I’ve bought this cute mini Geiger tube from eBay. It’s cheap… in the order of 10-15€. The interesting thing about this tube is it’s size: 20mm lenght per 9mm diameter that makes it a good choice to make a portable dosimeter.
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It’s sensibility is not hight but is better than SI-3BG. Another cool thing is it’s glass window. People around internet say that is a mica window for alpha particles but, I’ve testd it in contact with a piece of pechblende that, is a strong alpha+beta emitter sample and I’ve seen that it’s count rate is so small… like it ounts just beta+gamma.
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Tech info:
- Sensitivity: 1000-1500 Pulses/s/R/h
- Plateau inclination: 0.25%/V
- Working voltage: 360-440V
- Maximum registering range: 900 Roentgen/hour
- Lenght: 20mm
- Diameter: 9.3mm
- Weight: 4 grams
I’ve found on eBay a photo from a seller that sold it with it’s original connector… looks more an enclosure/socket than a connector.
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