| Parameter | Specification |
|---|---|
| Measuring Range | 0.1 … 1000 µR/sec |
| Maximum Counting Rate | ≤ 650 pulses/sec |
| Gamma Sensitivity (Cs‑137) | 6.5 … 9.5 pulses/sec at 10 µR/sec |
| Working Voltage | 350 … 475 V |
| Start of Counting Voltage | 260 … 320 V |
| Plateau Length | ≥ 100 V |
| Pulse Amplitude | ≥ 50 V |
| Plateau Slope | ≤ 0.15 % / V |
| Dead Time (at 400 V) | 64 µsec |
| Background Noise | ≤ 0.2 pulses/sec |
| Tube Diameter | ~6 mm |
| Tube Length | ~21 mm |
| Weight | ~0.8 g |
These specifications are standard for this miniature GM tube and used for gamma/beta radiation detection. Soviet-Tubes+1
✔ Compact and lightweight for small portable devices
✔ Low background noise for accurate measurements
✔ Wide voltage operating range
✔ Compatible with many DIY and industrial Geiger counter projects
✔ Carefully tested and ready to use
1 × SBM‑21 Geiger Counter Tube
Protective packaging
Ships within 1–2 business days
Carefully packed to avoid damage
Worldwide shipping available
Returns accepted if the item is not as described.