The essence of wireless communication is to control the frequency of electromagnetic waves.

As long as the current fluctuates, a corresponding change in the magnetic field will be generated, in other words, the first thing Xia Fan has to do is to make the electrical energy of the streamer change rapidly—or tremble.

And the detailed control of the other party's technique has already matured in more than a thousand repeated performances.

It only took him two days before he let out a high-pitched whistling with his new streamer. This "sound" has an extremely high frequency and will not be captured by the human ear, but in the electromagnetic background, it is like a turbulent ripple, with Fengyang Villa as the center, and instantly spreads out to the surroundings of Qiguo.

Xia Fan witnessed all this through the swinging magnetic needle.

Like the Earthquake Justice, this new technique based on the Streamer Technique should also have a distinctive name.

He named it "Xunyin", which was taken from the second half of a seminal electronic hit.

The next step is to make the artifact.

This is also the revelation given to him by Mo Yun's Heavenly Motion Instrument - Xia Fan definitely doesn't want to be the only one who can perform this technique, otherwise he will have to stay at the dispatch office when he has anything to do, and become a part of the communication device. In that case, how can there be time to tease the fox demon?

And Mo Yun also spared no effort in teaching the manufacture of magic weapons, almost teaching him to carve out the first seismic magic weapon of the sound technique.

The trick is to condense the qi on your fingertips, carving the talismans while concentrating your mind on the effect you want to express.

It's all about ideas.

The clearer the idea, the higher the final yield.

This is also the key difference between the carpenter carving the sculpture and the alchemist carving the magic weapon.

And the talisman chosen by Xia Fan is naturally an oscillation circuit - it is only composed of a power supply, an inductor and a capacitor, representing the most basic principle of resonance, after all, no matter how advanced he is, he can't draw it. In addition, the place that should have been the power supply was replaced by his Streamer Talisman, and on this artifact, the essence of the two eras can be said to have been combined for the first time.

"Okay......" Ning Wanjun put down the magic weapon and circled around the equipment he had prepared a few times, "How do you prove that it can ...... Well, teleportation?"

"Just wait. Xia Fan said calmly, "I have asked Li to go to the Privy Council, where she will contact us." ”

"The Privy Council?" the princess glanced in the direction of Jinxia City, "I shouldn't be able to hear the shouting at this distance." So...... What will I see, a note that appears out of thin air, or—"

Just as she was halfway through her speech, there was a sudden sizzling sound from the receiver.

Then, Li's familiar voice sounded in front of everyone, "Xia Fan...... Can you hear me......? That's how this thing should be used, right? What if...... Wow...... Do you remember to get back to me as soon as possible......"

The voice was choppy and accompanied by a noticeable murmur, but even so, it was indeed Li speaking!

This scene made everyone present look stunned!

Xia Fan unhurriedly drove the Xunyin instrument, turning his voice into high-frequency radio waves and sending it out, "I heard your voice." ”

After a brief pause, the voice came from there again, "That's it...... Wow...... That's it. ”

When Li's voice landed, the scene suddenly exploded!

"Is this true? Miss Li is in Jinxia City now?"

"It's three or four miles from the villa to the Privy Council!"

"The thing that made the sound seemed to be this cover—"

"Lord Xia, can only Fang Shi use it?"

There are people who can't believe it? There are people who are looking for Li everywhere? There are also people who ask Xia Fan questions...... For a moment, the front of the lobby became boiling.

"Alright. "It wasn't until Princess Guangping opened her mouth that everyone stopped talking?" If I'm not mistaken, there are spells in the Sunshu that can amplify sounds several times, but the distance is extremely limited, and you can't talk back and forth like you do. Xia Fan, how exactly does this thing do it?"

In fact, Ning Wanjun's shock in her heart at this moment was no less than that of others? If it was only her and Xia Fan present, she probably wouldn't be able to hold back and ask to experience it.

Now that there are so many people watching, she has to continue to maintain the dignity of the princess, and asked calmly.

"Seismosis can turn sound into an invisible electromagnetic signal, and with the right equipment, it can be restored to sound? That's the basic principle of a sound camera. Xia Fan explained succinctly.

"Electric ...... What signal?"

The people were stunned when they heard this, obviously this was beyond their comprehension.

Xia Fan didn't plan to go into details, because this is not something that can be explained in one or two sentences. The effect of the spell depends on the consciousness of the caster, which is also the key to making the current oscillate according to his own thoughts, thus skipping the two thresholds of wired communication and wireless telegraphy.

Shocks aside, the receiver is something completely unrelated to alms. It was a simplified version of the ore radio, which used pyrite as the core of the detector, which could convert electromagnetic waves back into oscillating currents, and through the interaction of copper wire coils and magnets, it was reduced to the speaker's voice.

It can't be FM, it doesn't have filtering, it makes it a constant noise when it transmits information, and the sound quality is just as good as being able to hear what the other person is saying. But it's such a thing, and it took a lot longer than researching a new method. Just a suitable piece of pyrite made Xia Fan rummage in the blacksmith shop for several days.

Ore radios were popular in the streets of the motherland in the 60s, and parts could even be bought in commissaries. Even so, piecing together a simplified receiver from the materials at hand really cost him a lot of brains.

Fortunately, after repeated attempts, the first principle machine finally met his most basic requirements.

"Ahem...... I'm not asking about the principle. Ning Wanjun immediately realized that her way of asking questions was wrong, and immediately changed her questioning, "Do you have to be emotional people to communicate with each other?"

"It is necessary to send a message, but not to receive. The sound emitted by a single telegraph can be heard by multiple receivers. "The biggest advantage of the ore radio is that it is easy to use, and it doesn't even need a power supply.

"How far can this sound travel?"

"It's only a few dozen miles at the moment. Xia Fan estimated it, after all, the audio instrument and receiver are quite simple, and there is still a lot of room for improvement in the future, "When it is fully formed, it should be no problem to spread throughout the Great Apocalypse." ”

In fact, not to mention the Great Apocalypse, even the Six Nations will be shrouded in invisible electromagnetic waves.

"That'...... What are its limitations?" Ning Wanjun couldn't help but clench her hands and said. A magic weapon that can transmit sound for thousands of miles and can be replied to at any time is definitely something that the army dreams of. The situation on the battlefield is changing rapidly, and whoever can gain an advantage in intelligence will be able to seize the opportunity greatly!

"There are no restrictions other than those who feel the breath. ”

"It has nothing to do with the terrain, the weather, the day and night?"

"Yes. Xia Fan affirmed that as one of the epoch-making products, how could radio be such an inconvenient thing?

"I see. Ning Wanjun raised her head and patted him on the shoulder, "The proposal you said at the meeting before, try to make a charter." ”