All tubes are tested and fully functional.
These tubes are new, removed from unused Geiger counters. They have never been operated in service, but do not include the original box, manual, or metal protective cover.
Parcel will be well packed and shipped by air mail with a tracking number. Shipping usually takes 12–21 days, depending on your location.
If you need more tubes than listed or are looking for other Geiger tubes, photomultiplier tubes, vacuum tubes, or scientific equipment, please send me a message.
| Parameter | Specification |
|---|---|
| Tube Model | SI8B (СИ8Б) |
| Type | Geiger–Müller Counter Tube |
| Radiation Detected | Beta (β) & Gamma (γ) |
| Quenching Gas | Halogen |
| Condition | New, removed from unused Geiger counter (tested) |
| Operating Voltage Range | 400–475 V |
| Recommended Operating Voltage | 425 V |
| Starting Voltage | ≤340 V |
| Plateau Length | ≥75 V |
| Plateau Slope | ≤0.15 %/V |
| Maximum Dose Rate | Up to 1000 R/h |
| Dead Time | ≤190 µs |
| Background Count Rate | ≤0.5 pulses/s |
| Tube Capacitance | Approx. 4 pF |
| Operating Temperature | −60 °C to +85 °C |
✔ Genuine Soviet SI8B Geiger–Müller tube
✔ Detects beta and gamma radiation
✔ New tube removed from an unused Geiger counter
✔ Each tube is individually tested before shipping
✔ Stable operation and long service life
✔ Excellent for restoration, laboratory equipment, and DIY Geiger counter projects
✔ Compatible with many custom radiation detector designs
Please note: This listing includes the Geiger tube only. The original box, documentation/manual, and metal protective cover are not included.
Returns are accepted if the item is not as described.
Please contact the seller before opening a return request so we can resolve any issue quickly.
Handling time is 5 days, but usually i ship much faster 1-2 days, as i have all items in stock. Despite the war in Ukraine post works well and all items are delivered quite fast. I am responsible for safe delivery of purchased items, so please buy with confidence.