Otaku Engineer in Great Tang Dynasty

"Your Majesty, Madam, if you two listen carefully, you will find that this telegraph machine can actually make two sounds, one is such a short sound, and the person on the other side receives this signal and can record it as a point. It is pronounced "di", and there is also a long sound that can last for a certain period of time. The person on the other side can record it as a horizontal line when receiving this mark, and read it as "ta". Your majesty and the empress can listen carefully. Listen!"

Zuifengxuan.

In order to explain the transmission mechanism of the telegraph to Li Er and Changsun, Li Zexuan explained the principle while personally operating the telegraph. In fact, the principle is very simple. It is nothing more than the length of time that the key is closed. The control telegraph sends out two different signals.

"Well, it's true, just relying on these alone, I'm afraid I can't deliver the message, right?"

When Li Er saw Li Zexuan's demonstration, he was surprised by the magic of the telegraph in his heart, and asked questioningly.

"Your Majesty, these two monotonous signals can of course not fully express what the two parties want to express. This telegraph machine also needs to be used with a codebook."

Li Zexuan explained with a smile.

"What is a cipher? You kid won't finish talking all at once?"

Li Er frowned and said displeased, daring to deliberately hold the bridge in front of him, this kid is really courageous~!

"Uh, back to your majesty, the minister just said that the two signals sent by the telegraph can be recorded as a dot and a horizontal line. The minister later combined this point and the horizontal line with each other. Each combination represents a number, such as Say one point and four horizontal lines represent the number "1", and the rest of the numbers can be deduced by analogy, a total of ten numbers, and then the sender can combine the four numbers to represent one word, so that there are 10,000 types Combination method, that is to say, through this method, 10,000 different characters can be expressed! And the corresponding text for each combination is the code book that Xiaochen said!"

Li Zexuan stood with his hand in hand, and talked with a bit of pretense. What this guy thinks is that there is a rare opportunity to act in front of Li Er.

In fact, what he just said is the famous Morse code in modern world history. In 1832, Russian diplomat Schilling produced a machine that uses the deflection of the galvanometer pointer to receive information. Later, after three years of research in 1835, the American painter Morse succeeded in using the "on and off" and "length" of electric current to replace human words for transmission.

Morse code is an early form of digital communication, but it is different from modern binary codes that only use zero and one or two states. Its codes include five types: dots, strokes, pauses between dots and strokes, each Short pauses between characters (between dots and strokes), medium pauses between each word, and long pauses between sentences. Then use different combinations of dots and strokes to represent twenty-six English letters and ten Arabic numerals, which can perfectly realize communication.

Later, Morse code was introduced to China, and it was improved a lot. It was almost as Li Zexuan just said, but on the basis of the original, there were a few more combinations.

Li Er was frowning and thinking, but didn't pay attention to Li Zexuan's beating, otherwise he would have to be rewarded for their big feet. Empress Longsun caught sight of Li Zexuan's expression inadvertently, and she couldn't help but want to laugh.

"That's it! Your kid is really good! But according to you, can't the so-called codebook be changed at will?"

Li Er himself is a man of great wisdom, aside from the electromagnetic knowledge that does not belong to this era, he can still understand these password combination principles alone.

"Your Majesty is so insightful! As your Majesty said, this codebook can be changed at will according to your needs. As long as the two parties sending the message use the same codebook, there is no problem! Officially due to the ever-changing nature of the telegram code, The security of the two people’s messages between them is guaranteed, so that even if the messages they send are intercepted by others, they don’t know what the messages represent when they look at the dots and dashes!"

Li Zexuan heard Li Er's question, his eyes brightened, and the ancients were not stupid. What he has more than them is just some insight.

"Oh~! Don't flatter your kid! Oh, listen to what you just said, can the message sent by this telegraph machine be intercepted by others?"

Li Er was secretly refreshed, but he was smiling and cursing on his face, but he was a little puzzled. When he wanted to come, the message from this telegraph was silent and invisible during the spread. How could it be intercepted?

"Return to your majesty, the telegraph transmitting information is actually equivalent to the military messengers transmitting military information through text. They all have the possibility of being intercepted! All you need is a high-powered transceiver, and then adjust the receiving frequency of the transceiver to Corresponding band, you can capture the telegram information sent by others. Of course, this is only theoretically possible to be intercepted, because the production principle of the telegraph machine is only proficient in the world!"

Nothing can be invincible. Although the electromagnetic waves emitted by the telegraph are invisible and silent, they can still be captured as long as they are properly used. In some anti-Japanese war TV dramas, there are not often some underground parties intercepting and deciphering the enemy's telegrams. !

"Military~~"

Li Er's heart moved, and he muttered to himself. Although he didn't know what the "power", "frequency", and "band" were, it did not prevent him from obtaining other key information. He then reconsidered I went through the telegraph on the table again, and my eyes slowly became hotter~www.ltnovel.com~ This is the artifact of the country! With the telegraph machine, wouldn't Datang be invincible in wars in the future?

He had fought a whole life, and immediately thought of how great this telegraph machine would be if it were used in the military.

"You just said that you are the only one who knows how to make a telegraph machine?"

Li Er squinted his eyes, looked at Li Zexuan and said.

Uh, Li Zexuan's heart tightened, he felt a hint of danger, could it be that he just pretended to be too much?

"Back to your Majesty, it should...should be like this!"

From Li Er's tone, Li Zexuan could not hear anything wrong, so he could only bite the bullet and answer.

"Can this telegraph machine be mass-produced? Can it be used for military intelligence transmission?"

There was no special expression on Li Er's face, but there was a trace of expectation in his heart.

"This...."

Li Zexuan wanted to scold his mother a little, and as expected, Lao Li wanted anything good when he saw it! What a robber!

"Your Majesty, the telegraph is currently only in the experimental stage. His transmission distance and working hours are not stable. The minister can use it to chat with Yu Xi, but if it is used for intelligence transmission in the military, it needs to be used first. Solve its power supply problem, and then its signal transmission distance problem..."

"Chat? You actually intend to use this telegraph machine to chat?"

Before Li Zexuan finished speaking, Li Er couldn't help but interrupt, and saw him staring with a look of cannibalism. If it weren't for the eldest grandson beside him, he would have to pull the sword and chop Li Zexuan to feed the dog. !

"Um, Your Majesty... Your Majesty!"

Li Zexuan secretly cried out that he was going to suffer, but Te Niang was anxious to say that he missed her mouth, this is a pill! The robber is going to eat people!

.........

(End of this chapter)