Monitor 4

Monitor 4 Radiation DetectorThe Monitor 4 is compact, analog radiation detector. A general purpose survey meter capable of detecting alpha, beta, gamma, and x-rays over 3 selectable ranges. Proven and reliable over decades of use in the industry, the Monitor 4 has evolved into one of the best analog radiation detectors of today. Simple and ergonomic , a red count light flashes and a beep sounds with each count detected. Battery check and silent operation with the flick of your thumb.

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Detector

Halogen-quenched uncompensated GM tube with thin mica window 1.5-2.0 mg/cm2 thick.
Effective diameter of window is 9.1 mm (.36 in.).

Operating Range

0-.5, 0-5, 0-50 mR/hr 0-500, 0-5,000, 0-50,000 CPM or 0-5, 0-50, 0-500 μSv/hr (SI Scale Meter Option)

Energy Sensitivity

1000 CPM/mR/hr (Cs137).
Detects alpha down to 2.5 MeV; typical detection efficiency at 3.6 MeV is greater than 80%. Detects beta at 50 keV with typical 35% detection efficiency and beta at 150 keV with typical 75% detection efficiency.  Detects gamma and x-rays down to 10 keV typical through the window, 40 keV minimum through the case.

Accuracy

Typically ±15% of reading (Cs137)

Monitor 4 Energy Response

Range Switch

X1, X10, X100, Battery Check.

Audio Indicator

Internally mounted beeper (can be turned off for silent operation).

Display

Analog Meter holds full scale in fields as high as 100X maximum reading. CPM & mR/hr scale. Optional SI Scale Meter Available


Outputs

Headphone, 3.5 mm jack with pulse out.

Includes

Carrying Case w/ Belt Clip

Options

SI Meter Option, Observer Software

Limited Warranty

1 year limited warranty

Monitor 4 Kits

Build your own Monitor 4! Learn about how a Geiger counter works!

Power Requirements

9-volt alkaline battery (included). Approx. 2,000 hrs. at normal background

Temperature Range

-20° to 55°C (-4° to 131°F)

Weight

M4: 200 g (7.1 oz) M4EC: 224 g (7.9 oz)

Outputs

3.5 mm jack with pulse out.

Size

209 x 71 x 50 mm (8.2 x 2.8 x 1.9 in.)