Radiation hazard indicator. Scheme, description

Free technical library

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Schemes of radio-electronic and electrical devices

Radiation hazard indicator. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Dosimeters

Comments on the article

At present, when restrictions on the use of radiation hazard control devices have been lifted, the problem of their manufacture becomes very relevant. The industry is just starting to mass-produce dosimeters, and people, especially children living in a disaster area, need such checks every day.

The radiation hazard indicator (RHI) offered to the attention of readers is easy to manufacture and operate. Devices of this type are not subject to verification by the State Standard and can be recommended for widespread use. The disadvantage of the IRO is that it can be powered only from the mains. However, for a day, a person stays in a room for about 10-12 hours, where sockets are always at hand.

The radiation hazard indicator (RHI) is designed to signal (by increasing the number of flashes of a neon lamp) the excess of the natural radiation background or contamination of soil, food, and water with radionuclides. Moreover, RES also reacts to the natural radiation background, which is very convenient for checking the device's performance.

Power is supplied from the AC mains with a voltage of 220 V. For the operation of the ionization sensor, a voltage doubling circuit is used on semiconductor diodes VD1, VD2 (Fig. 1) and capacitors C1, C2. The ionization sensor is connected to the doubling circuit through resistor R2. Resistors R1 and R4 provide the necessary output voltages. For simplicity, the device does not contain a high voltage stabilizer.

Ris.1

When a particle enters the sensor, the gas ionizes and current flows through the sensor. The damping of the pulse is carried out by the sensor itself. The pulses from the sensor are fed to the transistor VT1. A neon lamp HG1 is connected to its collector circuit through a resistor R3, which limits the collector current. The transistor is powered by a half-wave rectifier VD2, C2.

The device is designed to use various sensors with an operating voltage of 360-540 V.

The indicator uses widely used details. Diodes VD1, VD2 type KD102, capacitors C1 and C2, respectively, MBM and K73-11, resistors-MLT-0,5. The transistor can be of the brand KT605A, KT605B or KT605BM.

It is permissible to use IN-6, TN-0,2, etc. as a neon indicator. Ionization sensor type SBM-21, SBM-11, but SBM-20, STS-20, STS-5 can also be used the dimensions of the device will increase).

Structurally, the indicator is designed in a plastic case of suitable dimensions. Opposite the ionization sensor there is a rectangular hole covered with polyethylene 0,2-0,3 mm thick. The device is connected to the electrical network using a stranded wire with a power plug, but it is also possible to refuse to use the wire by fixing the power plug (or part of it) on a plastic case.

The performance of the device is established by individual flashes of a neon lamp, indicating a natural radiation background. If the object under study (soil, food) contains radionuclides, the frequency of indicator flashes increases.

In conclusion, we note an interesting feature of the device: when it is brought to potash fertilizers (KCl), an increase in the frequency of outbreaks is observed. This indicates a high sensitivity of the indicator, the ability to respond even to weak K40 radiation, which is included in fertilizers in small quantities.

Particular attention should be paid to compliance with the rules of electrical safety in the manufacture and establishment of RES. The indicator is powered by 220 V, so all work with the device should be carried out with the case closed. Especially carefully it is necessary to isolate the mains input, as well as the places where the supply wires are attached to the housing.

Capacitors C1, C2 must be designed for a voltage of 400-630 V (when the device is disconnected from the mains, they are automatically discharged through resistors R1, R3, R4). It is strictly forbidden to operate the device with a shorted fuse FU1, at high ambient humidity, if moisture gets inside the case.

The IRO housing (Fig. 2) is made of polystyrene 1,5 mm thick. Hull parts are glued with "Supercement" or any other suitable glue. A rectangular hole 90x10 mm in size was made along the diagonal of the upper plate, closed with a polyethylene lining 100x15 mm in size, 0,1-0,3 mm thick, fixed with Moment glue. A hole D = 4 mm for a power cord was drilled on the left wall (wire cross section 0,35-0,75 mm2). On the right wall there is a hole D = 8 mm for a neon lamp. On the upper part of the case, the name "IRO" is made in a translated font; next to the network input - "220 V".

Ris.2

The layout of the parts in the case is shown in Figure 3. Mounting - using caps D = 0,7-1,5 mm, which are inserted into the holes of the board made of fiberglass 0,7-2 mm thick.

Ris.3

Connections of parts are made with a mounting wire with a cross section of 0,2-0,3 mm2 in PVC insulation.

The sensor is fixed with pieces of tinned wire D=0,8-1 mm by soldering.

After mounting and checking the operation of the device, the upper part of the housing must be glued with any glue.

Author: V. Kubyshkin

See other articles Section Dosimeters.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

The world's tallest astronomical observatory opened 04.05.2024

Exploring space and its mysteries is a task that attracts the attention of astronomers from all over the world. In the fresh air of the high mountains, far from city light pollution, the stars and planets reveal their secrets with greater clarity. A new page is opening in the history of astronomy with the opening of the world's highest astronomical observatory - the Atacama Observatory of the University of Tokyo. The Atacama Observatory, located at an altitude of 5640 meters above sea level, opens up new opportunities for astronomers in the study of space. This site has become the highest location for a ground-based telescope, providing researchers with a unique tool for studying infrared waves in the Universe. Although the high altitude location provides clearer skies and less interference from the atmosphere, building an observatory on a high mountain poses enormous difficulties and challenges. However, despite the difficulties, the new observatory opens up broad research prospects for astronomers. ... >>

Controlling objects using air currents 04.05.2024

The development of robotics continues to open up new prospects for us in the field of automation and control of various objects. Recently, Finnish scientists presented an innovative approach to controlling humanoid robots using air currents. This method promises to revolutionize the way objects are manipulated and open new horizons in the field of robotics. The idea of controlling objects using air currents is not new, but until recently, implementing such concepts remained a challenge. Finnish researchers have developed an innovative method that allows robots to manipulate objects using special air jets as "air fingers". The air flow control algorithm, developed by a team of specialists, is based on a thorough study of the movement of objects in the air flow. The air jet control system, carried out using special motors, allows you to direct objects without resorting to physical ... >>

Purebred dogs get sick no more often than purebred dogs 03.05.2024

Caring for the health of our pets is an important aspect of the life of every dog owner. However, there is a common assumption that purebred dogs are more susceptible to diseases compared to mixed dogs. New research led by researchers at the Texas School of Veterinary Medicine and Biomedical Sciences brings new perspective to this question. A study conducted by the Dog Aging Project (DAP) of more than 27 companion dogs found that purebred and mixed dogs were generally equally likely to experience various diseases. Although some breeds may be more susceptible to certain diseases, the overall diagnosis rate is virtually the same between both groups. The Dog Aging Project's chief veterinarian, Dr. Keith Creevy, notes that there are several well-known diseases that are more common in certain breeds of dogs, which supports the notion that purebred dogs are more susceptible to disease. ... >>

Random news from the Archive

APED3820PBC Blue LED 18.02.2004

KINGBRIGHT's APED3820PBC blue surface mount LED is launched with a wide arc (60°x35°) and dimensions of 3,8x2,0x3,2mm.

With an operating current of 20 mA, the brightness of the LED is 150 mcd.

Other interesting news:

▪ Luminous target of the surgeon

▪ The main reason for the love of alcohol discovered

▪ Scientists have learned to erase memories

▪ Samsung is going to release a mobile phone with a built-in satellite TV

▪ Wheel instead of gateway

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Life of remarkable physicists. Article selection

▪ article Investigation and analysis of industrial accidents (registration and accounting). Fundamentals of safe life

▪ article How are the Rostov streets Vertical and Horizontal located relative to each other? Detailed answer

▪ article Expander driver (expanding line operator). Standard instruction on labor protection

▪ article Automatic staircase lighting control with motion sensor. Encyclopedia of radio electronics and electrical engineering

▪ article Map-traveler. Focus Secret

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews