Instruction Manual for the RS-70 Contamination Alarm Page 2: Table of Contents (Translated) 1 - General Information 2 - Technical Data 3 - Principle of Operation 4 - Device Description 5 - Operating Instructions 6 - Transport and Storage 7 - Packaging 8 - Included Accessories 9 - Acceptance and Delivery Conditions 10 - Warranty 11 - Annex 1 – Characteristics of the DOB-51 Tube 12 - Annex 2 – Internal Structure of the RS-70 Page 3: General Information The RS-70 contamination alarm is designed to detect and signal the presence of ionizing radiation — specifically gamma radiation — in the event of contamination from radioactive fallout. The device is intended for use by civil defense units, emergency response teams, and institutions dealing with radiological hazards. The RS-70 operates in three dose-rate threshold modes: - 0.5 R/h - 5 R/h - 30 R/h When the preset dose rate is exceeded, the alarm activates using both visual (red indicator light) and audible (buzzer) signals. Page 4: Technical Data Parameter Value Type of radiation detected Gamma Threshold values 0.5 / 5 / 30 R/h Alarm indication Optical and acoustic Power source 4 × R20 batteries or external 4.5–7V Operating voltage range 3.6 V – 6.5 V Operating time (non-alarm) min. 200 h (avg. 300 h) Operating time (alarm) min. 50 h (avg. 80 h) Weight (with batteries) Approx. 1.7 kg Detector DOB-51 Geiger-Müller tube Working temperature range −30°C to +50°C Relative humidity Up to 98% Page 5: Principle of Operation The RS-70 contamination alarm works by continuously measuring the level of ionizing radiation in the surrounding environment. Detection is based on the ionization effect of gamma radiation on a Geiger-Müller counter (type DOB-51). When gamma radiation passes through the detector, it ionizes the gas inside the tube, generating electrical pulses. These are processed by the electronic circuitry inside the RS-70. If the number of pulses per unit time exceeds the preset threshold corresponding to a dose rate of 0.5 R/h, 5 R/h, or 30 R/h, the device activates an alarm signal. The RS-70 does not display the actual dose rate but simply indicates when a preset threshold has been exceeded. Page 6: Device Description The RS-70 consists of the following primary components: Geiger-Müller Detector (DOB-51): A cylindrical, sealed glass tube filled with a gas mixture. It is mounted in a radiation-shielding compartment inside the device. Pulse Processing Circuit: Amplifies and shapes the signals from the detector for analysis. Threshold Comparator and Alarm Circuit: Continuously compares pulse rate to the selected threshold. If exceeded, triggers the red light and acoustic signal. Power Supply System: Provides high voltage (approx. 400 V) for the detector, derived from batteries or external source. Control Panel: Located on the top of the unit. Includes: - Threshold selection switch - Test button - Battery check indicator - Alarm indicators Page 7: Operating Instructions Powering On the Device Insert 4 R20 batteries into the compartment, ensuring correct polarity. Alternatively, connect an external power supply (4.5–7 V DC). Selecting Alarm Threshold Use the rotary switch to set the desired threshold: - “0.5” for 0.5 R/h - “5” for 5 R/h - “30” for 30 R/h Self-Test Procedure Press the test button. This simulates a radiation signal, activating the alarm. - A functioning alarm will produce both light and sound. - No signal indicates malfunction — check battery or internal circuits. Battery Check Press the battery test button. The green LED should light. - If not, replace batteries or check power supply. Operation During Use Once switched on, the device continuously monitors radiation. If the selected dose threshold is exceeded, the red LED and buzzer activate. Resetting the Alarm The alarm remains active as long as radiation stays above the threshold. Lower radiation or turning the device off will silence it. Page 8: Transport and Storage - The RS-70 should be transported in its original protective packaging. - During transport, ensure the device is protected from mechanical shocks, moisture, and strong vibrations. - Storage conditions: - Temperature range: −50°C to +60°C - Relative humidity: ≤98% at 35°C - If stored for long periods, remove the batteries to avoid leakage or corrosion. - Store the unit in a clean, dry, and dust-free environment. Page 9: Packaging - The RS-70 is delivered in a sealed transport case which contains: - The RS-70 radiation alarm - 4 × R20 batteries (if included) - User instruction manual (Polish) - Set of spare fuses (if applicable) - Certificate of acceptance/inspection (if provided) - Packaging ensures the device is ready for immediate use after unpacking and inserting batteries. Page 10: Accessories Supplied Depending on the production series, the following may be included: - Shoulder strap or carrying handle - Protective shielding cap for the detector compartment - External power cable (for connection to 6V field power) - Service instruction leaflet All accessories should be accounted for during receipt and periodically inventoried. Page 11: Conditions of Acceptance and Delivery The RS-70 is accepted for service if it meets the following conditions: - Passes the self-test (alarm and power indicators work) - Detector produces pulses when exposed to test radiation - No physical damage or corrosion is observed - Accompanied by valid acceptance documentation (if applicable) The buyer has the right to reject the device if any conditions are not met. Claims must be made within the warranty period and in accordance with the manufacturer's terms. Page 12: Warranty The RS-70 is covered by a 12-month warranty from the date of delivery to the end user. Warranty does not apply in cases of: - Mechanical damage - Tampering with internal components Operation outside specified environmental conditions - Damage caused by battery leakage Repair or replacement under warranty is carried out by authorized service centers only. Annex 1: Characteristics of the DOB-51 Geiger-Müller Tube Parameter Value Tube type DOB-51 Operating voltage 380–420 V Typical working voltage ~400 V Radiation type sensitivity Gamma Dead time 190 µs Sensitivity at 0.5 R/h ≥ 1200 pulses per second Physical dimensions Length: 70 mm, Ø10 mm Fill gas Halogen/quenching mix Operating temperature range −40°C to +50°C Note: Some units may be equipped with a DOB-50 tube with similar characteristics. Annex 2: Internal Construction of the RS-70 This section includes a basic wiring diagram (not reproduced here) and component layout showing: - Geiger-Müller tube mounted centrally in a shielded compartment - High-voltage power section using transistor inverter - Comparator circuitry with threshold adjustment - Visual and acoustic signaling modules - Battery and external power input with protection diodes - Test circuit simulating radiation event via artificial pulse injection For technical servicing, refer to the manufacturer’s extended service manual.