"Little brother!" Zhang Heng had just walked to the door of the store, and the young man chased after him, his face was a little shy, and he twisted, "Can you please discuss it together." ”

"Dude, did you really invite me to participate?" Zhang Heng pointed to himself.

"Yes, listening to what you said just now, looking at the equipment you bought, I think you should also be a fellow believer, since this is the case, it is better to come together. The young man said sincerely.

"Okay!" Zhang Heng responded quickly, instructed Chen Zhenning to wait, and strode back to the counter, which surprised both the young man and Zhang Zhefeng.

"You guys, this is the antenna circuit diagram. Zhang Heng pointed to the circuit diagram and asked directly.

"Yes, this is the circuit diagram of the fishbone antenna, which we copied from an American magazine. Zhang Zhefeng nodded and introduced, "This is Lin Wencan, we are going to make a fishbone antenna according to this drawing, but after setting up a board to test, the amplification gain is only 4.3dB, so the ratings are not very optimistic." ”

Fishbone antenna is a popular term, because the antenna appearance is arranged like a fish bone, in fact, this antenna has a special name: VHF/UHF TV signal receiver, VHF refers to VHF, UHF refers to UHF.

At a certain historical stage, in the southern region near Hong Kong and Macao, there used to be such high-raised fishbone antennas everywhere, and the relevant departments forcibly dismantled them, and the people below continued to install them, and the intensity of the plot was like the ups and downs of guerrilla warfare, and the turmoil caused by this even spread to the sea side of the capital.

In 1972, the external antenna, especially the fishbone antenna, was still a high-end product that most people did not have, which is also the reason why the Xiangjiang antenna was able to become popular.

"I think we should increase the LC value of the front-end circuit. Lin Wencan stared at Zhang Heng, who was deep in thought, waiting for his insight.

"Why don't you use an integrated amplifier with a three-terminal regulated power supply to build a circuit?" asked Zhang Henghui.

"Little brother, those two components are so expensive, where is this kind of UHF transistor cheap. Zhang Zhefeng smiled bitterly.

This is also the case that the most popular amplifier on the market today is Fairchild's uA709, plus a three-terminal regulated power supply, which costs at least ten times as much as this design solution.

Zhang Heng nodded, took Lin Wencan's pen, added a 3V power supply to the drawing, brushed a few strokes to connect the corresponding capacitor resistor, threw down the pen, and said lightly: "Do you think this is okay?"

The two glanced at the circuit diagram, looked up at him in shock, Zhang Zhefeng immediately leaned over and calculated, and muttered:

"The power supply is divided into two groups of supply, the current at the junction of the triode B, E junction and the junction B and C does not affect each other, the input and output terminals have a good isolation effect, the working frequency of the circuit can be increased, and the sufficient bandwidth is ensured, and the gain can be increased to ...... as far as a triode is concerned."

"The theoretical value is 2 times, but in reality it should be less than that. Zhang Heng took over, "If you want a larger gain, you can add another triode into it." ”

"Great!" Zhang Zhefeng threw down the pen, turned over the wooden board and walked out of the counter, holding Zhang Heng's hand, his eyes were full of little stars, "Little brother, we still have a few questions......

A lot of the knowledge of these analog circuits has been returned to the school, and this is still a ghost to recall, and if you talk about it more, it will be exposed, Zhang Heng looked at Chen Zhenning who was waiting at the door as a hindrance.

Zhang Zhefeng is a shrewd person, and immediately smiled: "There will be opportunities in the future, today the little brother helped us solve a big problem, why don't I invite you to go to the back street to drink a cup of milk tea, and everyone get to know each other?"

Zhang Heng was also very interested in these two people, and deliberately thought about it before agreeing, Zhang Zhefeng hurriedly called his father down from the warehouse upstairs to look at the store, and took the three of them out of the back door of the store to Ruzhou Street, and entered a stockings milk tea shop.

Originating from Hong Kong, Silk Stockings Milk Tea was first created in the 50s by Mr. Dong Lin Muhe, a long-established brand in Central, Lan Fong Yuen, because the white cloth net pocket that filters the black tea is dyed into the color of stockings, hence the name.

When Zhang Heng heard this name for the first time in his previous life, he didn't feel fragrant, but felt disgusted, and only after a good check did he feel at ease.

A cup of steaming stockings milk tea was placed in front of everyone, and before they started drinking, Zhang Zhefeng took the initiative to introduce the two of them in detail.

He and Lin Wencan are both born in 49, is the same class of Xiangjiang World Electrical Engineering School, after graduating 3 years ago, he took care of the family heirloom shop for his father, and Lin Wencan went to an electronics factory as an engineer.

"Do you want to organize production when you research fishbone antennas?" After listening to their brief resumes, Zhang Heng did not rush to introduce himself, but asked about the circuit diagram just now.

"For the time being, there is no such idea, and the investment is too big and the risk is very high. Lin Wencan said, he looked very shrewd, and he didn't talk much, and he really said the key point as soon as he opened his mouth.

"Maybe you can consider selling this technology to Xiangjiang Antenna, by the way, have you heard of this company?" Xiangjiang Antenna has risen to more than 55 yuan, thinking of the arrogant face of the pair of living treasure father and son, the corners of Zhang Heng's mouth turned up slightly.

Zhang Zhefeng said slowly, it turned out that they had already brought the first version of the circuit board to find Chen Pufen, but they didn't expect that they didn't even give them five minutes, and after listening to an opening remark, they politely invited them out of the office, making them so angry that one Buddha was smoking, and the second Buddha was born.

"The newspaper is right, it's a wire company!" Lin Wencan pouted.

Zhang Heng smiled, "Industrial and Commercial Daily" reprinted his definition of Xiangjiang antenna, it seems that some people still remember.

"Don't be angry, anyway, we sent the information to several newspapers including the "Industrial and Commercial Daily", this kind of scam company, there are not a few days to live. Zhang Zhefeng said with a big grin.

"Zhefeng, be cautious!" Lin Wencan exclaimed urgently, Zhang Zhefeng knew that he was speechless, and hurriedly observed Zhang Heng's reaction.

Zhang Heng lowered his head and drank milk tea, pretending not to know, and sighed in his heart, he didn't expect that the Xiangjiang antenna was originally exposed by them, he had just beaten Chen Pufen, and he had earned the first pot of gold from the Xiangjiang antenna, and he met them when he came to Yaliao Street for the first time today, this world is really wonderful.

"By the way, I haven't introduced myself yet, this is my business card. Zhang Heng handed over two newly printed business cards.

"Daheng Printing Paper Boss Zhang Heng!" The two of them looked surprised, and unconsciously spoke with some compliments, "I didn't expect you to look young, but you are already the boss of a company, disrespectful!"

It seems that they didn't think of who I was, maybe it was also dark under the light, Zhang Heng said secretly in his heart, and said humbly: "It's just a small printing shop, I just took over from a friend, and the business hasn't started yet." ”

He looked at the two of them sincerely, "But I hit the two of them at first sight, I don't know if I am interested in coming to work in my company?"

PS: Thank you old friends [Baby Cat Bear, Silent, Cold Gray, Young Master Bai] 100 rewards each!