Otaku Engineer in Great Tang Dynasty Chapter 1425: Electronic 2-pole tube!

"There is another way to convert alternating current into direct current!"

In the workshop, Mo Lingwei's laboratory, Li Zexuan put down the pen and paper in his hand and spoke.

Mo Lingwei and Wang Ji couldn't help being surprised when they heard that, Mo Lingwei said: "Shanchang, how can this alternating current be converted into direct current?"

Li Zexuan smiled and said: "Whether it is AC or DC, they are all electricity, and of course they can be converted into each other! With a rectifier circuit, AC power can be converted into DC power, and with an inverter circuit, DC power can be converted into Alternating current! However, a new electronic component rectifier diode is needed in the rectifier circuit. This diode has unidirectional conductivity and can only pass current in one direction. With it, we can build a rectifier circuit!"

Mo Lingwei immediately became interested when she heard this. She quickly asked: "Shan Chang, what should I do with this rectifier diode? Can you teach me?"

The knowledgeable first female professor of Yanhuang Academy in the eyes of others, at this moment, like an ignorant student, is absorbing knowledge frantically from Li Zexuan.

Li Zexuan pondered for a moment, and said: "This rectifier diode can be divided into electronic diodes and crystal diodes according to different materials. According to our current conditions, we can try to make some electronic diodes! Miss Mo, Mr. Wang, I Today I will teach you how to make this electronic diode. You have to promise me never to leak it, otherwise not only the workshop will suffer losses, but Datang will also suffer losses!"

Finally, Li Zexuan solemnly charged Mo Lingwei and Wang Ji.

Electronic diodes, also called vacuum diodes, are widely used in voltage stabilizing and rectifying circuits because of their unidirectional conductivity. Throughout the entire history of human integrated circuit development, the invention of electronic diodes can be regarded as the starting point of the human electronics industry, so Li Zexuan cannot be taken seriously.

In the previous life, after the invention of the electronic diode, American inventor De Forest cleverly added a grid plate between the diode filament and the plate, making the world's first electronic triode. Since then, the electronic components sealed in "small glass bottles" have been widely used in various electronic product fields. Electronic products such as TVs, radios, and loudspeakers are all inseparable from diodes and transistors!

However, the shortcomings of electronic diodes and electronic triodes are also obvious: high power consumption, large heat generation, large volume, and short life span, so people are always looking for new electronic devices to replace them. It was not until the birth of the transistor and the arrival of the era of solid-state electronic technology that electron tubes were completely replaced!

In the 21st century, the diodes and triodes used in countries all over the world are actually transistors. Of course, there is also another name called semiconductor tube, because they are made of semiconductor material silicon or germanium. With Datang’s current industrial foundation, firstly, purification of silicon or germanium is a problem, and secondly, the production of the key structure pn junction in semiconductor diodes is also a considerable problem.

The so-called pn junction is the use of different doping processes, through diffusion, p-type semiconductor and n-type semiconductor are fabricated on the same semiconductor substrate, and a space charge area is formed at their junction, which is called pn junction. The pn junction has unidirectional conductivity. Among them, n-type semiconductor is silicon crystal (or germanium crystal) doped with a small amount of impurity phosphorus element, and p-type semiconductor is silicon crystal (or germanium crystal) doped with a small amount of impurity boron element.

Li Zexuan does not have boron on hand now, so he temporarily gave up this plan of manufacturing crystal diodes!

"Don't worry about the mountain leader, Wang will never say a word to outsiders what the mountain leader said here today, even if he is drunk!"

Wang Ji was the first to bow his hand, but the second half of the sentence was a bit dumbfounding.

It is reassuring to say that although this old guy is a drunkard, he doesn't talk nonsense when he is drunk.

"Shanchang, I won't leak what you said, I...I use my life guarantee!"

Listening to Li Zexuan and Wang Ji both being very solemn, Mo Lingwei also became serious and said to Li Zexuan.

Li Zexuan nodded and said: "That's good! Next I will tell you how to make this electronic diode!"

Speaking, Li Zexuan picked up paper and pen again, and while drawing a sketch, he explained: "First, we sealed two metal pieces in the vacuum glass tube. Of course, we can also use the method we used to make electric lights. The oxygen in the tube is exhausted, and a complete vacuum is not required. After that, after we add alternating current to the anode plate, a constant current with the same direction will appear on the other plate!"

Mo Lingwei was a little puzzled: "Shanchang, what is the principle?"

Li Zexuan thought for a while and explained: "Look, when the anode potential is higher than the cathode, the electrons emitted by the cathode move towards the anode to form an electron flow under the action of the electric field. When the cathode voltage is higher than the anode, the electrons The received electric field force pulls the electrons back to the cathode and cannot generate current, so this electronic diode has unidirectional conductivity and can be used for circuit rectification!"

In fact, this effect was called the "Edison Effect" in the previous life.

In 1883, in order to find the best filament material for electric bulbs, Edison placed a section of copper wire near the carbon filament inside the vacuum bulb in order to prevent the carbon filament from evaporating. Although he failed, he accidentally discovered that the copper wire that was not connected to the circuit produced a weak current due to the hot electrons emitted by the carbon wire. Although Edison did not study this phenomenon carefully, he applied for the patent "Edison Effect~IndoMTL.com~" for this purpose. When Fleming was researching and improving the detector in the radiotelegraph receiver, he envisaged using the Edison effect for detection. He encapsulated two metal sheets in a vacuum glass tube and applied a high-frequency alternating voltage to the anode plate. The Edison effect appeared, and the alternating current was transformed into a direct current when the alternating current passed through the device. Fleming installed this with two The tube with one electrode is called a vacuum diode, which has two functions of rectification and detection. This is the first electronic device in human history.

What Li Zexuan has 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.

"Shanchang, I understand! Generally speaking, the structure of this electronic diode is not complicated. Although it takes a lot of work, it is not impossible to make it. Let me try something. Times!"

Mo Lingwei thought about it for a long time after listening to Li Zexuan's explanation, and finally nodded.

Wang Ji also said: "Wang probably understands it too! I will definitely assist Miss Mo to make the electronic diode!"

Mo Lingwei's progress here is directly related to whether his electrolysis workshop can proceed normally, of course he is more concerned than anyone else!

Li Zexuan nodded and said: "That's hard work! But in my opinion, DC generators and electronic diodes can be manufactured at the same time! Whichever is made first, put into use first, and the electrolysis workshop can start earlier!"

To be on the safe side, Li Zexuan decided to have both hands hard and both hands should be grasped!

"Yes! The mountain is long!"

The two clung to each other.

Li Zexuan nodded in satisfaction, and said in his heart: With diodes, the triode is not far away, and many electrical appliances can be made by then, and Datang will soon enter the electronic age!

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