"There is another way to convert alternating current into direct current!"
In the workshop and Mo Lingwei's laboratory, Li Zexuan put down the pen and paper in his hand and spoke.
When Mo Lingwei and Wang Ji heard this, they couldn't help but feel shocked. Mo Lingwei said: "Chief Mountain, how can this alternating current be converted into direct current?"
Li Zexuan smiled and said: "Whether it is alternating current or direct current, they are both electricity, and of course they can be converted into each other! Using a rectifier circuit, you can convert alternating current into direct current, and using an inverter circuit, you can convert direct current into alternating current! However, , a new electronic component is needed in the rectifier circuit - the rectifier diode. This diode has one-way conductivity and can only pass current in one direction. With it, we can build a rectifier circuit!"
When Mo Lingwei heard this, she immediately became interested. She quickly asked: "Chief, what should I do with this rectifier diode? Can you teach me?"
The most knowledgeable female professor of Yanhuang Academy in the eyes of others is now like an ignorant student, crazily absorbing knowledge from Li Zexuan.
Li Zexuan pondered for a moment and said: "These rectifier diodes can be divided into electronic diodes and crystal diodes according to different materials. According to our current conditions, we can try to make electronic diodes! Miss Mo, Mr. Wang, I will make this today I will teach you how to make electronic diodes, but you must promise not to let it out, otherwise not only will the workshop suffer losses, but Datang will also suffer losses!"
Finally, Li Zexuan solemnly gave instructions to Mo Lingwei and Wang Ji.
Electronic diodes, also called vacuum diodes, are widely used in voltage stabilization and rectification circuits because of their unidirectional conductivity. Throughout the entire history of human integrated circuit development, the invention of the electronic diode can be regarded as the starting point of the human electronics industry, so Li Zexuan cannot help but take it seriously.
In a previous life, after the invention of the electronic diode, the American inventor De Forest cleverly added a grid between the diode filament and the plate, creating the world's first electronic triode. Since then, this kind of electronic components sealed in "small glass bottles" have been widely used in various electronic products. Electronic products such as televisions, radios, amplifiers, etc. are all inseparable from diodes and triodes!
However, the shortcomings of electronic diodes and electronic transistors are also obvious - high power consumption, high heat generation, large size, and short lifespan, so people have been looking for new electronic devices to replace them. It was not until the birth of the transistor and the advent of the era of solid electronic technology that the electron tube was completely replaced!
In the 21st century, diodes and transistors used in various countries around the world are actually transistors. Of course, they are also called semiconductor tubes, because they are made of semiconductor materials silicon or germanium. Based on Datang's current industrial base, first of all, purifying silicon or germanium is a problem. Secondly, the production of the PN junction, a key structure in semiconductor diodes, is also a considerable problem.
The so-called PN junction uses different doping processes to make P-type semiconductors and N-type semiconductors on the same semiconductor substrate through diffusion. A space charge region is formed at their junction, which is called a PN junction. The PN junction has One-way conductivity. Among them, N-type semiconductor is a silicon crystal (or germanium crystal) doped with a small amount of impurity phosphorus element, and P-type semiconductor is a silicon crystal (or germanium crystal) doped with a small amount of impurity boron element.
Li Zexuan doesn't have boron on hand yet, so he has temporarily given up on the plan to make crystal diodes!
"Don't worry, Chief. Wang will never say a word of what Chief said here to outsiders today, even if he is drunk!"
Wang Ji was the first to say, but the second half of his sentence made people dumbfounded.
It is said that although this old guy is an alcoholic, he does not talk nonsense when he is drunk, which is quite reassuring.
"Chief, I won't leak what you said. I...I will guarantee it with my life!"
After hearing what Li Zexuan and Wang Ji said very seriously, Mo Lingwei also became serious and said to Li Zexuan.
Li Zexuan nodded and said: "Okay! Next, I will tell you how to make this electronic diode!"
As he said that, Li Zexuan picked up the pen and paper again, and while drawing a sketch, he explained: "First, we seal two metal pieces in the vacuum glass tube. Of course, we can also use the method we used to make electric lamps to seal the metal pieces in the glass tube. It is enough to use up the oxygen, there is no need for a complete vacuum. After that, after we apply alternating current to the anode plate, a constant current with no change in direction will appear on the other plate!"
Mo Lingwei was a little puzzled and said: "Chief Mountain, what is the principle of this?"
Li Zexuan thought for a while and explained: "You see, when the anode potential is higher than the cathode, the electrons emitted by the cathode move toward the anode under the action of the electric field to form an electron flow. When the cathode voltage is higher than the anode, the electric field experienced by the electrons The force pulls electrons back to the cathode and cannot generate current, so this electronic diode has one-way conductivity and can be used for circuit rectification!"
In fact, this effect was called the "Edison effect" in previous lives.
In 1883, in order to find the best filament material for electric light bulbs, Edison placed a piece of copper wire near the carbon filament inside the vacuum bulb, hoping to prevent the carbon filament from evaporating. Although it failed, he accidentally discovered that the copper wire not connected in the circuit generated a weak current because it received the hot electrons emitted by the carbon wire. Although Edison did not study this phenomenon carefully, he applied for a patent for the "Edison Effect".
In 1896, when Fleming was studying to improve the detector in the wireless telegraph receiver, he envisioned using the Edison effect for detection. He encapsulated two metal sheets in a vacuum glass tube and applied high-frequency alternating voltage to the anode plate. The Edison effect occurred. When the alternating current passed through this device, it was turned into direct current. Fleming called this tube equipped with two electrodes a vacuum diode. It had both rectifying and detecting functions. It was the first electronic device in human history.
What Li Zexuan wants to do now is this kind of vacuum diode! Although he knew the principle, he was really not sure whether it could be done in the end.
"Shan Zhang, I generally understand! Generally speaking, the structure of this electronic diode is not complicated. Although it takes a lot of work to make, it is not impossible to make it. Please let me try it a few times!"
After listening to Li Zexuan's explanation, Mo Lingwei thought alone for a long time and finally nodded.
Wang Ji also held up his hands and said: "Wang probably understands! I will definitely help Miss Mo to make electronic diodes!"
Mo Lingwei's progress is directly related to whether his electrolysis workshop can continue normally. Of course, he cares about it more than anyone else!
Li Zexuan nodded and said: "That's a lot of hard work for both of you! But in my opinion, DC generators and electronic diodes can be manufactured simultaneously! Whichever one is built first will be put into use first, and the electrolysis workshop can also start earlier!"
To be on the safe side, Li Zexuan decided to be tough with both hands and grasp with both hands!
"Yes! Chief Shan!"
The two of them cupped their hands in response.
Li Zexuan nodded with satisfaction and thought to himself: With the diode, the triode is not far away. By then, many electrical appliances will be built, and Datang will soon enter the electronic age!
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