mR/hr to 40 R/hr) With SCC or DTC2:** 40 μSv/h to 1 Sv/h (4 mR/hr to 100 R/hr)
Typical Sensitivity (¹³⁷Cs gamma)	1.8 cpm per μSv/h (18 cpm per mR/hr)
Energy Response (60 keV - 3 MeV)	Within 25% of true value
Typical Background (10 µR/hr field)	≤ 1 cpm
Typical Dead Time	50 µs
Operating Voltage	550 Vdc
Connector	133-6: Series "C". Other connectors are available upon request. 133-6-1: 30 m (100 ft) hard-wired cable
Size (D x L)	133-6: 2.2 x 10.2 cm (0.88 x 4 in.) 133-6-1: 2.5 x 10.2 cm (1 x 4 in.)
Weight	0.090 kg (0.20 lb)

*DTC: Dead Time Correction, available on some instruments
**SCC or DTC2: Series Correction Constant or 2nd order Dead Time Correction, available on some instruments
†: Waterproof

Model 133-7

Models 133-7 and 133-7-1

Part Number	133-7: 47-1216 133-7-1: 47-2453
Indicated Use	Gamma area monitoring
Detector Type	Energy compensated, halogen quenched GM, 30 mg/cm² stainless steel
Linear Range	*Without DTC: 250 μSv/h to 300 mSv/h (25 mR/hr to 30 R/hr) With DTC:* 250 μSv/h to 1 Sv/h (25 mR/hr to 100 R/hr) With SCC or DTC2:** 250 μSv/h to 10 Sv/h (25 mR/hr to 1000 R/hr)
Typical Sensitivity (¹³⁷Cs gamma)	0.42 cpm per μSv/h (4.2 cpm per mR/hr)
Energy Response (60 keV - 3 MeV)	Within 25% of true value
Typical Background (10 µR/hr field)	≤ 1 cpm
Typical Dead Time	50 µs
Operating Voltage	460 Vdc
Connector	133-7: Series "C". Other connectors are available upon request. 133-7-1: 30 m (100 ft) hard-wired cable
Size (D x L)	133-7: 2.2 x 10.2 cm (0.88 x 4 in.) 133-7-1: 2.5 x 10.2 cm (1 x 4 in.)
Weight	0.090 kg (0.20 lb)

*DTC: Dead Time Correction, available on some instruments
**SCC or DTC2: Series Correction Constant or 2nd order Dead Time Correction, available on some instruments
†: Waterproof

Model	Description	Part Number
133-2 Series	GM Tube	01-5295
133-4 Series	GM Tube	01-5306
133-7 Series	GM Tube, with 01-5055 Shield	01-5045