STS-5

The STS-5 (СТС-5 rus.) is an original Soviet Geiger-Müller tube, designed for detecting beta (β) and gamma (γ) radiation. Produced in the USSR from the 1960s through the 1980s, it was widely used in military defense dosimeters, as well as in portable radiation meters.

STS-5 is equivalent to SBM-20-1, SBM-20, SI22G

Technical specifications:

• Type: Halogen-quenched Geiger-Muller tube
• Operating voltage range: 380–460V
• Recommended operating voltage: ~400V
• Working current: ≤ 0.3mA
• Plateau length: ≥ 80V
• Plateau slope: ≤ 0.25%/V
• Gamma sensitivity: ~75 CPM per µR/h (Co-60 reference)
• Dead time: ~190µs
• Background count rate: ≤ 60CPM
• Radiation types detected: Beta (≥ 0.25MeV), Gamma (≥ 30keV)
• Dimensions: 110 mm (length) × 12 mm (diameter)
• Weight: ~10 g
• Cathode material: Metal cylindrical body
• Anode: Fine axial wire
• Filling gas: Halogen mixture (quenching agent)
• Lead configuration: Axial wire contacts

The STS-5 is the Soviet counterpart to the well-known SBM-20, offering nearly identical specifications. Its rugged metal housing, low background count, and stable plateau make it reliable even after decades of storage.

Perfect for:

• DIY Geiger counter projects
• Replacement in vintage Soviet dosimeters
• Laboratory experiments and radiation detection courses
• Collectors of Cold War–era electronics

Each tube is tested before shipping to ensure proper operation.