"Xiao Xuan, why did you abuse King Wei like this? If Your Majesty had known, would he have spared you? ”

In the Strange Pavilion Workshop, after Li Zexuan solved the problem for Li Tai, he was pulled aside by Cheng Yanjin and complained in a low voice.

"It's... Uncle Cheng, where do you start? Why did I abuse the green sparrow? ”

When Li Zexuan heard this, he was stunned for a while.

Cheng Yanjin thought that Li Zexuan was embarrassed to admit it, so he couldn't help pouting and said, "Hey! And that's not much abuse? When did the old man see King Wei before, when was he not dressed up clean and decent, and his instruments were magnificent? Look at him now, what is the difference between him and the ordinary craftsman in your workshop? If he hadn't said anything just now, the old man would have almost not recognized him! In the words of their literati, it is unkempt and unkempt! ”

In order to show that Li Tai was indeed abused, Cheng Biting Jin racked his brains and used a few idioms, but unfortunately he still used the wrong one!

Li Zexuan was speechless for a while, paused for a moment, and then he spoke: "Uncle Cheng, Qingque is participating in a cutting-edge technology research project in the academy, and it has been very hard these days, but all of this is his willingness, how can you always say that I am abusing him?" ”

"Research projects? What research project? Oh yes! That ugly boy didn't come home last weekend, and your aunt was talking about it for a while! Could it be that he is also involved in this research project? ”

Cheng Yanjin's eyes lit up when he heard this, and then he remembered his living treasure son, and hurriedly asked.

"Uh..."

At this time, Li Zexuan was speechless, saying that Cheng Yanjin really looked down on his son, but with Cheng Chumo's achievements and his uncontrollable temperament, how could Li Zexuan arrange for him to engage in scientific research? If you don't tell the truth, the kid may not be beaten again, thinking about it, Li Zexuan can only say vaguely:

"That's it! However, the recent research projects carried out by the academy are all top secret, and no one is allowed to reveal half a sentence to people outside the project, this is a hard and fast rule, and the little nephew cannot make an exception, and I hope Uncle Cheng can forgive me! ”

"Top secret? Why is the project so mysterious? ”

When Cheng Yanjin heard this, he was even more interested, for Li Zexuan's ability to create new things, Lao Cheng was 10,000 convinced, for example, the variable speed disc brake bicycle that he can't put down now, so the project that can make Li Zexuan so solemn must be a good project, so he asked a little unwillingly:

"Xiao Xuan, can't you really reveal a little bit to the old man? Your Uncle Cheng is not an outsider, so it is impossible to tell anyone else, besides, you are the mountain chief of Yanhuang Academy, aren't these rules all set by you? So what's the point? ”

Li Zexuan said helplessly: "Uncle Cheng, just because I am the head of Yanhuang Academy, I have to set an example, if I don't follow the rules, how can I expect the rest of the academy to follow the rules?" So the little nephew really can't tell you about this matter! You can rest assured that this research project will definitely be beneficial to Datang! ”

"It's not! Isn't that equivalent to not saying it? ”

Lao Cheng muttered, but he also knew that it was impossible to ask the truth from Li Zexuan's mouth, so he didn't continue to ask. Seeing the brand-new bicycle pushed in his hand, Lao Cheng's interest was high again, and he laughed and said:

"Haha! Then Xiao Xuan, you are busy! The old man will go back to Chang'an first! I don't want that old bike, this one is enough! Ha ha! ”

It turns out that Lao Cheng is a person who likes the new and hates the old, this old man rode a variable speed bicycle, left the workshop like a gust of wind, and pity the worn-out bicycle he rode over before, so he could only lie quietly in a corner of the workshop and eat ashes!

.................................

After Cheng Yanjin left, Li Zexuan arranged for someone to send the remaining bicycles to Qin Qiong, Wei Chi Jingde, Niu Jinda, and Li Jing's homes, which were the closest to him, and they couldn't forget them if there were good things. In addition, Li Zexuan also sent Liu Feng and Liu Yun to send three gear-shifting bicycles to the palace, which were given to Li Er, Li Chengqian and Changle.

After Changle was cured, the whole person was more lively and active than before, and now it is just right to give her a variable speed version of the bicycle!

"Qingque, the teacher suddenly has an idea, is it feasible for you to listen to it?"

After everything was arranged, Li Zexuan came to a courtyard in the deepest part of the workshop, found Li Tai, who was modifying the telegraph, and said.

This annex is the secret research base of the second and third killer projects of the academy, and there are Li Zexuan's personal guards outside the courtyard day and night, and all personnel must verify their identities when they enter and exit, which can be regarded as a strict guard!

At present, the participants of these two killer projects are being recruited and screened intensely, but this does not affect Li Tai, the deputy chief designer, to promote the relevant work, in just a few days, Li Tai has created simple resistors, capacitors, inductors and other electronic components, plus the electronic diodes and electronic transistors previously made by the workshop, it can be said that the foundation of Datang's electronics industry has gradually taken shape!

"Oh? Chief, please speak! ”

Li Tai, who was busy, immediately put down the work in his hand when he heard this, looked up at Li Zexuan, and said.

has been "messing around" with Li Zexuan for so long, Li Tai knows that Li Zexuan's every idea has the potential to change this era, and he doesn't dare to take it lightly!

Li Zexuan pondered for a moment and said: "Qingque, the telegraph we are making now transmits information through the conversion of electricity and electromagnetic waves, and this kind of telegraph is indeed used in the army to coordinate the situation and anticipate the enemy's opportunities, but if the people have the need for ultra-long-distance communication in the future, the telegraph will be inconvenient!"

So I think we can maybe make a device that can convert sound into electricity, and then convert electricity into sound, so that only one wire is needed to connect it, and we can realize real-time sound transmission at both ends of the wire! ”

This is actually a wired telephone, Li Zexuan has long wanted to do it, but in the past, Datang had no industrial foundation, and he couldn't do it if he wanted to, but now it's different....

These words may sound a bit fantastical to others, but Li Tai did not rush to deny it, he pondered for a long time before he spoke:

"Electricity and sound? Yamana, your idea sounds like a good idea, but in order to put it into practice, the first step is to solve the problem of how to convert these two completely different energies of electricity and sound into each other! ”

Specialized!

I have to say that Li Tai is now much more professional than before, and he can see the essence of the problem at a glance.

Li Zexuan looked appreciative: "Haha! Qingque, you're right! In order to achieve long-distance real-time sound transmission, the first problem is to solve the problem of electric and acoustic conversion! Although they are two different energies, they do not necessarily mean that they cannot be transformed into each other! For example, electricity and magnetism before were not of the same kind, but with the efforts of Miss Mo, can't they also be converted into each other now? I have a preliminary idea here, I'll tell you about it first, and you can think about it privately! ”

"Uh-huh! Chief, please speak! ”

Li Tai nodded hurriedly, not at all discouraged because Li Zexuan wanted to increase the burden on him, he was a natural person who pursued fresh technology, otherwise he would not let go of the free prince, but would have run to the workshop to suffer!

Li Zexuan picked up a pen and paper at this time, and drew while writing: "In fact, it is not difficult to convert electrical energy and sound energy into each other, but a magnetic field is needed in the middle to make an intermediate medium!" You see, we can use this conical paper cone at the front end of the machine to collect sound, you have studied "physics" you should know that sound is a sound wave generated by the vibration of an object, in the same way, when the sound wave hits the paper cone, it will cause the surface of the paper cone to produce small vibrations.

At this time, if we attach a copper coil to the bottom of the paper cone, and then place the copper coil in a permanent magnetic field, when the front end of the paper cone receives the sound, it will drive the coil to vibrate, and the coil will cut the magnetic inductance line, which will produce a current corresponding to the frequency of the sound wave, and we will complete a process of sound wave electricity!

How to convert electricity into sound waves is also simple, and it is also possible to attach a coil to the bottom of the cone and apply a permanent magnetic field, when the current passes through the coil, the corresponding magnetic field is generated in the coil. This magnetic field and the applied permanent magnetic field produce an interactive force, this force will cause the coil to vibrate with the sound current in the applied permanent magnetic field, and the paper cone diaphragm and the coil are connected together, so the diaphragm also vibrates.

Qingque You should know that under the same voltage, the size of the magnetic field generated by the same energized coil is proportional to the size of the current, so when the current through the coil is larger, the more intense the movement of the coil in the magnetic field, and the louder the sound emitted, so the vibration of the coil can produce sound similar to or exactly the same as the original audio signal waveform.

In this way, we can realize the conversion from sound to electricity, and then from current to sound, as long as the wire is long enough and the electrical energy is large enough, our sound can travel far enough! ”

Li Tai was a little stunned when he heard this, in the face of such an exquisite design, he was so excited that he even breathed at this moment, maybe this is suffocating for his dreams!

After a long time, Li Tai finally came back to his senses from the shock, he took a few deep breaths, and then looked at Li Zexuan with the eyes of the monster, opened his mouth, and couldn't speak for a long time!

"Mountain... Yamana, this design is so exquisite! It's ingenious, it's amazing! ”

After trembling for a long time, Li Tai finally spoke: "If it can really be done, then there will be no need for a telegraph machine in the future!" Yamaga, how about we just start working on this machine that transmits sound for thousands of miles and give up improving the telegraph? ”

Li Zexuan hurriedly waved his hand and said, "No! Qingque, what I told you just now is just my idea, from the idea to the product, there is still a long way to go, even if you make it, the audio debugging in the later stage will take a long time, and the improvement plan of the telegraph has been scrutinized countless times by us, and now it is completely natural, never give up the near and far!

And compared to this kind of thousand-mile transmission of sound, the telegraph is not useless, especially for military communications, the telegraph has better secrecy, even if the enemy captures our telegraph, they are useless without a code book! In addition, telegraphs do not need wires to send and receive telegrams, which is the most convenient when fighting a war! So in any case, be sure to get the telegraph in good shape first! ”

Hearing Li Zexuan say this, Li Tai also woke up from his excitement, and he nodded and said, "Hmm! I understand! ”

It's just that his eyes still couldn't help but flash a touch of disappointment, this feeling that he knew that there was a more advanced thing, but he didn't have the time to create it for a while was really uncomfortable for Li Tai!

Li Zexuan smiled when he saw this, he patted Li Tai's shoulder and said, "But although we don't have the energy to build that kind of long-distance sound transmission machine at present, we can build a simple acoustic-electric conversion device first, and it shouldn't take long!" ”

"Oh? What do you say, mountain chief? ”

Li Tai's eyes lit up and he hurriedly said.

Li Zexuan smiled: "Just because I want to make a small thing, Qingque, you can help the teacher make it!" This thing is to use the paper cone diaphragm to convert the human voice into an electric current, and then use a triode to amplify the current, and the amplified current flows through the coil, and then through the action of the magnetic field, it vibrates with a more violent amplitude, so that the sound is even greater! I call this a loudspeaker or a loudspeaker, it's much simpler than a long-distance sound machine, if you have the time, try to make one! ”

Li Tai thought about it in his mind, and then said excitedly: "This is a good idea!" The amplifier is simple to make, but the principle is similar to that of the long-distance sound transmission machine, if this thing can be made, the machine that will make the long-distance sound transmission machine in the future will be more confident! ”

Li Zexuan nodded and said, "That's exactly the truth!" ”

After that, he looked at the shadows of the trees outside the house and said, "Okay! Then let's do it first, Qingque, you are busy, I'll go first! ”

Li Tai hurriedly bowed down and said, "The mountain chief walks slowly!" ”

After experiencing this incident, he admired Li Zexuan even more, it was simply a mountain looking up, a view of the line, although he couldn't get there, he yearned for it!

.................................

"Your Majesty, His Royal Highness the Crown Prince asks to see you!"

Around the time of Shen, the Imperial Palace, the Hall of Ganlu.

After reviewing the music for a while, Li Er, who was dozing off with his chin, was suddenly awakened by a shrill voice, who else could it be if it wasn't Zhao Song? Speaking of this kind of "special" moment, only Zhao Song dared to come over to tell the matter.

"Oh? Cheng Qian is here? Let him in! ”

Li Er rubbed his sleeping face and cheered up.

"Oh~!"

Zhao Song took the order and left, and at the same time couldn't help but breathe a sigh of relief in his heart.

After a while, Li Chengqian came in, and he didn't come in alone, and there were still .... Pushed a car!

Seeing this scene, Lao Li suddenly lost any sleepiness, and without waiting for Li Chengqian to salute, he said, "Chengqian, why did you push a bicycle in?" Well? Wrong! This bike seems a little weird......."

...........................