Once We Lived in Nanjing

Remote control system construction completed, the next item on the agenda is the image transmission link.

Over the weekend, Wang Ning and Bai Zhen discussed in detail the technical essentials of using the Icom725 amateur radio for image transmission.

"Using a camera, right?" Ban Xia squatted on the living room floor, holding a UV9R walkie-talkie in her hand, surrounded by a mountain of cameras, "I've brought back so many cameras, I might have emptied Zhujiang Road."

In the past week, the girl visited Zhujiang Road daily, scavenging a massive amount of electronic waste.

LCD monitors, computer towers, motherboards, coaxial cables, cameras, mice, keyboards, both useful and useless, familiar and not, all stuffed in sacks and dragged back with a small trailer.

This is a world of ecstasy for a junk collector.

"I have so many cameras here, which one should I use?" Ban Xia asked.

After the remote control system was established, communication indeed became much more convenient, the most noticeable change being that the girl no longer had to squat constantly in the room.

She could walk around the house with the handheld station.

"Best to use a UVC camera, OVER." Bai Yang's voice came from the handheld station.

"BG4MXH, what is a UVC camera?"

"UVC stands for USB VIDEO CLASS, a standard protocol," Bai Yang answered, "Simply put, it's a driver-free camera, plug and play, very convenient, OVER."

"Then which one is the UVC camera?"

Ban Xia randomly picked through the pile, there were so many cameras: half-spherical ones, cylindrical, rectangular, and even some that looked like small desk lamps with stands.

"Most web cameras are UVC cameras; those you found are all them," Bai Yang said, "Just pick one that still works properly, OVER."

Establishing an image transmission link is much more complicated than the remote control system.

Wang Ning said that a pure analog relay station like GR3188 doesn't have much difference from the 725 at the communication protocol layer as it essentially consists of two base stations, both are one family, speaking the same language, as long as the hardware path is correctly constructed, the relay station and the rest can awkwardly fit together to get the whole chain running.

But image transmission is different.

The image data collected by the camera needs to be sent to Bai Yang through the relay system, but the network camera and the amateur radio are not from the same family: the network camera is a new-gen product while the amateur radio is an antique. They utterly speak different languages, unable to understand each other; thus, they need a powerful translator, a core machine, a connecting hub to take on the transcoding function.

Converting image data into a signal that amateur radios can transmit, the undoubtedly best candidate for this task is a computer.

The computer is the most convenient and simultaneously the most powerful platform, as long as Ban Xia can find a computer that works properly, all problems will be solved.

"It's no use, these computers are useless." Ban Xia shook her head, "All rusted beyond recognition, don't even respond when plugged in… oh my!"

She suddenly exclaimed.

"What happened? What's the matter, miss?"

Several seconds later, the girl responded:

"It exploded, this motherboard exploded, smoke billowed out, cough cough… I'm going outside to avoid it."

Unable to find a usable computer, Wang Ning and Bai Zhen settled for a secondary option, discussing the feasibility of development boards and Raspberry Pi in this system.

"What system does the Raspberry Pi use?" Wang Ning asked.

"Linux," Bai Zhen answered.

"Are you skilled at developing on the Linux platform?" Wang Ning asked.

"I'm best with microcontrollers and DOS, you know the old equipment in the military widely uses DOS," Bai Zhen said, "I know a little about Linux."

"To what extent?"

"I can spell it."

Ban Xia ran to the balcony, opened the window to let the night breeze in, then leaned on the balcony and gazed out leisurely.

"I feel like my life has meaning again," she suddenly said.

Bai Yang was stunned.

"Why do you say that? OVER."

"Before getting in touch with you, I was just living day by day; I didn't know why I was still in this world or what I was supposed to do. After Teacher left, I lived alone in the house. I would sit all day long without speaking, and gradually, I even forgot how to talk because there was no one to speak to. But I can't just talk to myself, right? Constantly talking to myself would drive me insane, so I forced myself to sing," Ban Xia said. "If I didn't sing, I would have turned mute. Luckily you contacted the current me. If it was two years later, I could only speak to you like this: Wuu wuu! Wuu wuu!"

She giggled.

"But now I find life so interesting. Finally, I have something to do, whether it's going to Zhujiang Road to pick up trash or modifying the relay stations and 725. Before going to bed at night, I can think about what I'm going to do tomorrow. Life is wonderful; I love it so much."

"Erm... Don't you find all this quite troublesome and boring?" Bai Yang asked. "Don't you get tired of it? OVER."

"Not at all," Ban Xia said.

"Miss, you still have to learn programming later on, so don't speak too soon," Bai Yang cautioned. "That is even more boring and difficult, OVER."

"Bring it on!"

Ban Xia was full of confidence. What could be more difficult than the life she had lived before?

—Two days later, she was rolling on the ground:

"I can't do this anymore! It's just against me! This is unscientific! This is incomprehensible! The code I entered is clearly correct, so why won't it run?"

"BG4MXH, after the image transmission link is established, what data do you need?" Ban Xia asked. "We can only get in touch at 10 PM, and it's already dark outside. What can we capture?"

"We're still discussing that," Bai Yang replied. "Miss, image transmission isn't the key point. The priority is to expand the data transmission link. Currently, we can only communicate through radio voice which is too limiting. We need to lay the groundwork first. Once the road is paved, we can drive bigger vehicles. Do you understand? OVER."

The girl nodded.

She could understand what Bai Yang was saying, but she didn't know what else they could do once the data channel was expanded.

It was clear that Ban Xia knew almost nothing about the past apocalypse disaster.

Additionally, very little information about that disaster remained in the world. Human civilization was destroyed comprehensively in a very short time, with seven billion people vanished without a trace, leaving only the wreckage of planes, scorched cars, and craters on the ground as evidence of past resistance. Somewhere on earth, perhaps in Greenland, deep in the Pacific Ocean, or at Cheyenne Mountain in the North American Aerospace Defense Command, detailed information might be preserved, yet those places were beyond Ban Xia's reach.

Though puzzled, the girl continued to perform all tasks as scheduled.

Maybe they had a way of finding out?

—Bai Yang didn't actually know if there was a way. He was simply following Zhao Bowen's instructions to keep pushing the work forward until his return.

If right now, among the seven billion people on earth, there was one who knew the whole plan, it was undoubtedly Zhao Bowen.

Bai Yang didn't know where Old Zhao was now. He hadn't called for a long time, looking for applause. The man had vanished as if evaporated.

Sometimes, Bai Yang's wild thoughts made him wonder if Uncle Zhao had been mistaken for a lunatic and locked up, his mobile and other possessions confiscated, explaining the long period of no contact—imagining such scenes, Zhao Bowen trapped in an intensive quarantine ward, his hair messy, eyes sunken, desperately beating on the metal door and yelling at the nurse to let him out or the world would end, invoking laughter among his fellow patients. An older psychiatric patient next to him would count off his fingers and comfort him, saying don't worry young man, a heavenly warrior will descend in due time.

If it were so, then the world was indeed doomed.

With Bai Yang's limited understanding, he couldn't guess Zhao Bowen's plan, but it seemed Uncle Zhao was playing a long game.

Bai Yang was waiting for Zhao Bowen to make his next move.

If Uncle Zhao's move was successful, they might be able to glimpse the truth behind the apocalypse disaster. However, as Zhao Bowen had yet to make his move, a startling message suddenly came from BG4MSR that made everyone present jump up in shock.

This was a significant turning point, moving Bai Yang and the others a big step closer to the truth.

That big step was thanks to a slipper.

It was just a small step for the slipper, but a giant leap for humanity.