Yang Gan looked at the wooden box covered by black cloth, smashed it down his mouth, and said strangely, "What is this?"

Everyone also showed curious expressions. After all, Zhang Yumeng invented many useful things, and even many things were silently affecting the pattern of the times.

For example, allicin is so terrifying on the battlefield, it is no less than the elixir of flesh and bones of life and death.

"Hehehe~~~!"

The candlelight reflected Zhang Yumeng's expression very sinister, and combined with her rippling laughter, she looked like a big villain.

"Ahem."

She cleared her throat, grabbed the black cloth, and said loudly, "Since you have asked sincerely, I will tell you with mercy, in order to prevent the world from being destroyed and to maintain world peace..."

Suddenly, Yang Gan interrupted and said, "Hey, it's almost done, you're exposed to your age."

This sentence almost made Zhang Yumeng choke to death. She glared at Yang Gan with hatred.

There was a "swish".

He lifted the black cloth away, and introduced with both hands to the big box in front of him, "Dingdeng~~~!"

“This is what I made——the wireless phone!!!”

"bass!!!"

Yang Gan suddenly stood up, staring at the unpretentious box in front of him, and his breathing gradually became rapid.

Cao Wushuang, Chrisna and others had no idea what was going on, but judging from Yang Gan's expression, this must be a rare treasure.

Yang Gan hurriedly stepped forward a few steps and rubbed the surface of the box with his very gentle hands. It was a plastic shell.

For a long time, Yang Gan always thought that he would be very happy as long as he could make a phone call, but there was a problem with the phone, which was to line up.

Although the telephone line is very thin, it is also made of copper inside and needs to be buried underground. The distance is long, whether it is materials or manpower, it is a huge project.

But unexpectedly, Zhang Yumeng gave her a huge surprise. In this way, she saved countless time, countless materials and countless manpower.

Seeing Yang Gan lose his composure, Zhang Yumeng shrugged and said with a hilarious voice, "You are too exaggerated. Isn't it just a radio? If it weren't for the materials that you had to make, put them in your previous life and make them for you in minutes."

Everyone knew the conversation between the two, and everyone never understood it.

Yang Gan lowered his head and kept shaking his head. Suddenly he turned around and his face turned red due to excitement.

"What do you know?"

Yang Gan put his hands on his claws and raised them to his chest, and a blurred light burst out in front of his eyes.

"This is the real artifact. In modern wars, those who get it can win. It is the strongest weapon in the evolutionary history of mankind in 2 million years."

Seeing Yang Gan's exaggerated expression, Zhang Yumeng twitched hard, leaving a drop of cold sweat.

"Brother, it's so exaggerated. I just made a wireless phone, not a nuclear bomb."

Yang Gan said disdainfully, "Do you think nuclear weapons are the strongest weapon of mankind? Wrong, it's a big mistake. The power of nuclear weapons is great, but who can use this thing in conventional wars? At most, it is a deterrent method."

"The strongest weapon of mankind in 2 million years is communication technology."

"Think about it yourself. I can get the latest information first, and no one will be able to get out of my palm."

"If there is a rebellion in a place, he must prepare food and grass and gather personnel. Maybe before the departure is reached, he will make a phone call and give a few orders. Before the traitor is ready, hundreds of thousands of troops have surrounded him."

"You can also imagine that when there is no way for the army to fight thousands of miles away, you can ask me directly. Countless think tanks can help you come up with ideas. With this thing, there is no way to avoid military orders outside."

"What is this? This is the magic weapon of the country - mobile phone!!!"

Compared to Yang Gan's fanaticism, everyone narrowed their eyes and looked confused on their faces.

"Mobile phone? What is that? Is it a machine that can be cultivated?" Ran Jing looked curious. After all, the thing that you like most is a machine that is helpful for cultivation.

Yang Gan laughed and said, "Mobile phone, in terms of what you can understand, I can talk to people far away in Wanghai County in Yuntong through this box, and people in Wanghai County can also talk to me through this box."

...........

Everyone took a breath and widened their eyes. No one present was stupid Bai Tian, ​​and they had more or less knowledge of war.

Cao Wushuang is skilled in bowing and horses. Although he has never been on the battlefield, he is well aware of this.

Needless to say, Ran Jing is like a battlefield killer.

Krisna and Bailika both came from fighting countries, how could they not know the value of this thing?

Cao Wushuang was dumbfounded and murmured, "Can you speak from a very far distance? Is this a magic trick?"

"I think it's like a witch."

"Can you really make something like this?"

"I really want to try it out, so I'm looking forward to it."

"Oh roar~~~!"

Yang Gan immediately asked, "Is there any of this in Zhuangzi? Can you answer the phone with Xiao Yu?"

Zhang Yumeng smiled and said, "No, of course, there is. Although it is still difficult to produce large-scale products now, the assembly line of each component has been implemented, which is that the output is small, and the scrap rate of vacuum tubes is a bit high."

Yang Gan waved his hand indifferently, "It's just a few small defective products. It's okay, I can afford to waste it. By the way, how far can this thing be controlled?"

Zhang Yumeng frowned and said, "I haven't tried this yet. Radio is theoretically infinite, but there are still distance limitations due to the influence of radio wavelength, dielectric loss, receiver sensitivity, transmitter power, and Earth's curvature."

"Generally, the distance of microwaves without relay transmission is 40-50 kilometers. Short waves can propagate to hundreds of kilometers through ionosphere reflection, but they are very unstable due to the ionosphere changes. Long waves can generally propagate to places thousands of kilometers away."

"If it is not enough, you can build a relay station, which can enable microwaves to be transmitted beyond the visual range."

"The function of the relay station is to amplify and shape the received signal. In order to reduce the influence of the curvature of the earth, microwave relay stations are generally built on the top of a mountain or to erect relatively high transmitting towers, which was found in previous high school textbooks."

"But then again, I know the relay station, but judging from the current technology, it is quite difficult to achieve it in a short period of time. Moreover, that thing is too conspicuous. In such a place without monitoring, it is easy to be destroyed."

Yang Gan clenched his fists. Although Zhang Yumeng didn't understand what he said, the last sentence was to understand. A relay station was built in a desolate place, without surveillance or other things, and it was destroyed by people or beasts in minutes, and it was not easy to repair.

"Then, if you say, how far can you usually support calls?"

Zhang Yumeng rubbed her hands and thought, "The 0.5W walkie-talkie sold on the market, the manufacturer's nominal maximum call distance is 3 kilometers. This call distance is only a theoretical calculation data."

"Its basis is the transmission power, that is, the maximum call distance for a 0.5W walkie-talkie without obstacles and electromagnetic interference."

"In actual use, due to the different environments of users, the background noise is large and small, and the electromagnetic interference is strong and weak, the actual call distance is generally less than 3 kilometers."

"Many users often mistakenly think that when purchasing walkie-talkies, the call distance can reach 3 kilometers when they use it in the city. This is unlikely. The manufacturer cannot predict the user's use environment, and of course it is impossible to give the actual call distance."

"Of course, our environment is very good now, there is no messy radio wave interference, nor high-rise buildings. It's amazing that it is subject to the terrain. However, most of the north are plains, so the problem is not big."

"The general data is almost the same as 5-watt professional machine that can support distances of 2000-5000 meters, 2-watt handrail supports 1000-3000 meters, and 0.5-watt civilian machine that can support 200-1500 meters."

"Ba~!"

Yang Gan said excitedly, "Isn't that not? Just increase the power and expand the distance, right?"

Zhang Yumeng nodded and said, "In theory, this is the case, you can wait a moment."

She ran out of the tent quickly, and soon she saw two soldiers of the black armored iron cavalry walking in from outside with a bobbin-shaped metal rod.

Judging from their expressions, it is obvious that this thing is not light, but on the contrary it is a bit heavy.

"Take it lightly, don't knock it~~~!" Zhang Yumeng stared at the two soldiers carefully, and kept reminding her.

The two soldiers were also big and round waists. Although they were heavy, they were still a little bit of a problem. If they weren't afraid of ruining this thing, they could have any one of them.

After carefully putting the thing down, the two of them bowed and went out. Zhang Yumeng pointed to the bobbin metal rod on the ground and said.

“That’s what the supporting components of the wireless phone.”

Yang Ganqi said, "What is it? It looks so weird. Tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk tsk t

"Cut, what's the point of a little metal? The parts inside are made of brass, pure brass, and some aluminum."

Yang Gan's mouth twitched hard. Copper is a common thing in modern society, but you must understand what it meant in ancient times.

Coins are made of copper. To create such a thing is to use money to create something.

"What's the purpose?"

Zhang Yumeng smiled and said, "You think, if the power of the wireless phone is adjusted too high, it will be quite a pressure on the internal components, but if it is appropriate and does not damage the wireless phone, it will only be 50 to 100 miles away."

"For example, from Yuntong County, at least seven strongholds must be arranged, and different persons in charge will transfer one sentence to the final destination. Although the time has completely surpassed the transmission."

"But the disadvantages are also very huge. If it is just a sentence, that's simple. But if it's a report, wouldn't it take a lot of records? Over time, there will definitely be a possibility of a record error."
Chapter completed!