Working Prophet.

Chapter 331

The handheld walkie-talkie that Li Yu brought to the green field before has a transmission power of 5 watts. The effective communication distance of this kind of walkie-talkie is about 1 to 3 kilometers in the urban area, and 3 to 5 kilometers in the wild.

In the green field, this number can be doubled again, because compared to another cosmic plane, Bratis Continent has a better electromagnetic environment.

Except for some electronic equipment brought by Li Yu and Xiaowa, there is almost no environmental noise here, but even so, it can achieve Unicom within 15 kilometers at most.

After Clara was kidnapped, in order to find her, Li Yu sent a team of Black Dog Guards headed by Tom. However, after Tom left the green field, the two sides could only rely on traditional manpower or carrier pigeons to pass messages.

In this way, there is considerable lag, and there is also the risk of being intercepted halfway.

In addition, once Tom started to move and changed his mailing address, Li Yu could no longer keep in touch with him until he sent a letter next time.

So Li Yu began to consider establishing a longer-distance communication method.

The most intuitive way is of course to increase the transmit power.

For example, increasing the transmission power from 5 watts to 50 watts can increase the effective communication distance by almost five times.

But even so, the longest communication distance is still only 75 kilometers.

In addition, there is a more common way to add repeaters.

The role of the repeater is to relay and amplify the signal.

This is a bit like a relay race. When you are about to run out of strength, you can pass the baton to a taller and faster person, and let him help you continue to run, so that you can run farther.

But unless the IP repeater is directly connected to the IP network, the communication distance that can be improved by setting up the repeater is still very limited.

In addition, the biggest problem with this method is that the relay station must be set up outside the green field, which will inevitably require additional manpower and energy to maintain the equipment.

Since neither of these two methods is satisfactory, are there other solutions that can meet Li Yu's current needs?

The answer is yes.

That's shortwave radio.

In the movie "Eternal Waves", the protagonist Li Xia uses a short-wave radio station, which can send telegrams from Shanghai to Yan'an.

This is because the propagation path of short waves includes sky waves as well as ground waves.

The signal can be transmitted to the sky through the antenna, reflected back to the ground by the ionosphere, and then reflected from the ground to the sky. After multiple reflections, a signal whose ground wave can only travel tens of kilometers can be propagated to hundreds or even tens of thousands of kilometers away .

In the early spy wars, most of the short-wave radio stations equipped by intelligence personnel used CW communication and relied on Morse code to transmit information.

Until now, there are still many amateur radio enthusiasts who are obsessed with using this method to transmit information, and have even been able to achieve 1 watt to pass the world.

However, Morse code needs to be learned, and the corresponding English letters, for people on the continent of Bratis, the learning cost is even higher.

Fortunately, the times are developing. In addition to CW, there is now SSB mode, which can directly transmit voice.

Li Yu bought three Yaesu shortwave radio stations, and then joined a WeChat group full of ham radio enthusiasts on the recommendation of his boss.

With the help of the big guys in the group, it took about three days to learn the basic usage of the radio, and then taught Radio in the green field.

This led to the birth of the first half-baked radio operator on the continent of Bratis.

It's not that Li Yu doesn't want to train Ledio to be more professional, it's mainly because he is only half full.

Fortunately, the opponent is at least hundreds of years away from understanding this technology. Thinking about it this way, Li Yu feels much better.

Looking at Ledio, there is no such trouble at all. Although this kid is better than him, he doesn't know it. Li Yu taught him for two days, and he already has the posture of Wang Chongyang leaving the customs. .

And there is a reason for Radiodio's pride. In terms of radio technology, he is indeed the second in the world in this plane, second only to Li Yu who is the number one in the world.

Even Li Yu couldn't refute this point.

What's more, the first actual battle with Radio did not lose the chain. Hearing the prayer sound from the radio, Arvo ran outside the house immediately and found Li Yu who was doing maintenance on the tractor in the yard.

Li Yu put down the remaining half bottle of lubricating oil, wiped his hands, and walked into the room.

"Ah, is it Radio, can you copy it?"

"I'm Ledio, Master Prophet, you can copy it, you can copy it." Ledio's voice was trembling with excitement.

Li Yu was also in a good mood, because Radio's voice sounded very clear, without the clutter interference that the bosses in the group complained about.

"You should have arrived in Multi-Lined City by now." Li Yu continued.

"That's right, we're just outside the multi-scaled city right now, my lord prophet." Redio said respectfully.

"Very well, hurry up and enter the city. According to the news from Yanxue City, in a few days, High Priest Martina and her cathars should also arrive."

"Actually, this is the reason why I called you. Regarding entering the city, we have encountered some trouble. In order to prevent the spies of the cathars from sneaking into the city to make trouble, Multi-scale City is no longer allowed to freely enter and exit."

Radio said, "Now only those who have a pass issued by the Raimondi family or the Silvermoon Church can pass through the city gate."

"Ha, I thought it was a big deal, it's simple."

The person who spoke this time was not Li Yu, but another voice.

Li Yu brought a total of three radio stations this time, one set up in his residence, one handed over to Radio, and the remaining one, Li Yu put it in Teacup Fort.

It is mainly for the convenience of Miss Rabbit to contact him if there is any urgent matter.

As a result, Li Yu regretted it as soon as the fight was over, because Ilea ignored the conditions of what he called "urgent matter".

After I have a new toy, I like to call him on the radio when I have nothing to do.

"Is Merlin, Merlin there?"

"Ok?"

"I saw a purple sparrow when I went out today. It was so beautiful. I don't know if I can see it tomorrow."

"........."

Or "Meilin, Meilin, are you there? I had carrot stewed pork for lunch. What did you eat?"

There are also speeches such as "My ancient spirit has been upgraded to level 95, it's amazing!"

Li Yu had no choice but to temporarily turn off the radio station over there again.

But he obviously underestimated the female lord a little bit. The latter didn't know if it was because the electronic pet egg played too much.

After Li Yu turned off the radio, the female lord was able to turn it on secretly.

And these three radio stations use the same frequency, so the female lord should have heard their conversation just now.

That's why I couldn't help but interrupt.

(End of this chapter)