The ups and downs of life in the Siheyuan

Li Yuan taught while grinding.

This knowledge comes from "Primary Materials Chemistry".

His abnormal insight and muscle control ability once again helped him turn knowledge into his own skills.

After grinding dozens of times, he has completely mastered the grinding skills.

He changed to a finer grinding disc and began the final polishing.

After finishing the polishing, the next step is to install the conductive electrode.

Due to limited conditions, Li Yuan chose the silver layer penetration method.

He handed two polished ceramic pieces to Xiao Jian.

Xiao Jian put on rubber gloves and began to penetrate the electrodes.

He has done these tasks more than a dozen times, and he is already familiar with such a simple process.

While Xiao Jian was processing the electrodes, Li Yuan guided Wang Jingxiang to start grinding other ceramic pieces.

It's a pity that she didn't control her strength well. The first piece was thrown away and shattered after hitting the wall.

Although she was a little nervous and embarrassed, she didn't apologize profusely like before.

As long as it was not intentional or unfocused, Li Yuan would not blame them, but would encourage them to continue.

This makes them very lucky. Many senior brothers and sisters will be severely criticized if they make mistakes when doing the project.

This has nothing to do with character, but with the current scarcity of materials. Teachers do not have many resources to allocate. Once mistakes are made and wasted, they will be heartbroken for a long time.

"Relax, don't be nervous, these things are nothing to me."

Wang Jingxiang blushed and nodded.

She picked up another piece and started grinding it.

"Pay attention, relax a little..."

"Press a little harder on your ring finger...Okay, keep it..."

Li Yuan senses her control over the ceramics through telepathy.

Ten minutes later, seeing her entering the state, Li Yuan came to Xiao Jian again.

"Not bad, polished very well."

Xiao Jian raised his head and smiled, then lowered his head and looked at the ceramic piece intently.

Before school, in addition to scrapping two pieces, we got 6 ceramic pieces with complete craftsmanship.

Xiao Jian also scrapped a piece during the infiltration, which is fair.

After cleaning, put it on a wooden rack to dry in the shade. I will test it tomorrow.

The next day, the piezoelectric ceramics that Li Yuan had been thinking about were finally declared successful.

Each piece is about the size of an adult fingernail, and different pressure deformations will produce different voltages.

"Xiao Jian and Wang Jingxiang, you two, draw the curves of the parameters of all six pieces of piezoelectric ceramics.

At the same time, we will further improve the process flow of grinding and silver layer infiltration method."

The two of them nodded in agreement.

Next, Li Yuan used electron tubes as the main component and designed a second-order amplification circuit based on the amplification circuit principle of the 911 computer.

Unfortunately, no useful information has been captured.

The cumulative effect of charge on the piezoelectric ceramic can be seen with a mechanical voltmeter.

But after two levels of amplification, no voltage fluctuations could be seen, even though Li Yuan had almost folded the ceramic piece.

Two days later, Li Yuan had to give up trying and found Director Li.

After listening to Li Yuan's description, Director Li took Li Yuan to the Department of Radio Engineering and found an old professor.

"Professor Xu, I have something to trouble you with. Do you think you have time now?"

Director Li, who is in his 40s, was also respectful when he saw Professor Xu.

"Xiao Li, tell me, what's going on?"

"Let me introduce you, this is classmate Li Yuan, he has participated in..."

"Haha, no introduction is needed. A legendary kid who doesn't love art but loves science has participated in the development of parallel 4-cylinder diesel engines and the development of 911 computers.

Halfway through, the brushless DC motor was invented, bringing the motor into the silent era.

I have heard about your deeds for a long time.

It's a pity that brushless motors have entered the ranks of confidentiality, otherwise, your kid will be famous all over the world in no time.

how? If you have any questions that you can't figure out, come to my old man."

Professor Xu even knows about brushless motors, so it seems that his status is not low.

"Haha, Mr. Xu, you are so amazing," Director Li exaggerated.

"You're too old to win. I'm just studying and don't dare to mention participation," Li Yuan said modestly.

"Do you know why I know you so well? Zhang Ran and Tang Kai are both my students and we often interact with each other." At this point, the old man felt a little depressed.

When Tang Kai was mentioned, Li Yuan immediately understood that this person was technician Tang from the radio factory.

“They think very highly of you and you have unique insights in many aspects.

Tang Kai described your actions as "inspiring and inspiring".

Li Yuan looked at Li Yuan in shock. He knew Professor Xu's character, and such a high evaluation must be well-deserved.

"It's all the elders' love that makes you laugh."

"Okay! Okay! Okay! Tell me, if there is anything you need, I will satisfy you, the young Huaqing dragon."

The first time he met Professor Xu, Li Yuan was a little embarrassed by what he said.

Seeing Director Li's expression, he felt a little proud inside.

Li Yuan briefly explained the problems he encountered.

"Hahaha, it's not an exaggeration to say that you are a Huaqing young dragon. I didn't expect that you actually built a dynamic balancer.

Interesting, interesting.

Well, how about you come to my radio and listen in? "

The old man's words seemed like a joke, but they actually contained expectations.

"As long as you keep giving me the green light, I'll get whatever I want. However, that's not possible recently. I guess I'll have to wait until my junior year, when I've completed all courses in the Department of Motivation and Computer Science."

"Okay, no problem. Come to me when the time comes and I'll give you the green light," Mr. Xu said firmly.

"Thank you first, um..."

"Don't worry, kid." After saying that, he stood up and walked to the bookcase against the wall and started rummaging through it.

Soon, he came over with two books.

"Take these two books back and read them. If you don't understand, you can come to me at any time. After reading them, you will be able to find the answer."

Li Yuan took it respectfully, and Director Li next to him looked envious.

Looking down, I saw the titles of the books were "Circuit Amplifier" and "Receiving Equipment".

"Xiao Li, the explanations in these two books are relatively basic and thorough, and they can lay the foundation."

"Thank you, Mr. Xu."

On the way, Director Li seemed to meet Li Yuan for the first time.

Professor Xu's evaluation of Li Yuan was so high that he couldn't believe it.

Although Professor Xu is a professor in the Department of Radio Engineering, he actually has another identity, an expert professor in theoretical physics.

He has made outstanding contributions in the field of radio equipment and participated in the derivation of physical formulas for key projects.

Such a person is a veteran of Huaqing University.

He admired Li Yuan so much that Director Li had to think more.

Back in the laboratory, Li Yuan started reading.

After reading through the two books, I have a vague idea in my mind.

Regarding the characteristics of the receiving and amplifying circuits, he knew where problems had arisen in previous designs.

The biggest problem should be the power supply.

Another is that only amplification is considered, and filtering is not considered, resulting in simultaneous amplification of signal noise and the signal being submerged.

Computer circuits are mainly switching quantities and are not sensitive to noise.

According to the book, his acquisition amplification circuit is an analog circuit and has much higher power requirements.

There are also higher requirements for filtering.

After thinking about this, Li Yuan began to modify the circuit.

The biggest change is the power supply, which uses a transformer for voltage division and isolation, and a parallel diode and capacitor filter.

Get the cleanest analog power possible.

Then add an RC filter circuit to the entrance and middle part of the amplifier circuit.

After simple testing, the circuit meets the design expectations.