Chapter 271 - 158: Damn! (Part 2)
Dayong reached out and gently placed a hand on the alloy load-bearing support frame on the exterior of the vacuum chamber, silently feeling the vibrations conducted through the metal.
To his senses, this machine, weighing several tons, was no inanimate object.
Countless tiny shockwaves traveled through the metal skeleton. Soon, within this complex web of vibrations, he captured a faint, regular, and hidden low-frequency tremor.
Dayong’s palm followed the vein of this tremor, tracing its way upward inch by inch.
From the main load-bearing column to the horizontal connectors, Dayong’s gaze finally locked onto a black, hard water pipe.
It was the intake pipe that supplied circulating cooling water to the vacuum pump.
One end of the pipe was connected to a high-powered industrial water-cooling pump in the corner of the lab; the other end fed into the vacuum chamber’s heat dissipation layer.
For the sake of tidy wiring, the hard cooling pipe had been fastened tightly to the vacuum chamber’s main load-bearing frame with several thick metal zip ties.
Dayong looked at the water-cooling pump, then at the metal ties.
The water-cooling pump’s motor was running. The micro-vibrations it produced were conducted all the way down the rigid pipe. Because it was tied so tightly, there was no buffer between the pipe and the metal frame. As a result, the vibration was transferred completely to the vacuum chamber’s main structure.
And the operating frequency of the water-cooling pump’s motor was exactly 50 hertz.
Dayong turned his head to look. Not far away, Zhao Peng and Zheng Nan were still in front of the whiteboard, arguing until they were red in the face about how to modify the Hamming window parameters.
He didn’t say a word. He just picked up a wrench and fitted it onto the nut of a metal tie.
CREAK~
With a twist of his wrist, the nut loosened. A gap appeared between the water pipe and the metal frame, which had been pressed tightly together.
Dayong deftly folded a piece of anti-vibration rubber, stuffed it snugly into the gap, and retightened the nut with the wrench.
The rubber was compressed and deformed, lodged between the pipe and the frame. The path of physical conduction was severed.
Dayong placed his hand on the main load-bearing frame again. The annoying, low-frequency pulsed vibration was gone. The frame had returned to silence.
He dusted off his hands and casually tossed the wrench onto the nearby metal workbench.
CLANG.
In front of the whiteboard, Zhao Peng and Zheng Nan stopped writing and looked over.
"Dayong, go easy with the tools. We’re running a real-time data test here."
Zhao Peng remarked casually before turning back to continue writing his formula.
Zheng Nan sighed and walked over to the computer at the workstation.
"Old Zhao, I’ll input this new set of parameters and see how it goes."
He pulled out his chair and sat down, placing his hands on the keyboard. His eyes habitually swept over the real-time curve on the screen.
His hands suddenly froze in mid-air.
Zheng Nan blinked hard, then shot forward, staring intently at the screen.
On the screen, the green curve, which used to have a glitch at regular intervals, had now become completely smooth.
Those annoying 50 Hz sawtooth waves had vanished completely. The data stabilized within a perfectly narrow range, as straight as a line drawn with a ruler.
"Old... Old Zhao."
Zheng Nan’s voice trembled. He didn’t dare speak loudly, as if afraid the vibration from his voice would scare away the perfect curve.
"What is it? Did the parameters work?"
Zhao Peng had his back to him, organizing his scratch paper.
"No... I haven’t even touched the keyboard yet." Zheng Nan pointed at the screen. "Quick, come look."
Hearing the odd tone in Zheng Nan’s voice, Zhao Peng quickly put down what he was holding and hurried over to the computer.
When he saw the data curve on the screen, smooth as silk, he froze too.
"What’s going on?"
Zhao Peng pushed Zheng Nan aside and lunged for the keyboard. He quickly checked the background program and the filter algorithm’s parameter settings. Nothing had changed; it was still the same old code that couldn’t filter out the background noise.
"Old Zheng, what did you just do?"
Zhao Peng turned his head, his face a mask of confusion.
"I didn’t touch a single key."
Zheng Nan held up his hands, equally bewildered.
"I just sat down, and it was already like this. The background noise just vanished into thin air."
The two stared at each other, speechless.
Dayong had just strolled back to his desk, ready to continue reading, when he heard the commotion and glanced at the screen.
"Oh, that line’s looking pretty straight. No more shaking?"
Dayong commented casually.
Zhao Peng looked at him eagerly.
"Dayong, did you do something just now?"
"Didn’t do much."
Standing by his desk with one hand on a thick book, Dayong chuckled and pointed toward the vacuum chamber.
"It’s that water-cooling pipe! When the pump starts up, isn’t the AC motor’s rated frequency 50 hertz? You guys tied it dead tight to the load-bearing frame, so when the pump shudders, how can this big iron frame not shudder right along with it? That’s the most basic mechanical resonance there is!"
Zhao Peng and Zheng Nan followed Dayong’s finger and saw the black rubber pad wedged between the pipe and the frame.
Dayong looked at his two senior colleagues and continued.
"I saw you guys on the whiteboard calculating Fourier transforms for days. Your math is impressive, for sure. But when you were doing your calculations, you must have been treating this big iron frame as a perfectly rigid body, right?"
He walked over to the machine and patted the sturdy alloy frame.
"It’s still metal. It’s going to deform when it conducts vibrations—even if it’s just a few hundredths of a millimeter, the sensors inside will still pick that up. When it’s physically coupled, hard against hard, how can you ever filter out the background noise completely in the computer, no matter how aggressive your algorithm is?"
Dayong walked back, a simple grin on his face.
"I just used a wrench to loosen the tie, stuck in a piece of anti-vibration rubber, and broke the physical conduction chain. Works a lot better than you guys banging on a keyboard, don’t you think?"