U this look describe the awkward and sensitive dosimeter that registers slightly beta and gamma vibrations. The SBM-20 type acts as a radiation vibration sensor.
The ring looks like a metal cylinder with a diameter of 12 mm and a length of approximately 113 mm. Its operating voltage is 400 volts. An analogue of the Yomu can be the external sensor ZP1400, ZP1320 or ZP1310.
Description of the robotic dosimeter for the Geiger hospital SBM-20
The dosimeter circuitry is powered by one 1.5 volt battery, so the current flow does not exceed 10 mA. If the operating voltage of the SBM-20 radiation sensor becomes 400 volts, then the voltage is reversed in the voltage reduction circuit, which allows you to increase the voltage from 1.5 to 400 volts. In connection with this, extreme care must be taken when using a well-functioning dosimeter!
The dosimeter's moving switch is nothing more than a simple blocking generator. High voltage pulses appear on the secondary winding (heads 5 - 6) of transformer Tr1 and are rectified by diode VD2. This output is high-frequency, so the pulses are short and have a high transmission frequency.
As the Geiger treatment unit SBM-20 is located in the zone of radiation and sound transmission Light indication Today, the fragments of the offense transistors VT2 and VT3 are closed.
When beta or gamma particles hit the SBM-20 sensor, ionization occurs in the gas located in the middle of the sensor, as a result of which a pulse is created at the output, which reaches transistor booster And in the telephone capsule BF1 there is a clicking sound and the HL1 LED lights up.
The pose is a zone of intense vibration, the light switches off and clicking from the telephone capsule is followed through the skin for 1…2 seconds. This indicates normal, natural radiation.
When the dosimeter is close to any object that may be strongly affected (the scale of the aviation clock or the dial of the old year that lights up), the clicking will become more frequent and may become angry in one the first crackling sound, the HL1 LED will be steadily lit.
So the dosimeter itself and the dial indicator are a microammeter. Use an adjusting resistor to adjust the sensitivity of the display.
Dosimeter details
The Tr1 transformer transformer on the armored core has a diameter of approximately 25 mm. Windings 1-2 and 3-4 are wound with a copper enamel wire with a diameter of 0.25 mm and a total of 45 and 15 turns. The secondary winding 5-6 is wound with a copper wire with a diameter of 0.1 mm, 550 turns.
The LED can be installed AL341, AL307. In the VD2 role, you can install two KD104A diodes by connecting them in series. The KD226 diode can be replaced with KD105V. Transistor VT1 can be replaced on KT630 with any letter, on KT342A. The telephone capsule must be selected with an acoustic coil support of at least 50 ohms. Microammeter with a constant flow of 50 µA.
Whatever we want, radiation has greatly increased in our lives and is not going to go away. We need to learn to live with this, sometimes crimson and careless, phenomenon. Radiation manifests itself in invisible and inaudible effects, and it is impossible to detect them without special devices.
A little about the history of radiation
In 1895, the X-ray industry was open. Through the river, radioactivity was revealed to uranium, also in connection with X-ray changes. They realized that the stench was connected with new, hitherto unknown phenomena of nature. However, the phenomenon of radiation was noted several years earlier, but was not given any significance, although the X-ray measurements were removed by Nikola Tesla and other Edisonian laboratories. Skoda was attributed to health, come what may, but we won’t change it, since we’ve never been alive in such doses. At the beginning of the 20th century, articles began to appear about the harmful effects of radiation on animals. Who was also not given importance to the long story with the “radius girls” - the workers of the factory that produced the one-year-old that was shining. The stench was even wetted by the tip of the tongue. A meager proportion of them were not published for ethical purposes and were lost to the trials of doctors only for the medicinal nerves.
In 1939, the Russian physicist Lise Meitner, who together with Otto Hahn and Fritz Strassmann put the people who first shared the uranium nucleus in the world, casually talked about the possibility of the Lanzug reaction, and from that moment the dance began the reaction of ideas about the creation of a bomb, the bomb itself, and not at all a “peaceful atom”, which the bloodthirsty politicians of the 20th century, obviously, would not have given a penny. Those who were “at the topic” already knew how far the distillation of atomic waste had gone.
How the Geiger-Müller Doctor Appeared
The German physicist Hans Geiger, who worked in the laboratory of Ernst Rutherford, in 1908 introduced the principle of the treatment of “charged particles” as further development already visible ionization chamber, which was electrical capacitor, filling with gas in a small vice. Vaughn was founded by Pierre Curie in 1895 on the fate of the conversion of electric power to gases. Geiger came up with the idea of using gas to identify ionizing agents, which was done by directly injecting gas into the ionization stage.
In 1928, Walter Müller, under the supervision of Geiger, created a set of types of radiation medicines used for the registration of various ionizing particles. The creation of doctors was absolutely necessary, without which it would be impossible to continue the investigation of radioactive materials, since physics as an experimental science is unthinkable without vicinity devices. Geiger and Müller worked directly on the creation of physicians who are sensitive to the skin from the previously discovered types of vibrations: α, β and γ (neutrons have been added since 1932).
The Geiger-Müller detector turned out to be a simple, reliable, cheap and practical radiation sensor. Although it is not the most accurate tool for tracking various types of particles or vibrations, it is rarely suitable as a device for the hidden modification of the intensity of ionizing vibrations. And when combined with other detectors, it is used by physicists for accurate measurements during the course of experiments.
Ionizing and mixing
In order to better understand the work of the Geiger-Müller physician, it is important to note that the statements about ionizing effects have been released. Beyond the significance, before them are those that can cause ionization of speech as it is in a normal state. For which singing energy is needed. For example, radiotherapy or ultraviolet light is not exposed to ionizing effects. The cordon begins with “harsh ultraviolet radiation”, and also “soft x-ray”. This type is a photonic type of reproduction. Photons of great energy are usually called gama quanta.
Ernst Rutherford first divided ionizing chemicals into three types. The whole thing was fragmented at an experimental installation using an additional magnetic field in a vacuum. It's been a long time coming, so:
α - atomic nuclei in helium
β - high energy electrons
γ - gamma quanta (photon)
Later there were openly neutrons. Alpha particles are easily swept away by the primary paper, beta particles are slightly more penetrating, and gamma particles are the most noticeable. The most dangerous neutrons (at a distance of up to tens of meters in the wind!). Due to their electrical neutrality, the stench does not interact with the electronic shells of speech molecules. If the atomic nucleus is lost, the likelihood of it being high is high, leading to instability and disintegration, as a rule, of radioactive isotopes. And yet, with their own strength, disintegrating, they themselves create the entire “bouquet” of ionizing vibrations. The greatest are those that change the object and the living organism itself becomes a source of radiation over many years.
The Geiger-Müller treatment device and the principle of its robot
The Geiger-Müller gas discharge treatment unit is usually built in the form of a sealed tube, glass or metal, from which air is pumped, and instead of adding an inert gas (neon or argon or liquid) with a small vice, with a little halogen or alcohol. A thin thread is stretched along the axis of the tube, and a metal cylinder is moved coaxially behind it. І tube and drain with electrodes: the tube is the cathode, and the drain is the anode. Connect the minus voltage to the cathode steady voltage and to the anode - through a great constant pressure - plus a constant voltage generator. Electrically, there is a voltage distributor, in the middle point of which (the place where the support is connected to the anode of the doctor) the voltage is practically the same as the voltage on the generator. Call it a few hundred volts.
If an ionizing part, an atom of an inert gas, which is in a high-voltage electric field, flows through the tube, a connection with that part is felt. The energy often given during the connection results in the release of electrons from atoms into the gas. Secondary electrons that are created will themselves create new ones, and thus a whole avalanche of electrons and ions will come out. Under the influx of an electric field, the electrons accelerate at the anode, and the positively charged gas ions accelerate to the cathode of the tube. In such a manner, I blame electric strum. If the energy of the fragment has already been spent on the connection, either completely or partially (the fragment has flown through the tube), then the supply of ionized atoms in the gas will end, which is necessary and will be ensured by additional entries, as And we’ll talk when analyzing the parameters of doctors.
When a charged particle enters the Geiger-Müller dispenser, the tube support falls behind the flow tube, and at the same time the voltage at the middle point of the voltage distributor, as it turns out, falls. Then the support of the tube due to the growth of its support is renewed, and the voltage again becomes unchanged. In this way we reject the negative voltage impulse. With important impulses, we can estimate the number of particles that flew by. The strength of the electric field near the anode through such small dimensions is especially high, which makes the doctor sensitive.
Designs of Geiger-Muller treatment units
Current Geiger-Müller medicines are produced in two main versions: “classic” and flat. The classic medicine is made from a thin-walled metal tube with corrugated tubes. The corrugated surface of the dispenser makes the tube rigid, resistant to extreme atmospheric pressure and does not allow it to change under any action. At the ends of the tube there are insulating insulators that are sealed with either thermosetting plastic. They have plugs for connecting to the circuitry of the devices. The tube is sealed and coated with a non-toxic insulating varnish, especially without any damage. The polarity of the pins is also indicated. This is a universal remedy for all types of ionizing agents, especially for beta and gamma.
Physicians, sensitive to mild β-prominence, hesitate differently. Due to the small distance of beta particles, they tend to work flat, with a mica end, which is slightly affected by beta vibration, one of the options for such a treatment is a radiation sensor. BETA-2. All other authorities of doctors are provided with materials, including their preparation.
Therapeutics, used for the registration of gamma vibration, replace the cathode, prepared from metals with a high charge number, or coated with such metals. The gas is badly ionized by gamma photons. Ale gamma photons will knock out a lot of secondary electrons from the cathode, which can be chosen as a source. Geiger-Muller treatment for beta particles is made with thin windows for better penetration of the particles, the fragments contain high-energy electrons, which take up a lot of energy. They interact with the stench of the stench even kindly and quickly waste this energy.
Sometimes the alpha particles have more weight on the right. So, regardless of great energy, on the order of tens of MeV, alpha particles even interact with the molecules that are present, and quickly waste energy. If the river is aligned with the forest, and the electron is aligned with the bag, then the alpha particles will have to be aligned with the tank, which breaks through the forest. However, the average healer responds well to α-viprominion, but not to the extent of up to a few centimeters.
For an objective assessment of the level of ionizing compounds dosimetry At medical clinics in the past, two people often work in parallel with working medical clinics. One is more sensitive to α and β changes, and the other to γ-changes. This scheme for the treatment of two doctors was implemented at the dosimeter RADEX RD1008 and in dosimeter-radiometer RADEX MKS-1009, in which the doctor is installed BETA-2і BETA-2M. At other times, a bar or plate of metal containing cadmium is placed between the healers. When neutrons hit such a bar, γ-vipromining occurs, which is registered. It is important to remove the possibility of meaning from neutron replacement, until such time sorry doctors Geiger is practically insensitive. Another way is to cover the body (cathode) with houses that create sensitivity to neutrons.
Add halogens (chlorine, bromine) to the gas for a quick self-extinguishing discharge. These should also be used in pairs with alcohol, although the alcohol in this case is not very durable (it has a special affinity for alcohol) and the doctor, which “tests”, gradually begins to “jingle”, so that it cannot be processed in the transferred mode. This appears here after registration of 1-9 impulses (billion), which is not so rich. Remedies with halogens are very durable.
Parameters and operating modes of Geiger clinics
Sensitivity of Geiger's physicians.
The sensitivity of the clinician is assessed in relation to the number of micro-roentgens from the visual jet to the emission of pulses. The fragments of the Geiger treatment are not known to vibrate the energy of the particles, an accurate assessment is important. Physicians calibrate gas isotope reactors. This parameter is different types Treatments may be severely affected by setting the parameters of the most advanced Geiger-Müller treatments below:
Geiger-Muller clinic Beta-2- 160 ÷ 240 imp/μR
Geiger-Muller clinic Beta-1- 96 ÷ 144 imp/μR
Geiger-Muller clinic SBM-20- 60 ÷ 75 imp/μR
Geiger-Muller clinic SBM-21- 6.5 ÷ 9.5 imp/μR
Geiger-Muller clinic SBM-10- 9.6 ÷ 10.8 imp/μR
Entrance window area and working area
The area of the radiation sensor through which radioactive particles fly. Characteristics is directly related to the dimensions of the sensor. The larger the area, the more often it is possible to catch the Geiger-Muller treatment. Specify this parameter in square centimeters.
Geiger-Muller clinic Beta-2- 13.8 cm 2
Geiger-Muller clinic Beta-1- 7 cm 2
This voltage indicates approximately the middle of the operating characteristics. The operating characteristic is the flattening of the number of recorded impulses versus voltage, also called a plateau. At this point the greatest fluidity of the robot is achieved (the upper limit between the worlds). The typical value is 400 st.
Width of the operating characteristics of the doctor.
The difference between the voltage of the spark breakdown and the voltage output to the flat part of the characteristic. The typical value is 100 tbsp.
Improved the performance characteristics of the physician.
The effect varies in hundreds depending on the number of pulses per volt. Vin characterizes the statistical loss of extinctions (decrease in the number of impulses). The typical value is 0.15%.
The operating temperature of the treatment unit is permissible.
For patients with cold conditions, the temperature is -50…+70 degrees Celsius. This is an extremely important parameter when the treatment is carried out in chambers, channels and other places of folding equipment: speeders, reactors, etc.
Work resource for a physician.
The number of impulses is limited, as the physician registers the dosage when his indications begin to become incorrect. For adjustments with organic additives, self-extinguishing is usually set to 1e9 (ten at the ninth level or one milliard). The resource is only important in the event that the worker is given enough time to reach the doctor. If the healer is simply saved, this resource is not wasted.
The dead hour of the doctor.
During the entire hour (the hour of renewal), it is the duty of any healer to carry out the flow after treatment of the part that has flown by. The existence of such an hour means that for the frequency of impulses there is an upper limit, and this limits the range of vibrations. The typical value is 1e-4, which is ten microseconds.
It is necessary to take into account that in the dead hour the sensor may appear “off-scale” and fluctuate at the most unsafe moment (for example, a fleeting Lanzug reaction to a virus). Such outbreaks were eliminated, and to combat them, lead screens were installed to cover some of the sensors of emergency alarm systems.
Powerful background of the doctor.
Appears in lead chambers with thick walls for assessing the quality of medical treatment. Typical values are 1...2 pulses per line.
Practical use of Geiger medicines
The Russian and Russian industries produce many types of Geiger-Müller medicines. Splint axle of wider brands: STS-6, SBM-20, SI-1G, SI21G, SI22G, SI34G, “Gamma” series handlers, “Gamma” series end handlers Beta And there are still no others. All of them are used to control the extinction of radiation: at nuclear industry facilities, in scientific and initial deposits, in civil defense, medicine, and life. After the Chernobil accident, daily dosimeters, A previously unknown population behind the name has become even more popular. There were a lot of brands of household dosimeters. The Geiger-Müller doctor itself is used as a radiation sensor. For everyday dosimeters, up to two tubes or end-mounted devices are installed in one tube.
UNITS VIMINARY RADIATION QUANTITIES
For a long time the unit of vimir R (X-ray) was expanded. However, when moving to the CI system, other units appear. X-ray is a unit of exposure dose, the “amount of radiation,” which is expressed by the number of ions that are released in dry air. At a dose of 1 R in 1 cm3, 2.082e9 pairs of ions are created (which corresponds to 1 charge unit of the SGSE). In the CI system, the exposure dose is expressed in coulombs per kilogram, and with x-rays it is related to the following:
1 C/kg = 3876 R
The dose produced is measured in joules per kilogram and is called Gray. This is a replacement for the old unit of radium. The strength of the clay dose disappears in the heat in a second. Exposure dose intensity (EDR), previously measured in roentgens per second, is now measured in amperes per kilogram. The equivalent dose of vipromine, when the dose is 1 Gy (Gy) and the coefficient of vipromine is 1, is called Sievert. Ber (biological equivalent of an x-ray) is one hundredth part of a sievert, which is now considered obsolete. Tim is no less, and today all the old units are actively stagnating.
The main concepts in radiation worlds are dose and pressure. The dose is the number of elementary charges in the process of ionization of speech, and the intensity is the speed of the dose administered in one hour. And yet in some cases it is expressed that there is relish and handiness.
However, the minimum dose is not safe to remove damage to the body. It’s not easy for Rozrakhunok to finish it. For example, your dosimeter shows 300 milli-roentgen per year. If you run out of money here, you take a dose of 24 * 0.3 = 7.2 roentgens. It’s not safe and you need to get out as soon as possible. Those who have detected weak radiation need to go out of it and check it at the station. If I'm coming for you, you can be greeted, you were lost under neutrons. But no skin dosimeter can react to them.
For radiation, a value that characterizes the number of disintegrations per hour is called the activity and viability of several different units: curies, becquerels, rutherfords, and others. The amount of activity measured at sufficient intervals over the hour, as it changes, allows the hour to be expanded, according to the law of radioactive decay, if it becomes necessary to remain safe.
In connection with the environmental heritage of human activity associated with nuclear energy, as well as industry (called military), which contains radioactive compounds as a component or the basis of its products, The fundamentals of radiation safety and radiation dosimetry are becoming a hot topic today. The cream of natural ionizing agents interacts with skin cancer and is more likely to be a place contaminated by radiation due to human activity. Thus, in order to protect your health and the health of your loved ones, it is necessary to know the level of infection of this and other objects and objects. Who can use a dosimeter - a device for varying the effective dose or the intensity of the ionizing dose over a period of time.
First start before preparation (or purchase) I'll add it for now It is necessary to make statements about the nature of the parameter that is being simulated. Ionizing vibration (radiation) is the flow of photons, elementary particles or structures under atoms, which ionize the substance. Divided into several types. Alpha viprominyuvannya There is a flow of alpha particles - helium-4 nuclei, alpha particles, which are generated during radioactive decay, can be easily absorbed by an arctic paper, which is a concern mainly when the middle of the body is damaged. Beta-viprominyuvannya- due to the flow of electrons that occur during beta decay, to protect from beta frequencies with energy up to 1 MeV, add a few millimeters to the aluminum plate. Gamma-viprominuvannya It has a much more penetrating effect, the fragments consist of high-energy photons that do not carry a charge, for the protection of effective important elements (lead, etc.) with a ball of a few centimeters. The pervasiveness of all types of ionizing vibration lies in energy.
For the registration of ionizing vibration, it is important to use Geiger-Müller medicines. This simple and effective device consists of a metal cylinder of metal or metal fusion in the middle and a thin metal thread stretched along the axis of this cylinder, the cylinder itself is filled with diluted gas. The operating principle is based on impact ionization. When ionizing liquid hits the walls of the dispenser, the electrons are knocked out, the electrons collapsing with the gas and combine with the atoms of the gas, the electrons are knocked out of the atoms and create positive ions. electronics The electric field between the cathode and anode accelerates the electrons to energies at which impact ionization begins. An avalanche of ions begins to arise, leading to the proliferation of the first plants. When the field strength is high, the energy of these ions becomes sufficient to generate second avalanches, thereby supporting a self-sustaining discharge, and as a result, the flow through the doctor sharply increases.
Not all Geiger physicians can detect all types of ionizing radiation. Basically, they are sensitive to one vibration - alpha, beta or gamma vibration, but often can also register other vibrations. So, for example, the Geiger SI-8B is used for recording soft beta vibration (so, due to the energy of the particles, vibration can be divided on the pulp and crust), prote Denmark sensor So the very singing world is sensitive to alpha vibration and to gamma vibration.
However, approaching the design of the statistics, our goal is to create the most simple, naturally portable, Geiger doctor or, more accurately, a dosimeter. To prepare this device, I decided to get an SBM-20. This Geiger doctor is used for registration of hard beta and gamma viprominion. Like most other medical devices, the SBM-20 operates at a voltage of 400 volts.
The main characteristics of the Geiger-Muller SBM-20 physician (table from the guide):
This physician has a remarkably low level of accuracy in the reduction of ionizing stimulation, but is not sufficient to exceed the permissible dose for humans. SBM-20 is used in many commercial dosimeters. To enhance the indicators, often vicorize a series of tubes. And to increase the accuracy of gamma-vipromining dosimeters, the dosimeter is equipped with beta-vipromining filters, in which case the dosimeter registers only gamma-vipromining, and thus delivers accurately.
When the dose of radiation is low, it is necessary to take into account certain factors that may be important. Please note that the ionizing and ionizing generators of the Geiger treatment unit are available in a series of pulses. This is the name of the physician. This also includes a number of factors: radioactive contamination of the materials of the treatment device itself, spontaneous emission of electrons from the cathode of the treatment device and cosmic vibration. All it takes is a handful of “stirring” impulses per hour.
Also, a diagram of a simple dosimeter based on the Geiger SBM-20 physician:
I assemble the circuit on a breadboard:
The circuit does not contain any scarce parts (except, of course, the doctor himself) and does not contain any programming elements (microcontrollers), so that the circuit can be assembled in a short time without any special difficulties. However, such a dosimeter does not move the scale and it is necessary to calculate the dose of radiation by ear clicking. Such a classic option. The circuit consists of a voltage switch of 9 volts - 400 volts.
On the NE555 microcircuit there is a multivibrator, the frequency of which is approximately 14 kHz. To increase the operating frequency, you can change the value of resistor R1 to approximately 2.7 kOhm. It will be interesting if you select the throttle (and possibly prepare it) and you will see a squeak - as the frequency increases, the squeak will not be heard. Choke L1 is required with a rating of 1000 - 4000 µH. The best way to find the power supply is for a burnt-out energy-saving light bulb. Such a throttle and stagnation in the circuit, in the photo, are more likely to be wound on the core, which is necessary for use in the production of pulse transformers. Transistor T1 can be used in any other n-channel field with a drain-turn voltage of at least 400 volts, and usually more. Such a conversion will give every few milliamperes of power at a voltage of 400 volts, but for the Geiger robot you can't beat a lot of times. After switching on the life from the circuits on the charged capacitor C3, the circuit operates for approximately 20-30 seconds, due to its low capacity. The VD2 suppressor limits the voltage to approximately 400 volts. Capacitor C3 must be used at a voltage of at least 400 - 450 volts.
Like Ls1 you can select either a speaker or a speaker. In the event of ionizing vibration, the flow does not flow through resistors R2 – R4 (in the photo there are five resistors on the breadboard, and their lower support represents the circuit). As soon as the Geiger treatment is applied to a similar part in the middle of the sensor, ionization of the gas occurs and its support changes sharply as a result of which the pulse of the stream is generated. Capacitor C4 absorbs the constant part and transmits only a pulse to the speaker. I feel like there's a clicking sound.
In my opinion, as a result of life, there are two rechargeable batteries from old phones (two, because the power supply must be more than 5.5 volts to run the robotic circuit through the assembled element base).
Well, the circuit works, it clicks occasionally. Now yak tse vikoristati. The simplest option is to click little bits - everything is good, it clicks often or it starts burning incessantly - it’s bad. Another option is that it is approximately equivalent to the number of pulses per hour and translates into the number of clicks in microR/year. For this example, it is necessary to take the Geiger sensitivity value. However, different numbers always have different numbers. Ideally, it is necessary to carry out laboratory tests for the selected Geiger treatment with standard vipromining devices. So for SBM-20, the sensitivity values vary between 60 and 78 imp/mR for different devices and indicators. So, the number of pulses was measured in one pulse, then the number is multiplied by 60 to approximate the number of pulses in one year and all divided by the sensitivity of the sensor, then by 60 or 78 or whatever is closer to your action information comes out and, as a result, the value is taken away from microR/year. For a reliable value, it is necessary to generate a number of extinctions and take the arithmetic mean of the values between them. The upper limit of the safe level of radiation becomes approximately 20 – 25 microR/year. Acceptable rhubarb become approximately 50 µR/h. Numbers may vary in different countries.
P.S. At the same time, I drew attention to the article about the concentration of radon gas that penetrates into buildings, water, and so on. in different regions of the country and Dzherel.
List of radio elements
| Appointment | Type | Denomination | Quantity | Note | Shop | My notebook |
|---|---|---|---|---|---|---|
| IC1 | Programming timer and oscillator | NE555 | 1 | Before the notepad | ||
| T1 | MOSFET transistor | IRF710 | 1 | Before the notepad | ||
| VD1 | Direct diode | 1N4007 | 1 | Before the notepad | ||
| VD2 | Drying Diode | 1V5KE400CA | 1 | Before the notepad | ||
| C1, C2 | Capacitor | 10 nF | 2 | Before the notepad | ||
| C3 | Electrolytic capacitor | 2.7 µF | 1 | Before the notepad | ||
| C4 | Capacitor | 100 nF | 1 | 400V |
Everyday dosimeters manufactured in Russia and other SND countries occupy leading positions in the light market, so only such devices were selected for the editorial test. The stench was tested in laboratory sinks (alpha-, beta- and gamma-gerel), as well as in one place for radioactive contamination (radio-226, 0.92 μSv/year) and in household sinks (potassium dobrova, welding electrodes with the addition of torus Iyu ) and ionization sensors dim). To control the vicoristics, use the Exploranium GR-130 gamma spectrometer. All dosimeters showed a range of gamma-viprominion (soft cream) at the intervals of passport suppression, and for other types of prominence, the differences were the same. Most of the dosimeters that are being tested are based on the classic Geiger-Müller medicinal device SBM-20 manufactured by Elektrokhimprylad. Unfortunately, his sensitivity deprives most of the beauty, and for the low levels of radiation of the panthers, a bunch of quills are torn. For dosimeters the size of a wrist watch, the SBM-21 doctor is used, which is even less sensitive (about 10 times). More thorough dosimeters are used by end physicians. Our test used a dosimeter with such a Beta-1 type treatment unit manufactured by the Consensus company, which is approximately twice as sensitive to gamma-vibration, lower SBM-20, and even more expensive.
Radex RD1503+
Sensor: SBM-20 without filter. Vimiryuvannya: Depends on low-energy readings of gamma-prominence and mixed gamma-beta propagation. On some jerels, the fit went off scale - the upper limit of the range has the fewest test participants. The natural background depends on the second time. To search for small spots of infection, it is best to approach through the low sensitivity of the sensor. Visnovki: the device has a friendly interface; It will be frustrating to sometimes be unmotivated to restart the recovery cycle, which may delay obtaining accurate results.
Radex RD1706
Sensor: 2xSBM-20 without filters. Vimiryuvannya: Depends on the indications with mild gamma-promotion and mixed gamma-beta stimulation. Depends on nature approximately once again. For the detection of small stains, contamination is not ideal, but it is suitable: two sensors speed up its reaction to a change in the level of radiation. Visnovki: Receiving interface plus high-speed dialing. In addition, this device is much less flexible to the point of unmotivated restarting.
Soex-01M
Sensor: SBM-20 without filter. Vimiryuvannya: depends on the indications with mixed gamma-beta stimulation. Depends on nature approximately once again. To search for small spots of infection, it is best to approach through the low sensitivity of the sensor. Visnovki: very compact, lightweight, with a colorful display and the ability to connect to a computer via USB. The palette of colors and fonts always ensures easy readability. Displays a clear assessment of the level of the background and changes the display diagram over the hour. As soon as the manufacturer updates the firmware, it removes unnecessary animation when starting the program, optimizes colors and fonts for better readability, resulting in one of the most common everyday devices.
MKS-05 Terra-P
Sensor: SBM-20 with filter. Vimiryuvannya: with the promise not to go beyond the passport theft of the high-grade filter Terra-P allows you to carry out approximately the intensity of the flow of beta-viprominion of the hard. The natural background depends on the second time. To search for small spots of infection, it is best to approach through the low sensitivity of the sensor. Visnovki: The device appears to be suitable for floor use, and not just gentle household use. The filter really matches the accuracy and ease of adjustment. Unfortunately, the device does not remember the adjustment of the alarm threshold and reduces it by 0.3 µSv/year.
Belvar RKS-107
Sensor: 2xSBM-20 with filters. Vimiryuvannya: The vibration of cesium-137 is definitely dying out, but the gamma-vipromotion is likely to occur a second time. The advanced mode of vibrating the thickness of the beta-frequency flow allows you not to interfere with the usual approximate coefficients of overconversion. Depends on the repeater for a more natural time. To search for signs of infection, it is extremely inaccessible, since it is not possible to carry out viming without interruption and does not record the particles. Visnovki: Suvory decline of the Radyansky past. This device does not mean anything other than how to capture the number of impulses for singing hour. All mathematical processing is carried out without any hassles by koristuvachev, vikorystov and papier. On the other hand, without registering with the registry, a device must undergo individual testing, and then stand as a basic everyday dosimeter.
DP-5V
Sensor: SBM-20 for the suppression of advanced, medium and high levels of radiation, SI3BG for the suppression of high levels of radiation. Equipped with a filter and control device based on strontium-90. Vimiryuvannya: at less than 0.5 μSv/year, the needle oscillates significantly, making it difficult to fade. At high levels Radiation readings are generally stable over a wide range of gamma energy levels. The low sensitivity of the sensor is often compensated by its placement on the pants, which makes it easier to detect radiation emissions using the DP-5 than most other test participants. Visnovki: Viyskova, and besides, there is also the savagery of the Radyansky past. In some cases, such an accessory can be purchased for a symbolic price. It is more likely an item for a collection or a prop.
Polimaster DKG-RM1603A
Sensor: SBM-21 without filter. Vimiryuvannya: When gamma vibration is measured, the dosimeter depends approximately twice. Not sensitive to beta vibration. I depend on the natural rate of radiation for about a quarter. It is possible to detect local obstruction only sporadically - the device reacts to changes in the level of radiation quite strongly. Visnovki: The reaction of changing the strength of the dose can no longer be suppressed.
SNDIP Aunis MKS-01SA1M
Sensor Cabin: end treatment unit Beta-1, particulate filter. Vimiryuvannya: The only participant in the test was found to be able to adequately moderate the density of the flow of beta frequencies from cesium-137 and dampen the density of the flow of alpha frequencies. Depends on the natural flow of radiation approximately a second time. However, a sensor that is sensitive to gamma and especially beta vibration is the most suitable device for detecting radioactive flames. Visnovki: Definitely the coolest accessory. There is a very simple indicator system for statistical loss with continuous refinement of the result.
In this article you will find a description of simple dosimeter circuits on the SBM-20 hospital, which can provide sufficient sensitivity and register the smallest values of beta and gamma radioactive particles. The dosimeter circuit is based on a commercial radiation sensor of the SBM-20 type. It is similar to a metal cylinder with a diameter of 12 mm and a length of approximately 113 mm. At times of need, it can be replaced with ZP1400, ZP1320 or ZP1310.
A simple diagram of a dosimeter on SBM-20 |
The design is powered by up to one AA battery. Apparently, the operating voltage of the SBM-20400 volt sensor is due to the need to reverse the voltage.
Promotes re-creation of viconics based on a simple blocking generator. High-voltage pulses from the secondary winding of the transformer are rectified by a high-frequency diode.
If the SBM-20 physician removes the zone of radiation damage, the transistors VT2 and VT3 are closed. The sound and light alarm is not active. As people in the hospital consume radioactive particles, the gas located in the middle of the sensor is ionized, and at its output is a pulse that passes to the transistor booster and a clicking sound is heard in the telephone speaker And the LED lights up.
At weak natural radiation intensity, the light flashes and clicking are repeated every 1...2 seconds. There is no need to talk about normal background radiation. As the level of radioactivity increases, the clicking sound will become more frequent and, at critical values, turn into one continuous crackling sound, and the LED will gradually darken.
Since the radio amplifier structure contains a microammeter, an adjustable support can be used to adjust the sensitivity of the reading.
The transformer for converting the armor from the armor core has a diameter of 25 mm. Windings 1-2 and 3-4 with a copper core with a diameter of 0.25 mm consist of 45 and 15 turns. The secondary winding is also made of copper wire, with a diameter of 0.1 mm - 550 turns.
Simple design radioactivity doctor on SBM-20 option 2 |
The dosimeter sensor is a Geiger SBM20. The blocking generator generates a high voltage on the anode - from the winding of the transformer, which moves the pulses through the diodes VD1, VD2 and charges the filter capacitance C1. Operation R1 is based on the doctor’s needs.
The oscillator on elements DD1.1, DD1.2, СЗ and R4, transforms the impulses that go from the Geiger doctor and causes a prolonged decline, direct. On elements DD1.3, DD1.4, C4 and R5, a fragmented generator audio frequency. Threshold boost, collected on DD2 microcircuits.
Depending on the frequency of passage of pulses from the Geiger doctor, keep the voltage at capacity C9; Once it reaches the level of voltage of the transistor that enters DD2, the HL1 light-emitting diode lights up, the frequency of which increases due to the increase in radiation quanta that is lost to the sensor.
Transformer T1 is prepared with your own hands on a ring core M3000NM K16x10x4.5 mm. The primary winding contains 420 turns of PEV-2-0.07 dart. The secondary winding consists of 8 turns with a diameter of 0.15...0.2 mm; the third winding is 3 turns using the dart itself.