Professor Wang Limin's steps were a little hurried. After all, he came late today.
As a professor, he has a lot of work, and imparting knowledge is only one aspect of it. He also has his own scientific research work to do. Today, on the weekend, was the time agreed with the students to answer the exercises. However, because he is engaged in scientific research,
Things were delayed. When I looked at my watch, I found that the time had already passed, so I hurried over.
Who would have thought that before entering the classroom door, I heard Bai Jiuming's words, and suddenly felt a little stunned.
People from outside? Say they made a mistake?
A monk on the way?
Regarding the latter sentence, he actually somewhat agreed with it. Yes, he became a monk halfway.
Electronics has not been established for a long time. All breakthroughs were made in this century. It is not as historical as other technologies. At the same time, this also means that it is a subject that is constantly innovating and developing.
When Wang Limin was in school, there were only analog circuits, and it was still the era when electron tubes were mainly used. It was not until he went to the Soviet Union to study that he began to come into contact with the knowledge of transistors. Various circuits were built using these components.
Electronic signals are transmitted internally according to specific waveforms and change continuously. This is an analog circuit.
The entire country, in terms of electronics, is almost entirely based on analog circuits.
However, the times are constantly developing and progressing. Digital circuits have developed rapidly in these years, and the country is starting from scratch. A few years ago, Wang Limin purchased several books on digital circuits at his own expense and began to study on his own.
It can be regarded as self-taught.
As a result, last year, the first-year official college entrance examination was held to select talents. At the same time, various colleges and universities officially resumed teaching, and the Industrial College made some improvements and added some courses.
This digital circuit is an additional course. After all, it follows the trend of the world. Universities cultivate talents and must be in line with the world. In this regard, they cannot fall behind.
However, after it was opened, it was discovered that there were no teachers at all! The only talents in the country who were proficient in digital circuit technology were hired by other universities, especially institutions like Tsinghua University, where the Industrial College could not compete at all.
,So, after all the freshmen were enrolled, Professor Wang Limin took over the task of teaching digital circuits.
Therefore, it was also his first year of teaching, and he encountered some problems, which he expected. Now, when he heard Bai Jiuming say that someone questioned his teaching, there was no trace of dissatisfaction on his face after his authority was questioned.
After the initial shock, a smile appeared on his face: "Oh? Really? Who is it?"
While he was talking, he had already walked to the door of the classroom, and then he saw under the podium, it was his favorite student Wang Xiaoyu. This child had the highest score in the exam, but that was only because he had a lot of bonus points in foreign languages. The real
She didn’t even have solid science knowledge, and she had chosen her current major, which was not suitable for a girl like her. However, Wang Xiaoyu was not discouraged and had been studying seriously, which made Professor Wang Limin very satisfied.
Next to her, there were several people, two men and one woman. One of the boys had a special temperament, which immediately attracted his attention.
"It's him, it's him." Bai Jiuming was filled with joy at this time. Professor Wang came just in time. I want to test you, but if you don't accept the offer, let Professor Wang test you! Huh, let's see how you step down now.
!
If it were someone else, Bai Jiuming might have saved face for him, but now it was Qin Zhenhua, a love rival who could only talk and talk. Of course he wanted to push Qin Zhenhua to death.
"Professor Wang, look at the blackboard. He is saying that the circuit diagram you drew was superfluous and erased part of the circuit." Bai Jiuming continued.
He wasn't lying, that's what Qin Zhenhua said, so he was very proud. Let's see how Qin Zhenhua denies it now.
At this time, Wang Xiaoyu felt a little panicked. She bit her lip with her teeth and wanted to explain something. However, she felt it was difficult to say something because she was afraid that if she said the wrong thing and hurt Qin Zhenhua's heart, he would not come to him again.
"Oh?" When he saw this circuit diagram, Wang Limin's eyes suddenly lit up.
In this era, university education is actually not particularly standardized. There are no various teaching materials reviewed and issued by higher-level authorities, especially for this newly opened discipline. It can be said that everything is just crossing the river by feeling for the stones. The handouts are those provided by Wang Limin.
During the holidays, he carved the stencil paper himself, then printed it, and used it directly as a teaching material. Of course, he collected and organized this from the materials he purchased at his own expense, and it took a lot of effort.
As for this circuit diagram, Wang Limin remembers it very clearly. In his information, it is as it is now. He has erased other parts, leaving a rather concise part.
However, he always felt that this was a blind eye, and he could only see part of it, and had no idea how it worked. Therefore, in order to deepen his understanding, he used the accumulated knowledge of the original analog circuit to complete the supplement. During the lecture,
At that time, I also focused on talking about it, and I felt very complacent at that time.
But now, he was brushed off by the other party and said that he was superfluous. He was not angry, but was filled with excitement and thirst for knowledge.
"Young man, tell me why those things are not important?" Wang Limin said to Qin Zhenhua.
Bai Jiuming was standing aside, feeling very happy, "Okay, look, our Professor Wang is here to give you a test, let's see what else you can say!"
Wang Xiaoyu pinched the corner of her clothes nervously. How would Brother Zhenhua explain this? Don't let your friendship get hurt.
After all, on one side is Brother Zhenhua, whom I think about day and night, and on the other side is the highly respected professor.
"Professor Wang, what class is this?" No one expected that Qin Zhenhua actually started to ask Professor Wang back!
"Digital circuits." Wang Limin was asked a question, and he answered directly without too much dissatisfaction: "Digital circuits are called digital circuits for short. In the past, analog circuits were called analog circuits for short."
"Yes, Professor Wang, this is a digital circuit!" Qin Zhenhua pointed at the blackboard and said: "In a digital circuit, all variables are boiled down to two opposing states of 0 and 1. This can be expressed by the presence or absence of a signal.
The level is high or low, the switch is on or off, etc. We only care about its state and do not care about the detailed value of a variable. For example, small changes in the level amplitude may be meaningless."
"But what about you? You have spent a long time here just to tell everyone how the current flows? We don't need to know this. We only know whether the one that goes in is 0 or 1, and the one that comes out is 0 or 1. That's enough
If other doping comes in, it will be superfluous, meaningless, and will cause extreme confusion." Qin Zhenhua shook his head helplessly: "Digital electricity is digital electricity, analog electricity is analog electricity, even if you talk about AD and DA
Conversion (analog-to-digital conversion) cannot be mixed up!”
When he said this, there was already a tone of hatred in his words. This teaching is a complete mess and is misleading the disciples.