Once We Lived in Nanjing

Wang Ning's voice had barely fallen when the 725 amateur radio on the coffee table began to radiate electromagnetic signals outward. It converted images into sounds, and then hid the sounds within radio waves undetectable by human ears—a murmur of whispers incomprehensible to mankind. Yet amazingly, it was actually an image—turning an image into sound may be unimaginable to the average person, but to those who have mastered the technology of information encoding, information is information, and the medium is the medium. As long as one could see through the essence of information, separating it from the medium was not a difficult task—at all. Since tens of thousands of years ago, when humans first carved wall paintings into cave rocks, the image, as the carrier of visual information, has progressed from rock walls to clay tablets, canvas, straw paper, and photographic film, enduring the vicissitudes of time over millennia. Their relationship seemed eternal, unchanged since time immemorial, until the flames of the Industrial Revolution ignited, information theory brought about world innovation, and humans finally could lift image information out of the two-dimensional plane, stuffing it into sound, into electric currents, into light waves. From then on, any information could be broken apart, ground down, and stuffed into any medium.

Understanding the essence of information, in a sense, is also the power of God.

By mastering information, mankind has taken another step towards divinity.

Bai Zhen sat in front of a laptop screen, watching a photograph slowly appear from top to bottom—a feeling akin to what? Like a lottery drawing, a scratch card, scratching off line by line to reveal the picture underneath.

Initially, the signal was poor, and all that was scratched out were green snowflakes of noise. It was only after Bai Zhen slightly adjusted the direction of the antenna that he could receive a clearer picture.

"How's it going?" Wang Ning asked.

"Not bad," Bai Zhen responded. "It's just a bit slow."

A half-body photo of a Ugandan baboon... pah, a mandrill, was 15KB in size, and the transmission speed between the 725 and 705 in the living room, being used for this analog experiment, was only about 1000bps—that is, 0.1KB per second. Ideally, to transmit such a photo completely, it would take 150 seconds, or two and a half minutes.

But when are things ever ideal?

After all, radio is radio, not cable fiber optics. It's convenient to use radio waves to transmit signals, yes, convenient, certainly simple, but one cannot expect it to be very efficient.

Convenience, simplicity, and efficiency—you can only have two of those at once.

So amateur radio image transmission is unstable; in the context of network engineering, it's equivalent to severe packet loss. If the antenna isn't aligned just right, what's scraped out is just a strip dotted with green snowflakes. Hoping to successfully receive a complete, clear picture in one go is impossible.

To ensure complete signal transmission, Wang Ning's end would send multiple redundant signals. His 725 would transmit the picture repeatedly in cycles of 150 seconds until Bai Zhen could receive a complete picture. So, in Bai Zhen's eyes, the Lenovo computer in front of him was repeatedly scratching off a lottery card, with a complete picture of himself equating to hitting the jackpot.

"Wait... There's interference, where is it coming from?" Bai Zhen scratched his head, looking around. "Is it the switch? Hold on, Lao Wang, I'll go turn off the main switch and try."

He immediately ran to turn off the power breaker, cutting the electricity and plunging the room into pitch darkness.

"Is there a power outage?" Mom, holding a cellphone flashlight, came from the bedroom. "Why did it suddenly go dark?"

"Lao Bai turned off the power," Wang Ning sat on the sofa, his chubby face illuminated by the eerie green light of a CRT monitor. "We're doing an image transmission experiment."

"You have to do your experiment, but why pull the switch?" Mom asked.

"There's interference," Wang Ning replied.

Annoying electromagnetic interference is everywhere in modern society. For instance, the tower crane at the construction site next door, the security walkie-talkies at the community's entrance, electric vehicles downstairs, and many seemingly insignificant small electrical appliances used in daily life, such as in-house power switches—interference is pervasive, omnipresent in full 3D audio, impossible to avoid. Bai Zhen could only turn off his own home's electricity, not that of the neighbors, and certainly not that of Meihua Villa's—the electromagnetic environment in the city has deteriorated to this state.

Some veteran HAMs like to operate portable—ah no, field setups, craving that pristine, boundless environment where a good signal-to-noise ratio allows them to hear even the sound of a fly rubbing its hands at the other end of the radio waves.

After the power was cut, Bai Zhen tried again to receive the signal.

"Any better?" Wang Ning asked.

"Not at all!" Bai Zhen said. "It's the same crap."

"Go find the community's main switch," Wang Ning suggested. "Turn off all the power in the community, then the interference will be gone."

"Then wouldn't the property management skin me alive?"

"Hey, special reasons for special times, right? Just tell them it's an emergency requisition of power, Unit-01 is on Zijin Mountain using the Positive Electron Cannon against the fifth Angel Envoy, if they don't supply power now, Ayanami Rei will die."

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Bai Yang, wrapped in a hoodie, sat in the dark, the radio connected to a battery, with a desk lamp turned on. Warm light fended off the night, creating a small circle encompassing the desk, pen holder, radio, and the face of the youth. He held the microphone in one hand and a pen in the other, concentrating, writing furiously.

"Hm? It's nothing, just the lights went out, that's all. My old man and the others pulled the switch," Bai Yang said pressing the PTT button to talk. "They're doing an image transmission experiment, Miss, let's continue... Do you know about Newton? Newton's law of universal gravitation, OVER."