Control circuit of radon measuring instrument

Abstract

The invention belongs to the technical field of radon measuring instruments, and discloses a control circuit of a radon measuring instrument. The problem that an existing calibration method consumes alarge amount of time, manpower and material resources is solved. The control circuit is mainly characterized by comprising a high-voltage circuit for adjusting a photomultiplier (PMT), a signal filtering circuit for processing a nuclear pulse signal, and a counting circuit for counting the nuclear pulse signal, the counting circuit is connected with the signal filtering circuit, the radon measuring instrument control circuit comprises a single chip microcomputer control circuit connected with the signal filtering circuit, and the single chip microcomputer control circuit obtains a peak valueof the nuclear pulse signal through a program algorithm, converts the peak value into an energy spectrum signal and displays the energy spectrum signal on a display screen or a display interface; andthe single-chip microcomputer control circuit adopts a single-chip microcomputer with AD and DA functions. During calibration, the influence of external environment temperature and humidity changes oncalibration can be overcome, the calibration accuracy and consistency are enhanced, and the instrument debugging time is saved.

Description

technical field [0001] The invention belongs to the technical field of a radon measuring instrument and its standards, and in particular relates to a control circuit of a radon measuring instrument. Background technique [0002] Harmful gases in the air are the main factors that damage human health. With the improvement of people's living standards, people pay more and more attention to whether the content of radon in the air, especially in indoor air, meets the national standards. The measurement of the content of radon in the air has become a problem that people are more concerned about, and the country has also issued a corresponding detection standard for this purpose - "GB / T14582-1993 Standard Measurement Method for Radon in Ambient Air". At present, the mainstream radon measurement methods include ionization chamber method, scintillation chamber method, double filter membrane method, activated carbon method, etc., and scintillation chamber method is widely used in my c...

AI Technical Summary

Problems solved by technology

However, this method will consume a lot of time due to the need for multiple measurements, and each photomultiplier tube is affected by the material and processing technology, and the optimal amplification area has certain randomness, so every radon meter needs to use this method. Parameter debugging consumes a lot of time, manpower and material resources in the actual production process

[0006] In the threshold debugging process, in order to prevent the noise signal from exceeding the threshold and being mistakenly counted as a nuclear pulse signal, the threshold is usually raised as much as possible while ensuring the detection efficiency. Since there is no clear reference data, it is usually only possible to rely on experience. Measure to find an approximately suitable value. This rough adjustment method will cause some nuclear pulse signals with weak energy to be missed, making the measurement inaccurate and the measurement efficiency low.

[0007] To sum up, the existing parameter debugging methods for radon detectors are complex, time-consuming, and poor in accuracy.

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