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Geiger-Muller tube
SBM-19, SBM-19M – seven sectional Geiger-Muller tubes, used to measure the exposure dose and evaluation of the energy spectrum of gamma radiation energy based on the relative number of coincident pulses at the output of the counter.

Notes on sensitivity:

This is a highly sensitive, robust tube. The excellent response to even small doses of radiation comes thanks to its cathode material and relatively large size. The big size doesn’t increase risks of damage or mechanical failure, due to the tube being enforced with parallel rings. It is perfect for monitoring equipment and DIY dosimeters, superior to the SBM-20 in this sense. The following chart shows the average of the background readings over a period of 24 hours and each point in the chart was computed using another average of 60 independent, consecutive measurements. The dosimeter used to take the measurements has 1 minute resolution.

Background readings: 80CPM for a background radiation level of 0.12uSv/h

Datasheet:

Operating Voltage Range (volts): 350 – 475V
Initial voltage (volts): 260 – 320V
Recommended Operating Voltage (volts) : 400V
Minimum Dead Time (at U=400V, micro sec): 250us
Plateau Inclination: 0.1%/V
Working temperature: -60 to + 70 C
Counting speed: max. 2000 imp/s
Inherent counter background (cps) 1.83 Pulses/s
Interelectrode Capacitance 10pF
Load Resistance 5 – 10 MOhms
Sensitivity to gamma radiation:
MED – 3.0 mR ∙ s -1;
247.5 mR -1 ± 26mkR -1
Length: 195mm
Diameter: 18mm

Links:

http://www.gstube.com/data/2397/

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