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Miniray Dosimeter – Technical Data

Detector type: VA-Z-115.1 Geiger-Mueller tube

Dose limit: 0.5 R/h (beta and gamma radiation)
Proposed anode voltage: 450 V
Zero effect: approx. 35 imp/min
Life span: approx. 1010 imp
Operation temperature range: -50 to +70°C
Wall material surface mass: 35 to 55 mg/cm2
Active length: 27 mm
Gas filling: neon-halogene

Measuring unit: µSv/h (pronunciation: micro Sievert per hour)

This measuring unit relates to the dose equivalent.

Measuring ranges: three automatically adjusted measuring ranges

range I 0,00 to 15,00 µSv/h
range II 13,0 to 150,0µSv/h
range III 130 to 2000 µSv/h

Display: 3 and 1/2 digits LCD display with low battery voltage indication

A single figure 1 appearing at the highest decimal value indicates a bad function.

Time constant: approx. 5 seconds

Measuring accuracy: within 20% in all measuring ranges (for 137Cs)

Energy dependence: within 20% between 80 keV and 3 MeV

Direction dependence: within 20% for a space angle of 120 degree

Temperature range: 0°C to +50°C

Temperature change effect: below 10%

Humidity: 0 to 85 % relative

Pressure: 600 to 1300 mbar

Operating position: Neutral

Warm up time: None

Sound signal: Ceramic buzzer

In measuring range I (0.00 to 14.00 µSv/h) each detected particle causes a sound signal. In the two higher measuring ranges the sound signal is continuous and serves for indicating the operation of the instrument. Stopping the sound signal indicates incapability of the instrument for measuring (for instance if too high level unprocessable for the detector should be measured).

Power supply: One piece of 9V radio battery (6LR61, 6AM6, 6LF22 type)

Operating time:

approx. 40 hours for standard battery
approx. 100 hours for alkali-manganese battery

Size: 150 * 80 * 30 mm

Weight: approx. 300 g (without battery)

Miniray Dosimeter – Operation Manual

Principal Concepts of Radioactivity

Back to Miniray Dosimeter Main Page

Technical Data and Operation Manual (downloadable pdf-file)

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