Huayu for engineering students

Chapter 145
The brothers got the blueprint and the task assigned by Wang Xu.

Part of it is to make this drawing, which is not complicated. Even if the circuit diagram is etched by yourself, these brothers can not be troubled. It is estimated that it can be completed in one day. Wang Xu has ready-made parts here, and it is nothing more than installation and welding.

Welding is a technical job, and a few brothers may not be able to do it, but the department can always find capable ones, so this is not a problem.

Finally, there are various tests and debugging. This is not a problem for the brothers. Borrowing the laboratory is not just a matter of spending money. They don't know that Professor Yan has already prepared the laboratory for them.

The second task is more troublesome. The overall design power of this circuit diagram is low, and it can only be applied to smaller speakers, and it cannot push the big ones with high impedance.

Wang Xu asked them to design two power amplification solutions based on this, one using transistors and the other using electron tubes.

Don't look at just increasing the power, it's not as easy as replacing a few parts, if you can't clearly understand the idea of ​​the whole circuit, what you replace at will may lead to distortion of the circuit effect.

In other words, the originally designed high-fidelity output may become a modulated output that highlights a certain part and weakens another part.

In layman's terms, it is completely different.

And this is the problem that Wang Xu gave them, whether Wang Xu can do it, of course he can, but Wang Xu can't do everything by himself.Leaving them with a topic not only exercises their ability, consolidates their studies, but also reduces their own labor, killing three birds with one stone, so why not do it.

I believe that Teacher Yan also realized Wang Xu's good intentions, so he promised all kinds of convenience so happily, and even the teacher who guided and supervised their studies was ready.

While Wang Xu was secretly having fun, several roommates were still secretly feeling emotional.Look at them, they are all sophomores, why is there such a big gap.It's really bad to be complacent after reading the textbook.

In the past, I just heard that there are many capable people in Shuimu, but now I see it with my own eyes, and I realize how big the gap between people can be.

They are accustomed to being top academics, they have always been looked up to, and they are desperate big devils.Now I suddenly become a person who looks up to others, how can I be willing, how can an arrogant student allow myself to look up, immediately arouse endless power from the bottom of my heart, I want to do the questions, I want to do 100.

Well, sophomores are still young, and they haven't been used to being beaten by Mizuki. There will always be existences beyond people's normal thinking in such top universities. It is not uncommon for young people to give lectures to old people.

Only by working hard can you truly understand your limits. Whether you finally recognize the reality, or find that you are actually very good, and you are still looked up to by others, the result is a good thing.While Wang Xu had a bad taste, he might not have the intention of motivating them.

Since today's main goal could not be achieved, the brothers simply gave up the idea of ​​doing something today and offered to leave.Wang Xu made a phone call and asked them to bring various materials and bring the circuit to Mr. Yan.

He also formally informed them with a smile that Teacher Yan had something to do with them, and the destination of the taxi was to go directly to Teacher Yan.

Wang Xu didn't know if his smile gave them the illusion of a tight chrysanthemum, but obviously they felt a slight chill, and even the strong Dadong shivered.

Wang Xu hummed and sang songs, and the life of the landlord's family was boundless.

Then he continued with his own plan. He had actually designed a set of power amplifier circuits for his own use. He followed the path of tube tube amplifiers. Anything else, just to look good.

It is also a listening room, if you put a bunch of square boxes, even if there are some LEDs, it will not look so high-end.But once the tube amplifier is released, it needs a sense of ritual of warming up. The faint electronic light during operation, accompanied by music, constantly trembling and changing brightness, looks so high-end and atmospheric, and it is so pleasing to the eye and captivating.

Well, it’s a bit overblown, but tube amplifiers are indeed more fun. Compared with boring transistors, electronic tubes are indeed warmer, which is the common aspiration of most players.Otherwise, just relying on the troublesome use and maintenance of tube amplifiers, and the delicate quality, it is really not as easy to use as transistors.

As for the temperature of the sound, it is very simple, because the electronic tube has a delay, and the delay of different electronic tubes is not consistent, and even the delay produced by the same batch of electronic tubes will have a slight difference.

This delay will cause slight overlap of some waveforms, and because of the difference in delay, the generated waveform overlap will not be exactly the same before and after, which removes the mechanical stiffness.This is where the so-called sense of temperature comes in, which is essentially a flaw rather than an advantage.

Of course, clever use of defects is the ability of music players, so it is acceptable that tube amplifiers can produce a warmer sound.But it's not just tube amplifiers.On the contrary, the tube amplifier can't interpret that particularly clever voice, which is his real flaw.

But for normal vocals, no matter tube amplifier or transistor, there is no problem at all, you can use whichever you like.Wang Xu dares to say that the one you like is the best, and it's useless for others to say that it's broken.

Wang Xu had already handed over the printed circuit to be used by the factory for manufacturing, and received the finished product earlier, even earlier than the arrival of other parts.

Wang Xu even customized a set of all-aluminum alloy casing, which was an extremely extravagant behavior in the 20s.

As for the materials brought back to the students, they are still used to gain reputation, Professor Yan will understand.The principle I use is the same, but I am more focused on the frequency band used for audio.

Today is everything is ready, just assembled.

It's a pity that some time ago, I was so busy that I forgot to make the speaker box early, so I had to wait for the box if there was an empty power amplifier.

Wang Xu's hands are fast, and his welding skills are pretty good.This is nothing special, just like a skilled worker, if you ask him to weld the Galaxy machine, he will definitely not dare.

So the parts that had been prepared were quickly assembled, and a device with a silver-white casing and seven large and small electronic tubes exposed appeared in Wang Xu's workshop.

These electronic tubes are not ordinary, they are produced in the Soviet Union, well, it seems that they will be gone in a few days.Alas, the end of an era, reliving it once did not stir up any waves in Wang Xu's heart.

Only when I saw the huge electronic tube with Russian words and five stars printed on it, I felt a little fluctuating. It was wild, beautiful, and powerful, just like the Soviet Union that was about to pass away.

After connecting the circuit and turning it on, the electronic tube lighted up slowly, the sense of ceremony was full, and the start-up test passed smoothly.

"Beautiful", Wang Xu couldn't help admiring. Although it was designed by himself, the result still surprised him.

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(Today's four chapters, so far)

(End of this chapter)