Chapter 9

After a while, the radio returned to normal and played the music on the tape.

"Sweet honey, your smile is very sweet, as if the flowers are blooming in the spring breeze..."

An unknown singer has a nice voice.

"That's the problem. It's just like this when you start up at the beginning. You'll be fine later. I don't know why... "

The little uncle said, and his heart suddenly became uneasy.

He once went to several businesses to repair this thing.

But these businesses simply dare not take over the work, because once it is repaired, they will lose money.

These ancient electronic products are very delicate. Maybe if you touch them a few times, a route inside will break.

Moreover, various parts of the radio have long been discontinued.

Even if there are factories, they can't sell at any price. Antiques and antiques want the word "ancient". If modern electronic components are installed on ancient instruments, what's the difference between sticking a dog skin plaster?

Anyway, it can be played normally, and my little uncle can only get together to use it.

Zhang Yuan eagerly went to the radio: "let me fix it!"

"Well... Alas."

"Try it."

A tone of apparent distrust.

The little uncle kept complaining and felt that he had gone too far.

Although my nephew is awesome. He is a "ship management" major and can even repair a ship, there is a difference between repairing a ship and repairing a radio!

The most important thing is that it's impossible for your nephew to lose money if it's repaired!

Seeing that Zhang Yuan's hands had touched the radio, his heart was pulled up!

But because of his face, he couldn't say anything more. He just looked back at his daughter.

Ye Qingqing shows no weakness. She also stares back at her father and smiles in her heart. In her opinion, such old directors have long been discontinued, and even the design drawings have long been lost. Who else can repair them?

Especially... The difficulty of dealing with small problems is far greater than that of big problems.

When you bring down your cousin, the "child of others", you can always breathe a sigh, and it seems to prove that "reading is useless" and you can read less books in the future

At this time, Zhang Yuan has unscrewed the housing screws of the radio to expose the electronic structure inside: switch, power supply, variable capacitor, potentiometer, magnetic rod and so on. It is not too complex.

It is these uncomplicated things that have withstood the test of time and remain until now.

The more complex and delicate things are, the easier they are to be damaged. Warwick and apple smartphones in the 21st century have few left, and each one can be sold at a sky high price.

Zhang Yuan has never repaired this kind of antique, which is a new challenge.

In the past, he might have avoided it, but now he has a wonderful desire to explore.

Took a deep breath and the brain began to run fast.

He tried to infer the working mode of the radio from what he had learned in the past.

Any electronic instrument plays with electrons and magnetic fields, which are basically the same. The working principle of radio is nothing more than converting audio signals through various circuit structures.

"This radio just used tape broadcasting, so the antenna, variable capacitor and detection circuit are basically useless. The noise at the beginning is unlikely to be an error in these parts... "

"Could it be a tape problem?"

Zhang Yuan took out the tape, reset it manually and stuffed it back.

"Sweet honey, you smile very sweet..."

This time, play from the beginning, there is no noise in the middle.

Zhang Yuan changed another tape and pressed the play button.

"I can't stop loving you..."

There is still no noise.

"So it shouldn't be the tape."

Seeing that he was trying again and again, the little uncle became more and more anxious and hurriedly said, "there will be a loud noise only when he starts up, and there will be no noise behind him. I can't... forget it... "

His heart was always clenched, just hoping that his nephew would retreat in the face of difficulties.

Don't fix it.

Master, don't fix it!

"Is this only the beginning?" After waiting for some time, Zhang Yuan took the radio under the air conditioner and blew it for ten minutes.

Plug in the power again. Sure enough, the cooled radio began to roar again.

"Buzzing - buzzing!"

The harsh voice made the liver ache.

It took a while for it to stop.

Zhang yuanruo thought.

The whole process of troubleshooting errors is a bit similar to debugging in computer programming. Now that we have determined how the bug occurs, we only need to find the cause and solve it.

Zhang Yuan paced back and forth in the room, thinking quickly about the suspicious points.

poor contact?

No, poor contact will not yell at the beginning, but will only stop working intermittently.

"It's not a phenomenon of electric current."

After thinking about it, it may be a preheating problem.

This old radio uses vacuum tube technology.

There are two main devices in this nearly vacuum closed chamber: one is called the heating electrode, which is located in the center of the electron tube and will emit light during operation; The other is composed of cathode, metal grid and metal plate.

"If the vacuum tube warms up irregularly in the circuit, it will lead to the voltage disorder of the whole circuit. This part of the disordered voltage was mistakenly transmitted to the rear amplification circuit, so when there was no electrical signal, the recorder shouted. "

"Finally, when the RF line is all hot, the vacuum tube voltage has been adjusted, everything returns to normal, and the recorder works normally."

Zhang Yuan clapped his hands. That should be the reason!

The little uncle saw Zhang Yuan pacing back and forth, just eating fruit. He felt that he was in a bad mood: where would a normal repairman walk around.

Ye Qingqing just chuckles.

Zhang Yuan lowered his head and narrowed his eyes. He began to disassemble the vacuum tubes one by one.

He's really starting to tear it down!

I

The little uncle was almost ready to cry and trembled: "Zhang Yuan, I really can't. I'd better go to a professional antique repair shop! I know a great master... But the price is a little high. "

Zhang Yuan turned a deaf ear and devoted himself to his work. He really didn't hear what my little uncle was saying.

He changed the arrangement of vacuum tubes again, then screwed in screws and waited for the radio to cool down.

My sister-in-law blushed and couldn't help muttering in his heart: won't it be broken? Is there an extra part?

Even my sister-in-law couldn't see it anymore: "look at your nervousness. It's just a radio. Why?"

"What do you know? Even if it's just a radio, do you know its history? It's very... "

Zhang Yuan didn't answer, just pressed the play button.

Click——

The radio is like a docile sheep. It warms up obediently and there is no noise anymore.

"Sweet honey, you smile sweetly..."

The soft song echoed in the air.