Once We Lived in Nanjing

After ten o'clock at night, Bai Yang connected to BG4MSR.

Three greasy old men crowded over to eavesdrop by the corner, winking and smirking with an expression that said, "Kid, you've got skills."

Bai Yang was greatly annoyed and kicked these three old rascals out.

"This is Yangyang's signal, strange...why is it so weak?" Wang Ning pointed to the peak on the spectrum analyzer's monitor, looked up at the ceiling, and asked, "We are right under the antenna, right? Bai, what antenna are you using now?"

"DP antenna," Bai Zhen said, "the same one as before."

Wang Ning clicked his tongue in wonder, "Admirable, Bai, I always respect how you manage to set up such a big antenna in the residential area without getting complained about. Didn't any seniors come knocking on your door saying it emits radiation that could cause cancer?"

"Yeah, they went to the property management, and they came to me," Bai Zhen said.

"What did you say?"

"I said I have all the necessary licenses, it is legally installed. If they dare, tell them to go find Wang Ning at the Radio Management Committee. His address is 37 Longpan Middle Road, Xuanwu District. Just look for the one with the least hair when you enter."

"F**k," said Wang Ning.

The peaks on the spectrum analyzer's monitor rose and fell, rising when Bai Yang spoke and falling when Bai Yang listened. The Icom725 operates in half-duplex mode, which means it can't transmit and receive at the same time. To laypeople, it feels more like using a walkie-talkie than a cell phone. When Bai presses the transmit button on the mic, he can't hear what the other person is saying. He has to release the transmit button to receive the signal.

That's why during radio communication, people often add "OVER" or "finished" at the end of their sentences, to let the other side know they've finished talking and it's their turn to speak.

Wang Ning's approach was simple. They listened to Bai Yang's voice in the room while watching the waveform on the spectrum analyzer's monitor.

"...Yes, we are conducting an experiment. Do you know what a spectrum analyzer is? It's a device that can receive and analyze radio waves, and it's right here in my living room," Bai Yang's voice came from the room, "The three of them are checking the signal, hoping to find the cause of all this. But it's still preliminary work, OVER."

As Bai Yang's voice trailed off, the peaks on the spectrum analyzer trembled and fluctuated. The SSB mode uses a narrow bandwidth, so the peaks looked like the steep and narrow path of a mortar shell.

Bai Zhen, Wang Ning, and Zhao Bowen all heard Bai Yang's "OVER."

Good, now Bai Yang had finished talking, it was BG4MSR's turn to speak. If the spectrum analyzer could pick up the signal from that girl, a peak would rise on the 14 MHz frequency...

The three men widened their eyes.

"Where's the peak?" Zhao Bowen asked.

Only sawtooth-like noise lines appeared on the spectrum analyzer's monitor.

No peak emerged.

"Yangyang—!" Wang Ning shouted, "Is she speaking?"

After a few seconds of silence in the room, Bai Yang replied, "Yes!"

"Why is there no signal if she's speaking? Now that's really spooky," Bai Zhen muttered, even with his extensive experience as a HAM, he had never encountered such a situation.

"Yangyang! Give me an RS signal report!" Wang Ning shouted again.

"59+!" Bai Yang answered.

"Impossible, a 59+ signal and the spectrum analyzer doesn't even pick it up?" Zhao Bowen frowned.

"Don't panic, let me try it," Wang Ning stood up and entered Bai Yang's room, "Yangyang—! Let me have a look!"

There's a saying, a thousand toads will give a thousand 59+. And dishonest toads like Bai would claim 59+ on any signal, there's no guarantee Bai didn't inherit that habit from his dad.

A few minutes later, Wang Ning returned, and under his shiny bald forehead, Zhao Bowen and Bai Zhen saw a face that looked shockingly overwhelmed.

That would have to be quite a shock to shake Wang Ning's old face into something historic.

"Close your mouth, baldy with a crack." Bai Zhen said, "What's happening?"

"Old Zhao, if you win the Nobel Prize in Physics, can you give me a mention?" Wang Ning asked.

"Sure, no problem. I'll definitely dedicate it to you when I get the Nobel," Zhao Bowen nodded, "Now tell me, what's happening?"

"The signal is 59+, crystal clear, no issues," Wang Ning took a seat on the chair, "I can't explain this. Bai, you didn't pull any tricks, did you? Did you encrypt the signal?"

"I don't have that kind of skill," Bai Zhen said, "and Xiao Bai doesn't have it either."

An eerie silence fell in the living room, and Mama Bai emerged from her room, curious at the sight of the three men sitting quietly on the sofa and chairs:

"What's going on here?"

"Could Yangyang's story actually be true?" Zhao Bowen whispered, "Is there really a signal that travels through time? Does BG4MSR really live twenty years from now?"

"You're the professor, you tell us," Bai Zhen said, "Were all those ten extra years of schooling for nothing?"

"Got the degree anyway," Zhao Bowen said.

"Let's not rush to conclusions, let's think of something else."

As Wang Ning spoke, he took out his phone from his pocket and began to dial:

"Hello! Xiao Zhu? Yeah, yeah, it's me. Where are you now? Have you gone home yet... Ah, that's perfect! Perfect! Xiao Zhu, could you do me another favor? You got any time? It's just going back to the office to grab another spectrum analyzer for me, the HP one, yeah, that white one... Really sorry to bother you again, I'll treat you to a meal tomorrow."

Half an hour later.

A panting young man appeared at the door again, holding a white, old-style HP spectrum analyzer.

Old Wang insisted on offering him a drink of water again.

Xiao Zhu waved his hand, declining, and disappeared in a flash.

"What kind of leader are you? The young fellow runs errands for you in the middle of the night and you offer him a drink of water?" Bai Zhen said indignantly.

"Drink whose water?" Zhao Bowen asked.

"Can you two stop giving me grief or will you die?" Wang Ning put the second spectrum analyzer on the table and connected it to the power, "Come, check this one!"

The first spectrum analyzer couldn't pick up the signal from BG4MSR, it could be the device's problem.

So, they tried with another spectrum analyzer.

The three men stared at the spectrum analyzer's display. The dismal green light from the old HP's oscilloscope—it was hard to tell if it was as old as the three geezers present—but old as it might be, it stood firm—Wang Ning's words were, "It's as steadfast as me, serving the country for fifty years in good health."

But the veteran that usually stood unyielding had met its match; the second spectrum analyzer could still only detect Bai Yang's signal and was unable to display BG4MSR's. Eventually, Wang Ning even moved the analyzer into Bai Yang's room, just a meter away from the Icom725 radio, both devices started working in sync—but even then, the BG4MSR signal still ignored the analyzer, with only Bai Yang's battered radio able to receive it.

It was inconceivable.

"I knew it," Bai Zhen slapped his thigh, "Old Wang said this thing's condition is just like his own. Isn't that a disaster? It's got senile dementia."

The three people present, Bai Zhen, Wang Ning, Zhao Bowen, were all experienced amateur radio experts, but none could explain the phenomenon.

Why would BG4MSR's signal be selectively received by Bai Yang's Icom725?

Has the radio wave become sentient?