Siheyuan (traditional courtyard house): Starting with the Korean War, returning home to take charge

When the General Staff called, He Yuzhu was looking at the border map. The red circles stretched from northeast to northwest, then from northwest to southwest, like a rope bent by the wind. He stared at those circles for a long time, his fingers tapping unconsciously on the table. The phone rang, and he answered it. The voice on the other end was very low, as if afraid someone nearby would hear.

"Chief He, there's another problem with the border troops. The phone lines are intermittent, sometimes taking forever to connect. They freeze and break in winter, and lightning strikes in summer; the soldiers can't keep up with the repairs. It almost caused a disaster the other day." There was a pause on the other end, the voice lower. "The higher-ups are asking if there's any other solution?"

He Yuzhu didn't reply immediately. He glanced at the map on the table, at the long red circle marking the border, stretching from Heilongjiang to Xinjiang, and from Xinjiang to Tibet. He had been to those places; in winter, water poured on them would freeze instantly, and in summer, swarms of mosquitoes would swarm. The telephone lines stretched along the mountain ridges, snapping easily in the wind and collapsing under the weight of snow. He held the receiver, pausing for a few seconds before speaking.

Microwave communication. No wires required, transmits through the air. Unaffected by freezing or lightning.

There was a moment of silence on the other end. "I've heard of it, but I've never done it before. Is it feasible?"

"Yes," He Yuzhu said decisively, pressing down on the table with one hand.

He put down the phone and took the key to the archives from the drawer. The key was icy cold and felt uncomfortable in his hand. Two lights in the corridor were broken, leaving gaps in the darkness every few steps. His leather shoes echoed on the terrazzo floor, each step sounding like someone following him. He stopped at the archives door, took out the key, inserted it into the lock, and turned it twice before it opened. The iron door creaked open with a dry sound, and a blast of cold air rushed out, colder than the corridor itself, like an icebox.

He rubbed his hands together, walked to the innermost row of cabinets, and opened the door labeled "Communications - Microwave Relay." The metal door was cold to the touch, so he adjusted the angle and used his sleeve to push it open. Inside, a stack of documents was wrapped in kraft paper, with the words "Microwave Relay Communication Technology" written on it in pen, each stroke carefully made, though the ink had faded considerably. He took them out, untied the rope, and turned to the first page. The flowchart was densely packed with lines like a spiderweb, the arrows zigzagging, and the small annotations were barely legible, requiring him to point to them. Antennas, feeders, transceivers, multiplexing equipment—each component was interconnected, interspersed with a few lines of handwritten notes, the handwriting messy, as if hastily written.

He looked at it for a long time, then closed it and wrapped it up again.

The next morning, He Yuzhu went to the Ministry of Posts and Telecommunications. The office building was located on Chang'an Avenue; several pieces of plaster had peeled off the exterior walls, revealing the red bricks underneath, and the paint on the window frames was peeling off. Two sentries stood at the door, wrapped tightly in cotton overcoats, their noses red from the cold. He showed his identification, the sentries glanced at it, saluted, and let him in. People were coming and going in the corridor; some were carrying documents, others were carrying enamel mugs, their steps hurried. He went up to the third floor, found the deputy minister's office, the door was open, and there was a strong, pungent smell of smoke inside.

The deputy minister, surnamed Liu, was in his fifties, thin, and wore black-rimmed glasses with a layer of dust on the lenses. He was talking on the phone, gesturing towards a chair when he saw He Yuzhu, indicating that he should sit down. He Yuzhu didn't sit down but stood in the doorway to wait. Minister Liu said a few more words, put down the receiver, and stood up.

"Where did you grow, and what wind blew you here?"

He Yuzhu placed the document on the table. "Microwave communications. Border troops urgently need it. Wired telephones disconnect in winter and summer. Microwaves are safe from freezing and lightning."

Minister Liu picked up the documents and turned to the first page. He read slowly, his finger tracing the flowchart, stopping when he reached the equipment list page.

"We have the equipment. Several factories in Beijing and Shanghai can make it. But the conditions in the west and border areas are poor, and it's difficult to build a station. In winter, it's minus forty degrees Celsius, and the equipment freezes and stops working. In summer, it's forty or fifty degrees Celsius in the Gobi Desert, and the equipment malfunctions when it gets too hot." He pushed up his reading glasses and looked at He Yuzhu. "Director He, it's not that I don't want to help. Two years ago, a station was built in Qinghai, and the equipment cracked from freezing during transport. The manufacturer sent people to repair it, but the truck broke down halfway there and was frozen for a day and a night."

He Yuzhu didn't reply. He recalled that year at Changjin Lake, when he lay prone in the snow waiting for the bugle call to charge, the bolt of his rifle wouldn't pull back, and his hands were frozen to the butt of the rifle. Minus forty degrees Celsius was no joke.

"I'll figure out the equipment. If it's cold- and heat-resistant, we'll have the factory modify it. If they can't, we'll buy it from abroad." He looked at Minister Liu. "You guys first select the site and prepare the tower foundations. Once the equipment arrives, install it immediately."

Minister Liu stared at him for a few seconds, then closed the document. "Let's start with a pilot program. Build one station each in Xinjiang and Heilongjiang, and see how it goes."

He Yuzhu stood up and extended his hand. Minister Liu grasped it and shook it. "Director He, let me be clear from the start, if it cracks again from the cold, don't blame me."

"It won't crack when frozen."

He Yuzhu turned and left. The smell of smoke still lingered on his clothes; he tried to brush it off, but it wouldn't come off.

The first station in Xinjiang was built at the foot of the Tianshan Mountains. He Yuzhu didn't go, but Yang Xiaobing did. Half a month later, Yang Xiaobing's voice was hoarse on the phone, as if he had sand in his mouth.

"Commander, the equipment is frozen. It's not responding when powered on. The technician said the power module isn't working at low temperatures."

He Yuzhu gripped the microphone, his fingers tightening. "Was an insulation layer added?"

"We added more. It's not thick enough. The equipment can't withstand the -38 degree Celsius temperature at night."

He Yuzhu thought for a moment, and the image of the equipment cracking from the cold flashed before his eyes. That year at Changjin Lake, his comrade's rifle bolt froze and couldn't be pulled back. When the enemy charged, he could only use his bayonet.

"Have the factory modify the circuitry and add heaters. Keep them warm with a hairdryer to prevent the equipment from freezing. I'll have someone deliver the parts tonight."

He answered with a "yes" and hung up.

Three days later, the phone rang again. Yang Xiaobing's voice was much clearer than before.

"Commander, it's been replaced. The self-test has passed, and the signal is working. The border regiment commander tried it out and made a call to Beijing; the sound was perfectly clear. He said it's even clearer than a landline phone."

He Yuzhu held the microphone, remaining silent. Outside the window, the sky was overcast, threatening snow. Several more large-character posters on the courtyard wall had been blown away by the wind, revealing the dusty, gray cement underneath. He looked at them for a while, then drew the curtains.

"What about Heilongjiang?"

"It's working now. It's over minus thirty degrees Celsius in Mohe, but the equipment is fine. The factory modified the circuitry and added insulation, so it won't freeze."

He Yuzhu didn't speak. He stood up, walked to the wall, and looked at the map. Next to the two red circles, Heilongjiang and Xinjiang, he drew a small checkmark with a red pen.

The station in Tibet took three months to build. He Yuzhu didn't go; Ma Yuejin went instead. When he returned, his face was sunburned and peeling, his lips were cracked in several places, and there were dark circles under his eyes. He threw a stack of photos on the table and slumped into a chair.

"Director, at an altitude of 4,700 meters, the air is thin, and it took several days to stabilize the equipment. Workers carried the equipment up and down the snow, and yak oxen carried the iron tower components along the cliff edge. There was a soldier, in his early twenties, from Gansu, who had been stationed on the border for three years and had only been home once. Last month, his mother fell ill, and the letter took a month and a half to arrive. When he finally received it, it said she was 'out of danger.' He was worried and wanted to call, but the nearest phone was at the regimental headquarters, and the heavy snow blocked the mountain pass."

Ma Yuejin picked up the enamel mug and took a big gulp of water, which dripped down his chin. He wiped it with the back of his hand.

"The day the microwave station was connected, he picked up the receiver and dialed the number several times. It rang three times before he answered. It was his father's voice. He said, 'Dad, it's me,' but before the other end could respond, tears started streaming down his face. He bit his lip, trying not to cry out loud, but tears fell drop by drop onto the receiver."

He Yuzhu picked up a photograph. In the photograph, a soldier wearing a military overcoat and a leather hat stood under an iron tower, holding a microphone in his hand. Tears streamed down his cheeks, leaving a white mark on his cheek—his face was covered in ash, but that mark was clean.

He Yuzhu put the photo down, took the list from the drawer, and turned to the "Communications" page. After the words "Microwave Relay," he added a line: "Xinjiang, Heilongjiang, and Tibet stations are now operational." He finished writing, put the list back, and locked the drawer.

Not long after the station in Tibet opened, Ma Yuejin called again from Tibet.

"Dean, a batch of transistors in the transceivers burned out, and the factory doesn't have enough stock."

He Yuzhu frowned. "What's going on?"

"The quality of this batch of tubes is substandard. The manufacturer says the production line is outdated, production capacity is limited, and they are still using old processes. Our microwave station uses a lot of tubes, and they can't supply enough."

He Yuzhu was silent for a moment. He thought of that lithography machine production line, and of Galaxy-1, Galaxy-2, and Galaxy-3. Those computers could be built, and integrated circuits could be built too. But that line had low output; it wasn't even enough to supply computers.

"What about the lithography line?"

Ma Yuejin said, "The output is too low; it's not even enough to supply computers. They can't produce the tubes for microwave stations that quickly."

He Yuzhu put down the phone and stood by the window. The microwave network was built, but the components couldn't keep up. Antennas, feeders, transceivers, multiplexing equipment—every single one required transistors, capacitors, resistors, and integrated circuits. Domestic integrated circuit production lines were just starting out, with low output and unstable quality. The factories had outdated equipment, and the workers were unskilled, resulting in inconsistent quality.

He took the list out of the drawer again, turned to the "Electronics" page, and wrote a line in the blank space: Integrated circuit production line, needs to be expanded.