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  Due to geographical reasons, every place in the world has its own local time. As long as activities are confined within the same time zone, there is no need to worry about this in daily life. However, wireless telegraphy is a global activity, and if each party uses their own local time for communication, it will cause great confusion. This point was proven early on when wireless telegraphy first emerged.

  Later, in order to solve this problem, the International Radio Consultative Committee stipulated and recommended a unified time standard - Coordinated Universal Time, abbreviated as UTC, also commonly known as International Standard Time.

  It divides the world into 24 time zones, with the Earth's east and west longitudes of 180 degrees (a total of 360 degrees) divided equally among 24 time zones, each occupying 15 degrees. For example, San Francisco in the United States is located in West Eight Zone, eight hours behind Zero Time Zone; while Beijing is located in East Eight Zone, eight hours ahead of Zero Time Zone.

  According to the International Telecommunication Union (ITU), in international radio communication, except as otherwise specified, UTC shall be used and expressed in four digits. Amateur radio communications are conducted worldwide, so UTC should also be used.

  So, the CQWW_DX contest start time is defined as the last weekend of November every year in UTC terms. Considering the identity of amateur radio enthusiasts, the organizers specifically scheduled the time from 00:00 on Saturday to 24:00 on Sunday, a total of 24 hours. To get an award, you must participate in the competition for at least 12 hours.

  Today is Friday, and with a blink of an eye, there's only one week left before the cqww_dx contest starts.

  After school, on the way home, Lin Hong said to Sun Wu: "After finishing your training later, don't rush out, help me with something."

  "What's up?" Sun Wu took out his earbuds while listening to music.

  Lin Hong had no choice but to repeat it again.

  "No problem!" Sun Wu nodded and put the earphones back on again.

  After a while, Sun Wu remembered another thing and pulled out his earphones again, saying:

  "By the way, my brother-in-law said that someone sent a color TV to the shop and he has never repaired one before, so he's not very confident. He asked me to ask if it can be fixed."

  "I'll go back and take a look, it just so happens that I have something to do these two days."

  Color TV is still a relatively rare product in rural areas. In the past, to make black and white TVs look somewhat colorful, many people stuck a colored plastic film on the front of their black and white TVs.

  Sun Wu's elder cousin, Sun Kai, is a clever person. Before opening the repair shop, he knew very little about electronic repairs, but later through self-study, he quickly grasped quite professional knowledge. In the past, if there was a problem, they might have to ask Lin Hong for help, but now such situations are becoming less and less frequent, and it's usually only when encountering some uncommon products that they would call Sun Wu.

  Recently, Sun Wu's income has decreased significantly, and he is already thinking about doing something else to make money.

  Back at the junk collection station, the two of them first stood in a three-body stance, then started practicing their routine with loud whoops and hollers. Sun Wu even asked Grandpa to teach them a two-person practice method, which they repeated back and forth, adding a lot of fun to it.

  Lin Hong remembered his master's "Four Piercings" and "Four Tips" practice method, every move not only made to perfection but also with eyes and facial expressions in sync, shouting when needed, staring when needed, each time fully focused.

  Sun Wu did not agree with this at first and would often mock him, but Lin Hong didn't pay any attention to it. Later, because of this matter, he was severely scolded by his grandfather, which made him more restrained. After a long time, he also felt some of the subtleties of it, and in several fights with others, he applied some of its methods, finding that they were very effective, so he began to learn from Lin Hong's example and started practicing seriously.

  Unlike ordinary exercise, practicing Xingyiquan makes one more spirited the more they practice. Although a little sweat is produced, there is no panting or racing of the heart. Most of the vital energy is sealed within the body and very little is leaked out.

  "What did you want me to help with today?" After finishing his training, Sun Wu didn't rush to leave. He was still thinking about what Lin Hong had said to him earlier. After all, it wasn't often that Lin Hong would take the initiative to ask for his help.

  "I'm going to make an antenna," said Lin Hong, and then he walked towards the room.

  Sun Wu followed behind him and came to the workbench, where Lin Hong pulled out a drawing from the innermost place.

  Sun Wu stretched his neck to take a look, and all he saw was a rough sketch drawn with a few strokes of a pencil. There were several circuit diagrams, and one that seemed to be a cross-sectional view of something, but he couldn't understand any of it.

  "This thing I don't understand, just tell me what to do." Sun Wu said brightly.

  Lin Hong originally didn't expect him to understand either, and he simply explained: "I want to make a long wire antenna..."

  Before he could finish speaking, Sun Wu interrupted and asked: "What is a long-line antenna?"

  Lin Hong thought for a moment and finally said: "To put it simply, it's an antenna with a very long feeder line attached to the top."

  Sun Wu nodded: "Oh... go on."

  "Let's first connect the bamboo poles in the room, tie the wires to the poles, and then climb up to that tree by the window to help me fix the rod. I need to do some adjustments..." Lin Hong pointed to the several bamboo poles in the room, roughly explaining what they were going to do.

  Long wire antennas are very simple, as the name suggests, they just need to be long. Generally speaking, their length is best more than a wavelength or even multiple wavelengths. The CQWW_DX contest has six bands with wavelengths of 160m, 80m, 40m, 20m, 15m and 10m. To get the best effect, the antenna's length should be greater than or equal to 160m.

  But for Lin Hong, this was just an imagination, he didn't have such a long antenna wire. After preparing for a long time, he finally got a metal antenna wire of more than ten meters, which could be used temporarily, but the receiving efficiency was relatively low. Fortunately, the communication mode he planned to participate in was CW, and its impact had been minimized.

  Long wire antennas can be placed parallel to the ground or vertically.

  If placed horizontally, it has a strong directivity like the Yagi antenna, so to get a better effect, the direction must be adjusted continuously. However, due to conditions not allowing it, Lin Hong did not adopt this scheme and decided to use a vertical method, which does not occupy space and can be directly leaned against the trunk of the old locust tree outside the window.

  Adopting the vertical erection method, a good ground grid must also be added under the antenna to improve radiation efficiency. Lin Hong prepared 9 meters of plastic copper wire and cut it into three sections, each 3 meters long.

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