Chapter 237 Project of MIT Radio Association

After lunch, everyone else had something to do. Only Lin Hong followed Wu Fei to the mit radio association. Zhang Xin also had something to do in the afternoon. She said that she was too familiar with the mit radio association.

They can't understand why Lin Hong and Wu Fei are so obsessed with radio.

As Wu Fei walked, he introduced some things about the mit radio association to Lin Hong.

"The call sign of the mit radio association is x, and this is the collective call sign. The association was founded very early, dating back to 1909. It is the oldest university amateur radio station in the United States. At that time, China had not yet started the Xinhai Revolution.

I have to say that since then, China has lagged far behind the West in these aspects.

"The members of the association are mainly mit's students, teachers, and employees."

Wu Fei and Lin Hong came to the X radio room of the Massachusetts Institute of Technology, which is located in Room 358 on the third floor of this building, with a total of two radio operation areas. In addition to the Radio Association, in fact, in mit, there is also an organization that is very closely related to it, called the mit uhf relay association. The call sign is the top floor of the green building, which has a good vision, which is very conducive to weak signal communication in the uv band... "

Wu Fei introduced everything related to radio in mit to Lin Hong in detail.

Because today is the weekend, there are no people in the whole building. Lin Hong didn't meet many people on the road, but when passing through the aisle, through the door cracks of some rooms, you can occasionally see that some people in the room are busy with their own affairs.

Some perform mathematical formulas on the blackboard, while others do experiments in the laboratory.

They came to an area in Room 358 on the third floor.

Lin Hong was completely attracted by the equipment placed in this area. He found that compared with the equipment here, the equipment he had seen before was all slag. This is the artifact-level equipment used in ham!

"It turned out to be a professional radio station of ten-tecorion and ten-tec orionii!" Lin Hong sighed.

Massachusetts Institute of Technology is rich. These two devices are the best equipment in amateur radio equipment, and even reach the professional level. It is a little too luxurious to engage in amateur wireless communication.

"Yes. In fact, these two devices have only been updated for a short time. This is the No. 1 operation area, and the old equipment has been put in the 357 workshop next door. Wu Fei introduced, "Each of these two devices is equipped with a set of kilowatt-level amplifiers, and the two sets of equipment can work at the same time. The antenna includes a set of hf directional antennas and a 160m band full-size dipole antenna.

In addition to these devices, computers are naturally indispensable.

With the development of computers, the connection between radio and computers is getting closer and closer. Computers have the tendency to assist radio communication from the beginning, and even the main equipment. Computers can be competent for most of the functions that can only be completed by the special hardware of radio stations before.

It's too luxurious, too luxurious!

After listening to Wu Fei's introduction, Lin Hong sighed repeatedly. At the same time, he also felt a little itch in his heart. Seeing such a luxurious equipment, he was really moved, and he had not touched the radio station for a long time.

"Can I try it?" Lin Hong asked with some embarrassment, "I'm ashamed to say that it's the first time I've seen such a high-end equipment."

"Of course." Wu Fei said, helping to start the power of the radio station.

Lin Hong took on the headphones and began to tune the frequency to monitor the signals on the amateur frequency band.

Although he has never used such luxurious and advanced equipment, the principle of radio has not changed. FM and amplitude modulation are always indispensable. Lin Hong can also see how to use it from the words on the knob.

Listening to the familiar rustle in the headphones, Lin Hong's face showed a heartfelt smile.

I haven't seen this feeling for a long time.

Lin Hong entered the novice channel, established a connection with several novices, and after pointing out several basic ham knowledge of them, he went offline.

"I haven't used the radio for a long time, and I'm a little rusty." Lin Hong smiled and said, "I'm ashamed to say that this kind of high-end goods is used for the first time."

"I think you use it very well. Even professionally trained check-in staff are not as proficient as you. Is it really your first time using it? Wu Fei had just been observing Lin Hong's operation of the radio station, and found that his operation was straightforward, the frequency modulation was accurate, and very old-fashioned. In my heart, I really deserve to be the champion of cqww.

"Yes, the radio station I used before was still an amateur radio station left by Riben Ham in our place. Although it took so long, I repaired it and it was still quite easy to use. I used that radio station to participate in the competition."

"Acow!" Wu Fei gave Lin Hong a thumbs up. He had to admire that the other party won the championship with an antique-level radio station. He had no words to describe his mood.

Workspace 2 has a yaesu ft-2000 device and a power amplifier.

Next to the radio room, Room 357, is a small museum of x, which collects some ancient components and radio equipment, and all the old equipment that was replaced before has also been moved here.

Although it is old, it can still be used, but it is a pity that these devices are piled up in the corner with dust.

When Lin Hong saw these devices, he was a little drooling. There is even an impulse to buy them all back.

But he gave up later. The equipment took up too much space. If he moved all of them back, his room would be full.

After all, he still has a lot of inconvenience in other people's homes.

In this workshop, Lin Hong also saw some strange equipment.

These devices seem to be a complete set, installed on a shelf that can be pushed, with computers and several devices that Lin Hong has never seen before.

There are a few manuscript papers on this shelf, which attracted Lin Hong's attention.

He took a closer look and found that some data were densely recorded on these manuscripts.

"What kind of device is this?" Lin Hong asked curiously.

Wu Fei is helping to sort out some scattered documents. He looked back and replied, "This is the portable ground equipment of our school's gns monitoring station."

After that, he asked again, "gnss, do you know?"

Lin Hong shook his head: "I haven't heard of it."

"This is the abbreviation of global navigation satellite system, which is translated into Chinese as global navigation satellite system. At present, there are two main parts, one is the American gps system, and the other is the glonass developed by the Soviet Union.

Lin Hong nodded slightly. This thing sounds really high-end and involves satellite communication.

"Sesers of our association, under the leadership of a professor, are working on a project to use this set of equipment to try to crack the channel-coded chip sequence of gps and glonass to see if there is such a possibility. Once the cracking is successful, the prototype can be developed according to the coding rules to obtain and track the signals of Soviet navigation satellites.

Wu Fei is also a member of this project team, so he knows more about this matter.

Lin Hong was fascinated by it.

He asked, "What antenna do you use to obtain satellite signals?"

He has studied the mobile phone technical manual. Of course, he knows that the signal emitted from the satellite has a great attenuation after a long trek. The power of the antenna on the earth is basically only 10 minus 16th watt level. If you want to receive these signals accurately, the general antenna can't complete this. Tasks.

Wu Fei handed Lin Hong a look of admiration, because the question asked by the other party directly asked the key. This is "a person who knows whether there is any or not as soon as the artist takes action."

"The antenna we use is the butterfly antenna of the monitoring station, with a radius of 1.8 meters, which can amplify the received signal more than 300 times."

It's another artifact!

This antenna is so powerful.

Lin Hong is sure that this antenna is definitely not the exclusive equipment of their association, but is used for scientific research.

It's great to do research in mit. You can even use this level of equipment!

However, Lin Hong still felt strange that even if the satellite signal was amplified more than 300 times, the signal was still too weak.

However, Wu Fei is a little unclear about this point. He just told Lin Hong that this is related to the coding mode of satellite communication. Through special coding, the weak signal can be amplified from the algorithm. He doesn't know how to do it.

In addition, the core of the ground equipment, that is, this set of equipment on the shelf in the workshop, is Agilent's 89600 vector signal analysis system. With its dedicated vxi bus test equipment, it can make a very in-depth analysis of RF signals.

It's really insightful.

Lin Hong found that compared with them, the things he had done on the radio before were simply worthless.

It's really higher than a mountain. Without comparison, you will never know how big the world is.

Lin Hong really felt that he had too little knowledge and had too much to learn.

He secretly decided that during the upcoming summer vacation, he would stay at the Massachusetts Institute of Technology, either reading in the library, or hanging out with the students of Mit to learn something. Anyway, he has long heard that the management of mit is very free, and it is allowed to occasionally attend the professor's class.

Lin Hong saw that there was still some manuscript paper on the shelf, which was hung next to the shelf in folders. Lin Hong wanted to pick it up and have a look, but he was worried that it would be a little abrupt.

At this time, Wu Fei suddenly said, "Take a look here now. I'll go to the toilet."

"Okay."

When Wu Fei walked out of the room, Lin Hong immediately picked up the manuscript paper on the shelf and looked at it.

The above are all the observed and recorded data. Lin Hong can't understand it at all, but he subconsciously uses his strong memory to remember these data in his brain.

The manuscript paper is turning quickly, and Lin Hong's brain is also running rapidly at this moment, almost reaching the realm of ten lines at a glance.