An open-type Franck-Hertz experimental instrument and method

Abstract

The present invention relates to an open Franch-Hertz experimental instrument and method, comprising a signal generator, a digital oscilloscope, a DC power supply, and an open Franch-Hertz experimental setup. The open Franch-Hertz experimental setup is composed of discrete functional modules, including an argon-filled electron tube, a vacuum electron tube, an operational amplifier, a low-pass filter circuit, an instrumentation amplifier, a nanoampere ammeter, a potentiometer, and a battery. The Franch-Hertz experimental instrument provided by the present invention features an open structure, free combination of functional modules, and strong hands-on practicality. It also offers a wide range of parameter adjustments, enabling novel experimental results, rich research content, and a strong sense of free exploration.

Description

Technical Field

[0001] The invention relates to a university physics experiment teaching instrument, in particular to an argon atom Franck-Hertz experiment instrument and method. Background Art

[0002] In 1914, German physicists J. Frank and G. Hertz discovered that the electron flow in a mercury-filled Franck-Hertz tube exhibited periodic changes as the energy of the accelerated electrons increased while studying the interaction between low-energy electrons and atoms in discharge phenomena, providing direct experimental evidence for the atomic energy level model. The collision between electrons and atoms occurs in the Franck-Hertz tube, and its structure is as follows: Figure 1 (Left) As shown. Taking argon atoms as an example, electrons are emitted from cathode K. An electric field is applied between K and grid G to accelerate the electrons. There is a reverse repulsion voltage between G and screen P. When the electrons pass through the KG space and enter the GP space, if they still have a large amount of energy, they can rush through the repulsion electric field and reach screen P, becoming a current passing through the galvanometer. If the electrons collide with atoms in the KG space and give part of their energy to the atoms, causing the latter to be excited, the remaining energy of the electrons may be very small, so that after passing through grid G, it is not enough to overcome the reverse repulsion voltage, and cannot reach screen P, and therefore does not flow through the galvanometer. If many electrons encounter this situation, the current in the galvanometer will be significantly reduced. In order to eliminate the influence of space charge on cathode electron emission, another grid is added near the cathode to form a tetrode. Cathode K, screen P, G1, and G2 are the first and second grids respectively. U G1K The main function is to eliminate the influence of space charge on cathode electron emission and improve emission efficiency. G2-P adds reverse voltage to form a repulsive electric field. Electrons are emitted from K, gain energy in the K-G2 interval, and lose energy in the G2-P interval. If the kinetic energy of electrons entering the G2-P region is greater than or equal to eU G2K , it can reach the screen to form a current I. Since the internal energy of the atom is quantized, the current of the screen will fluctuate regularly with the increase of the acceleration voltage. The potential difference between two adjacent peaks or troughs is the excited state potential of the atom.

[0003] The Franck-Hertz experiment is a classic physics experiment that has been incorporated into university physics experimental courses. Many universities in China offer Franck-Hertz experiments in their modern physics experimental courses, primarily using the integrated "Argon Atom Franck-Hertz Experiment" as the primary teaching device. This instrument can demonstrate the excitation phenomenon of the first excited state of argon atoms and measure the excitation potential of the first excited state of argon atoms. Currently, there are many problems with using the integrated "Franck-Hertz Experiment" for physics experimental teaching: the instrument structure is closed, the parameter adjustment range is small, and the experimental content is monotonous. Students can only passively use a set of commercial instruments and cannot actively operate or freely combine experimental equipment, making it impossible to independently explore novel physical phenomena. Summary of the Invention

[0004] The present invention addresses the shortcomings of existing technologies by providing an open-type Franck-Hertz experimental instrument and method. This instrument allows for the free combination of experimental equipment, independent construction of test circuits, and observation of excited states of argon atoms. The instrument also measures the excitation potential of excited states of argon atoms and the characteristic curve of vacuum tubes. The Franck-Hertz experimental instrument provided by the present invention features an open structure, free combination of functional modules, and strong hands-on practicality. It also offers a wide range of parameter adjustments, novel experimental results, rich research content, and a strong sense of free exploration.

[0005] In a first aspect, the present invention provides an open Franck-Hertz experimental instrument. The instrument has an open structure and freely combinable functional modules, capable of measuring both the excited-state potential of argon atoms in an argon-filled electron tube and the characteristic curve of a vacuum electron tube. The functional modules of the instrument include a signal generator, a digital oscilloscope, a DC power supply, and an open Franck-Hertz experimental device. The open Franck-Hertz experimental device is composed of functional modules, including an argon-filled electron tube, a vacuum electron tube, an operational amplifier, a low-pass filter circuit, an instrumentation amplifier, a nanoampere ammeter, a potentiometer, and a battery.

[0006] The excited state potential of the argon atom is observed and measured as follows:

[0007] The functional modules used are: argon-filled electron tube, signal generator, operational amplifier, DC power supply, battery 1, potentiometer, battery 2, instrumentation amplifier, low-pass filter circuit, digital oscilloscope and nanoampere ammeter;

[0008] The connections and operating procedures of the various functional modules are as follows: a DC power supply is connected to the argon-filled electron tube to regulate the tube's filament voltage and grid voltage; battery 1 is connected to a potentiometer connected to the argon-filled electron tube, which controls the tube's rejection voltage; and battery 2 provides power for the instrumentation amplifier. When observing the argon-filled electron tube signal using a digital oscilloscope, a signal generator is connected to an operational amplifier between the tube's cathode and the first grid. The first grid's sweep voltage ranges from 0V to 80V, enabling observation of higher excited states of argon atoms. When the first grid's sweep voltage is greater than 80V, argon atomic ionization can be observed. When measuring the argon-filled electron tube signal using a nanoampere ammeter, the tube's electrical signal passes through a low-pass filter circuit and is then input to the nanoampere ammeter, displaying the tube's current changes and measuring the excited-state potential of the argon atoms.

[0009] The characteristic curve of the vacuum tube is measured as follows: the functional modules used include a vacuum tube, a signal generator, an operational amplifier, a DC power supply, a digital oscilloscope and a nanoampere ammeter;

[0010] The connection and working process of each functional module are as follows: a DC power supply is connected to the vacuum tube to regulate the filament voltage and grid voltage of the vacuum tube; a signal generator is connected to an operational amplifier to generate an electrical signal and input it into the vacuum tube; the electrical signal of the vacuum tube is input into a digital oscilloscope to display the characteristic curve of the vacuum tube or the electrical signal of the vacuum tube is input into a nanoampere ammeter to display the current change of the vacuum tube.

[0011] In a second aspect, the present invention provides an open Franck-Hertz experimental method, which is implemented as follows:

[0012] (1) The observation and measurement of the excited state potential of argon atoms are:

[0013] An argon-filled electron tube is used to observe the excitation curve of the excited state of argon atoms. A DC power supply is connected to the argon-filled electron tube to adjust the filament voltage and the first grid voltage of the argon-filled electron tube respectively; battery 1 is connected to the argon-filled electron tube to adjust its rejection voltage through a potentiometer; battery 2 provides working power for the instrument amplifier; a signal generator generates a sawtooth voltage signal, and the operational amplifier amplifies the voltage signal and inputs it to the second grid of the argon-filled electron tube; the current signal of the argon-filled electron tube is amplified and converted into a voltage signal by the instrument amplifier in turn, and after being processed by a low-pass filter circuit, it is input to a digital oscilloscope, and the scanning voltage of the second grid is between 0V and 80V, and the excitation curve of the first excited state of the argon atom is displayed in real time; or the current signal of the argon-filled electron tube is processed by a low-pass filter circuit and input to a nanoampere ammeter, which displays the current change of the argon-filled electron tube in real time, and can measure the potential of the first excited state of the argon atom;

[0014] A DC power supply is connected to the argon-filled electron tube to regulate the filament voltage and the second grid voltage of the argon-filled electron tube respectively; battery 1 is connected to the argon-filled electron tube to regulate its rejection voltage through a potentiometer; battery 2 provides working power for the instrument amplifier; a signal generator generates a sawtooth voltage signal, and the operational amplifier amplifies and processes the voltage signal before inputting it into the first grid of the argon-filled electron tube; when a digital oscilloscope is used to observe the argon-filled electron tube signal, the current signal of the argon-filled electron tube is amplified and converted into a voltage signal by the instrument amplifier in turn, and then processed by a low-pass filter circuit before being input into the digital oscilloscope, with the scanning voltage of the first grid being between 0V and 80V, and the excitation curve of the higher excited state of the argon atom is displayed in real time. When the scanning voltage of the first grid is greater than 80V, the ionization phenomenon of the argon atom is observed; when a nanoampere ammeter is used to measure the argon-filled electron tube signal, the current signal of the argon-filled electron tube is processed by a low-pass filter circuit before being input into the nanoampere ammeter, and the current change of the argon-filled electron tube is displayed in real time, so that the potential of the higher excited state of the argon atom can be measured;

[0015] (2) The characteristic curve of the vacuum tube is measured as follows:

[0016] Use a vacuum tube and observe its characteristic curve as follows: a DC power supply is connected to the vacuum tube to adjust the filament voltage, grid voltage, and screen voltage of the vacuum tube respectively; a signal generator generates a sawtooth voltage signal; an operational amplifier amplifies the voltage signal and then inputs it into the vacuum tube; the electrical signal of the vacuum tube is input into a digital oscilloscope to display the characteristic curve of the vacuum tube, or the electrical signal of the vacuum tube is input into a nanoampere ammeter to display the current change of the vacuum tube.

[0017] The advantages of the present invention compared with the prior art are:

[0018] (1) The existing Franck-Hertz instrument is a closed structure, and its disadvantage is that it can only observe the first excited state of argon atoms. The Franck-Hertz instrument of the present invention has an open structural design feature, and functional modules can be freely combined. By combining different modules, the first excited state and higher excited states of argon atoms can be observed and measured simultaneously in the open Franck-Hertz instrument. The present invention uses the close distance between the cathode of the argon-filled electron tube and the first grid to obtain a higher electric field strength, thereby realizing the observation of higher excited states and ionization phenomena of argon atoms.

[0019] (2) The existing Franck-Hertz experimental instrument has a small parameter adjustment range, and its disadvantage is that the first grid voltage can only be adjusted between 0-7V, and only the first excited state of argon atoms can be observed. The Franck-Hertz experimental instrument of the present invention has a wide parameter adjustment range. The operational amplifier outputs a sawtooth voltage of 0-80V, providing a first grid scanning voltage for the argon-filled electron tube, which can display the excitation curve of the higher excited state of argon atoms in real time; it outputs a sawtooth voltage greater than 80V, providing a first grid scanning voltage for the argon-filled electron tube, which can realize the observation of the ionization phenomenon of argon atoms. The present invention not only realizes the observation of the first excited state of argon atoms, but also can observe novel higher excited states of argon atoms and even ionization phenomena, and the experimental phenomena are richer.

[0020] (3) The existing Franck-Hertz experimental instrument has a single electron tube, which has the disadvantage of only having an argon-filled electron tube and can only complete the observation of the first excited state of argon atoms. The Franck-Hertz experimental instrument of the present invention has not only an argon-filled electron tube but also a vacuum electron tube. By combining different modules, the argon atom excited state observation experiment of the argon-filled electron tube and the vacuum electron tube characteristic experiment are simultaneously realized, and the experimental scalability is stronger. The characteristic measurement of the vacuum electron tube helps to better understand the measurement of the atomic excited state curve in the Franck-Hertz experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the circuit diagram of the Franck-Hertz experimental apparatus;

[0022] Figure 2 This is a schematic diagram of the functional modules of the open Franck-Hertz experimental device of the present invention, which is used for observing the excited states of argon atoms in an argon-filled electron tube;

[0023] Figure 3 This is a schematic diagram of the functional modules of the open-type Franck-Hertz experimental device of the present invention, which is used to observe the characteristic curve of a vacuum tube;

[0024] Figure 4 This is the first excited state excitation curve of the argon-filled electron tube;

[0025] Figure 5 This is the higher excited state excitation curve of the argon-filled electron tube;

[0026] Figure 6 The corresponding relationship between the scanning voltage and the screen current of the first excited state of the argon-filled electron tube;

[0027] Figure 7 The corresponding relationship between the scanning voltage and the plate current of the higher excited state of the argon-filled electron tube;

[0028] Figure 8 is the corresponding relationship between the plate voltage and the plate current of the vacuum tube;

[0029] Figure 9It is the corresponding relationship between the grid voltage and the screen current of the vacuum tube. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementation methods.

[0031] like Figure 2 As shown in Figure 3, the present invention is an open Franch-Hertz experimental instrument, which consists of a signal generator, a digital oscilloscope, a DC power supply, and an open Franch-Hertz experimental device. The open Franch-Hertz experimental device mainly includes functional modules such as an argon-filled electron tube (i.e., a Franch-Hertz tube), a vacuum electron tube, an operational amplifier, a low-pass filter circuit, an instrumentation amplifier, a nanoampere ammeter, a potentiometer, and a battery. Battery 1 provides a rejection voltage for the Franch-Hertz tube's plate P, and battery 2 provides an operating voltage for the instrumentation amplifier.

[0032] like Figure 2 As shown, an open-type Franck-Hertz instrument is used to observe the excited-state potential of argon atoms, demonstrating the combination and connection of functional modules. A signal generator generates an electrical signal through an operational amplifier and inputs it into an argon-filled electron tube. A DC power supply is connected to the argon-filled electron tube to control the tube's filament and grid voltages. Battery 1 is connected to a potentiometer, which controls the tube's rejection voltage. The tube's electrical signal passes through an instrumentation amplifier and a low-pass filter circuit before being input to a digital oscilloscope, displaying the argon atom excitation curve. Alternatively, a DC power supply is connected to the argon-filled electron tube to control the tube's filament and grid voltages, and battery 1 is connected to a potentiometer, which controls the tube's rejection voltage. The tube's electrical signal passes through a low-pass filter circuit and is then input to a nanoampere ammeter, displaying the tube's current changes.

[0033] like Figure 3 As shown, an open Franck-Hertz experimental instrument is used to observe the characteristic curve of the vacuum tube, and the combination and connection of functional modules. The signal generator is connected to the operational amplifier to generate an electrical signal input into the vacuum tube, and the DC power supply is connected to the vacuum tube to regulate the filament voltage, grid voltage and screen voltage of the vacuum tube. The electrical signal of the vacuum tube is input into a digital oscilloscope to display the characteristic curve of the vacuum tube; or the DC power supply is connected to the vacuum tube to regulate the filament voltage, grid voltage and screen voltage of the vacuum tube. The electrical signal of the vacuum tube is directly input into a nanoampere ammeter to display the current change of the tube. The present invention provides an open Franck-Hertz experimental instrument, which has the following specific applications:

[0034] like Figure 2 As shown, an open Franck-Hertz experimental apparatus is used to perform Experiment 1 to observe the excitation phenomenon of the excited state of argon atoms and the combination and connection of functional modules.

[0035] An argon-filled electron tube is selected, and a DC power supply is connected to the filament of the argon-filled electron tube to emit thermal electrons by heating the filament of the electron tube. The DC power supply is connected between the cathode K and the first grid G1 to provide an acceleration voltage. The signal generator generates a sawtooth wave signal and inputs it into the operational amplifier. The sawtooth wave signal processed by the operational amplification is connected between the first grid G1 and the second grid G2 to provide a scanning voltage. Battery 1 is connected between the screen P and the instrument amplifier to provide a rejection voltage. The screen P is connected to the instrument amplifier, low-pass filter circuit and digital oscilloscope in sequence. Battery 2 is connected to the instrument amplifier to provide the working voltage. The signal output by the screen P is amplified and filtered and then input into the digital oscilloscope, and the excitation curve of the first excited state of the argon atom can be observed. For example, when the filament voltage U F =2.3V, first gate voltage U KG1 =1.5V, rejection voltage U G2P =9V, the second gate scanning voltage U G1G2 Between 0V and 80V, the excitation curve of the first excited state of the argon atom is as follows: Figure 4 shown.

[0036] Select an argon-filled electron tube, connect a DC power supply to the filament of the argon-filled electron tube, and emit thermal electrons by heating the filament of the electron tube. Connect the DC power supply between the first grid G1 and the second grid G2 to provide an acceleration voltage. The signal generator generates a sawtooth wave signal and inputs it into the operational amplifier. The sawtooth wave signal processed by the operational amplification is connected between the cathode K and the first grid G1 to provide a scanning voltage. Battery 1 is connected between the screen P and the instrument amplifier to provide a rejection voltage. The screen P is connected to the instrument amplifier, low-pass filter circuit and digital oscilloscope in sequence. Battery 2 is connected to the instrument amplifier to provide the working voltage. The signal output by the screen P is amplified and filtered and then input into the digital oscilloscope, and the excitation curve of the higher excited state of the argon atom and the ionization phenomenon of the argon atom can be observed. For example, when the filament voltage U F =2.3V, the second gate voltage U G1G2 =20V, rejection voltage U G2P =5.3V, the first gate scanning voltage U KG1 Between 0V and 70V, the excitation curve of the higher excited state of argon atoms is as follows: Figure 5 shown.

[0037] Use the open Franck-Hertz instrument to do experiment 2, measure the excitation potential of the excited state of argon atoms, and combine and connect functional modules, such as Figure 2 shown.

[0038] Select an argon-filled electron tube, connect a DC power supply to the filament of the argon-filled electron tube, and emit thermal electrons by heating the filament of the electron tube. Connect the DC power supply between the cathode K and the first grid G1 to provide an acceleration voltage. Connect the DC power supply between the first grid G1 and the second grid G2 to provide a scanning voltage. Battery 1 is connected between the second grid G2 and the screen P to provide a rejection voltage. A low-pass filter circuit and a nanoampere ammeter are connected between the second grid G2 and the screen P, and the current signal of the screen is filtered and input into the nanoampere ammeter. By measuring the corresponding relationship between the scanning voltage and the screen current, the excitation potential of the first excited state of the argon atom can be obtained. For example, when the filament voltage U F =2.3V, first gate voltage U KG1 =1.5V, rejection voltage U G2P =9V, the second gate scanning voltage U G1G2 Between 10V and 95V, the excitation curve of the first excited state of the argon atom is as follows: Figure 6 shown.

[0039] Select an argon-filled electron tube, connect a DC power supply to the filament of the argon-filled electron tube, and emit thermal electrons by heating the filament of the electron tube. Connect the DC power supply between the cathode K and the second grid G1 to provide a scanning voltage. Connect the DC power supply between the first grid G1 and the second grid G2 to provide an acceleration voltage. Battery 1 is connected between the second grid G2 and the screen P to provide a rejection voltage. A low-pass filter circuit and a nanoampere ammeter are connected between the second grid G2 and the screen P, and the current signal of the screen is filtered and input into the nanoampere ammeter. By measuring the corresponding relationship between the scanning voltage and the screen current, the excitation potential of the higher excited state of the argon atom can be obtained. For example, when the filament voltage U F =2.3V, the second gate voltage U G1G2 =20V, rejection voltage U G2P =5.3V, the first gate scanning voltage U KG1 Between 0V and 61V, the excitation curve of the higher excited state of argon atoms is as follows: Figure 7 shown.

[0040] like Figure 3 As shown, an open Franck-Hertz experimental instrument is used to perform Experiment 3 to measure the characteristic curve of the vacuum tube and the combination and connection of functional modules.

[0041] Select a vacuum tube, connect the DC power supply to the filament of the vacuum tube, and emit thermal electrons by heating the filament of the tube. Connect the DC power supply between the cathode K and the first grid G1 to provide grid voltage. Connect the DC power supply between the cathode K and the screen P to provide screen voltage. The second grid G2 is connected to the screen P, and a nanoampere ammeter is connected between the first grid G1 and the screen P. Fix the grid voltage of the tube, measure the corresponding relationship between the screen voltage and the screen current, and the screen characteristic curve of the tube can be obtained. For example, when the filament voltage UF =6.3V, gate voltage U G =2V, screen scanning voltage U P Between 0V and 120V, the plate characteristic curve of the vacuum tube is as follows: Figure 8 shown.

[0042] A DC power supply is connected to the filament of a vacuum tube, which heats the filament to emit thermal electrons. The DC power supply is connected between the cathode K and the first grid G1 to provide a grid voltage. The DC power supply is connected between the cathode K and the screen P to provide a screen voltage. The second grid G2 is connected to the screen P, and a nanoampere ammeter is connected between the first grid G1 and the screen P. By fixing the screen voltage of the tube and measuring the corresponding relationship between the grid voltage and the screen current, the screen-grid characteristic curve of the tube can be obtained. For example, when the filament voltage U F =6.3V, screen voltage U P =120V, gate scanning voltage U G Between -3V and -1V, the screen grid characteristic curve of the vacuum tube is as follows: Figure 9 shown.

[0043] The above embodiments are provided for the purpose of describing the present invention only and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims. Various equivalent substitutions and modifications made without departing from the spirit and principles of the present invention are intended to be within the scope of the present invention.

Claims

1. An open Franck-Hertz test apparatus, characterized in that: The experimental instrument has an open structure and can freely combine functional modules. It can not only observe and measure the excited state potential of argon atoms in an argon-filled electron tube, but also observe and measure the characteristic curve of a vacuum electron tube. The parameter adjustment range is wide. The operational amplifier outputs a sawtooth voltage of 0-80V to provide a first grid scanning voltage for the argon-filled electron tube, which can display the excitation curve of the higher excited state of the argon atoms in real time. The operational amplifier outputs a sawtooth voltage greater than 80V to provide a first grid scanning voltage for the argon-filled electron tube, which can realize the observation of the ionization phenomenon of argon atoms. The functional modules of the experimental instrument include: a signal generator, a digital oscilloscope, a DC power supply and an open Franck-Hertz experimental device; the open Franck-Hertz experimental device is composed of functional modules, including an argon-filled electron tube, a vacuum electron tube, an operational amplifier, a low-pass filter circuit, an instrumentation amplifier, a nanoampere ammeter, a potentiometer and a battery; The excited state potential of the argon atom is observed and measured as follows: The functional modules used are: argon-filled electron tube, signal generator, operational amplifier, DC power supply, battery 1, potentiometer, battery 2, instrumentation amplifier, low-pass filter circuit, digital oscilloscope and nanoampere ammeter; The connection and working process of each functional module are as follows: a DC power supply is connected to the argon-filled electron tube to regulate the filament voltage of the argon-filled electron tube and the second grid voltage between the first and second grids; battery 1 is connected to the potentiometer and connected to the argon-filled electron tube, and the rejection voltage of the argon-filled electron tube is regulated by the potentiometer, and battery 2 provides working power for the instrument amplifier; when using a digital oscilloscope to observe the argon-filled electron tube signal, a signal generator is connected to the operational amplifier, connected between the cathode of the argon-filled electron tube and the first grid, and provides a scanning voltage. The scanning voltage of the first grid is between 0V and 80V, which can achieve observation of higher excited states of argon atoms; when the scanning voltage of the first grid is greater than 80V, the ionization phenomenon of argon atoms can be observed; when using a nanoampere ammeter to measure the argon-filled electron tube signal, the electrical signal of the argon-filled electron tube passes through a low-pass filter circuit and is input into the nanoampere ammeter to display the current change of the argon-filled electron tube, which can measure the excited state potential of the argon atoms; The characteristic curve of the vacuum tube is measured as follows: the functional modules used include a vacuum tube, a signal generator, an operational amplifier, a DC power supply, a digital oscilloscope and a nanoampere ammeter; The connection and working process of each functional module are as follows: a DC power supply is connected to the vacuum tube to regulate the filament voltage, the first grid voltage between the cathode and the first grid, and the screen voltage of the vacuum tube; a signal generator is connected to the operational amplifier to generate an electrical signal and input it into the vacuum tube; the electrical signal of the vacuum tube is input into a digital oscilloscope to display the characteristic curve of the vacuum tube, or the electrical signal of the vacuum tube is input into a nanoampere ammeter to display the current change of the vacuum tube; 2. An open Franck-Hertz experimental method, characterized in that The implementation is as follows: (1) The excited state potential of argon atoms is observed and measured as follows: An argon-filled electron tube is used to observe the excitation curve of the excited state of argon atoms. A DC power supply is connected to the argon-filled electron tube to regulate the filament voltage and the first grid voltage between the cathode and the first grid of the argon-filled electron tube respectively; battery 1 is connected to the argon-filled electron tube to regulate its rejection voltage through a potentiometer; battery 2 provides working power for the instrument amplifier; a signal generator generates a sawtooth voltage signal, and the operational amplifier amplifies and processes the voltage signal and then inputs it between the first grid and the second grid of the argon-filled electron tube to provide a scanning voltage; the current signal of the argon-filled electron tube is amplified and converted into a voltage signal by the instrument amplifier in turn, and after being processed by a low-pass filter circuit, it is input into a digital oscilloscope, and the scanning voltage of the second grid is between 0V and 80V, and the excitation curve of the first excited state of the argon atom is displayed in real time; or the current signal of the argon-filled electron tube is processed by a low-pass filter circuit and input into a nanoampere ammeter, and the current change of the argon-filled electron tube is displayed in real time, which can measure the excited state potential of the argon atom; A DC power supply is connected to the argon-filled electron tube to regulate the filament voltage of the argon-filled electron tube and the second grid voltage between the first and second grids; a battery 1 is connected to the argon-filled electron tube to regulate its rejection voltage through a potentiometer; Battery 2 provides operating power for the instrumentation amplifier; a signal generator generates a sawtooth voltage signal, and an operational amplifier amplifies and processes the voltage signal before inputting it between the cathode and the first grid of the argon-filled electron tube and providing a scanning voltage; when a digital oscilloscope is used to observe the argon-filled electron tube signal, the current signal of the argon-filled electron tube is sequentially amplified by the instrumentation amplifier and converted into a voltage signal, processed by a low-pass filter circuit, and then input into the digital oscilloscope. The scanning voltage of the first grid is between 0V and 80V, and the excitation curve of the higher excited state of the argon atom is displayed in real time. When the scanning voltage of the first grid is greater than 80V, the ionization phenomenon of the argon atom is observed; when a nanoampere ammeter is used to measure the argon-filled electron tube signal, the current signal of the argon-filled electron tube is processed by a low-pass filter circuit and then input into the nanoampere ammeter, which displays the current change of the argon-filled electron tube in real time, and can measure the excited state potential of the argon atom; (2) The characteristic curve of the vacuum tube is measured as: Using a vacuum tube, the characteristic curve of the vacuum tube is observed as follows: a DC power supply is connected to the vacuum tube to regulate the filament voltage, the first grid voltage between the cathode and the first grid, and the screen voltage of the vacuum tube respectively; a signal generator generates a sawtooth voltage signal, and an operational amplifier amplifies the voltage signal and inputs it into the vacuum tube; the electrical signal of the vacuum tube is input into a digital oscilloscope to display the characteristic curve of the vacuum tube, or the electrical signal of the vacuum tube is input into a nanoampere ammeter to display the current change of the vacuum tube.

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