Lin Yuan's words seem to be an understatement, and there is nothing special about it to the layman, but to the insider, this sentence is almost provocative! Military equipment has always been preferable to light and small, and the lighter the weight and small size, the more space will be saved, and there will be a great advantage in the layout of the entire system.

Lin Yuan said that this stereo rangefinder is very large, which is equivalent to saying: "You Germans' equipment is not good, it is far behind!" ”

Of course, Wilhelm II heard Lin Yuan's voice, he didn't say anything, but said with a smile: "Mr. Lin Yuan's knowledge is good, you also know this equipment, I'll show you other equipment, I don't know if you know it." ”

Lin Yuan smiled: "You lead the way in front." Wilhelm II then made a gesture of please, took Lin Yuan to the front, walked past a booth, and saw that the platform was full of colorful handicrafts, Lin Yuan stopped on the side and asked, "What are these?" ”

Wilhelm II smiled: "These are our German folk crafts, you may think that these things should not appear at the technical fair, but you don't know, these crafts are works of art, in my opinion, art and technology are the essence of our German culture......"

Lin Yuan had learned Wilhelm II's "excellent" appreciation of art at the banquet, and when his voice paused, he hurriedly said: "Since this is the case, let's all take a look, I wonder if you can buy some back?" ”

Wilhelm II smiled and said, "If you like it, I can give you a batch." ”

Lin Yuan thanked him again and again, and then beckoned everyone to come forward to watch. Lin Yuan took advantage of the fact that everyone separated him from Wilhelm II, and quietly said to Shen Wanqing: "Did you take a picture of that stereo rangefinder just now?" ”

Shen Wanqing said: "There are so many people, I don't have a chance to shoot." ”

Lin Yuan said: "You go back in a while, discuss with the staff, take a picture of the stereo rangefinder, and pay attention to the size of the front objective." ”

Shen Wanqing said: "What is the use of shooting this? ”

Lin Yuan said: "The clarity and magnification of the telescope imaging are related to the size of the objective lens, and with the size of the objective lens, we will definitely be able to analyze some things, such as: if we are engaged at sea, how far away they can see us." ”

Shen Wanqing nodded, turned around and went back, and quickly took the photo back, at this time Wilhelm II came to Lin Yuan and said with a smile: "I thought of an interesting thing, I don't know if you can know it, let's go, I'll take you to see it." ”

Wilhelm II took Lin Yuan to the side and walked more than 100 meters, only to see a room set up in the open space, the people outside the house saw Wilhelm II coming and hurriedly saluted, Wilhelm II took Lin Yuan into the house, the room was not big, there was a long table in it, and a huge box was placed on the table.

Wilhelm II said: "Now can you guess?" ”

Lin Yuan said helplessly: "Are you an immortal when I am?" I can guess things on the partition! ”

Wilhelm II smiled and said, "Of course not, I'll give you some interesting hints." Saying that, Wilhelm II picked up an iron chain from the table, and then said to Lin Yuan: "Have you ever seen this thing?" It is used a lot in your China! ”

Lin Yuan glanced at the iron chain, and saw that there was a cone-shaped thing at the end of the iron chain, Lin Yuan understood it at a glance, so he said: "Of course I know what this thing is, this is a sounding hammer, and when the ship is sailing, this thing is used to measure the depth of the seabed." ”

Wilhelm II smiled and said: "Very good, I almost forgot, you also have quite a bit of experience in the navy. Wilhelm II opened the box, pointed to the contents and said, "This thing will completely replace the position of the bathymetry!" ”

Lin Yuan's heart moved, as if he had guessed what was in the box, Lin Yuan walked in front of it, only to see that the box was a large flat plate, and the flat plate was densely arranged with small squares, Lin Yuan said: "If I guessed correctly, the thing in this box is ......"

Lin Yuan hesitated when he said this, not because he was not confident in his guess, he had already guessed: the thing in this box was an echo sounder, which was the same principle as sonar, but it was much simpler than sonar that needed to detect the echo position.

But Lin Yuan didn't know what the echo sounder said in Lu Daodao's language, so he had to change his words, pointed at it and said: "This thing can emit sound waves, sound waves will propagate in the seawater, and the sound waves will be reflected on the ship after hitting the bottom of the sea, so that the distance from the ship to the bottom of the sea can be determined, which is what you said: replacing the position of the sounding hammer." ”

"I don't think that's all there is to the echo sounder, because I didn't find the signal processing part, so I think this thing is just the base array of the echo sounder, sound and current can be converted into each other through some special crystals, if these special crystals are arranged, it forms a base array, I don't know if I'm right?"

After Lin Yuan finished speaking, Wilhelm II was surprised, and thought: "What is the origin of this kid Lin Yuan, he understands the latest techniques developed by our German Empire!" ”

Wilhelm II was surprised at the same time, Lin Yuan was also surprised, because the development of Europeans was indeed too fast, just now the Puran fire control system, stereo rangefinder have surpassed the original era, and the echo rangefinder has surpassed the era is even farther, in Lin Yuan's era, this kind of echo rangefinder did not appear until 1925.

Wilhelm II smiled and asked, "Is this all it can do?" ”

Lin Yuan asked, "What?" Is it useful for anything other than measuring the distance to the bottom of the ocean? ”

Wilhelm II said: "Of course, you can't guess, I'll give you some hints, you've heard of the Doppler effect, right?" ”

Lin Yuan nodded and said, "Isn't it the Doppler effect?" Of course I've heard about it, what's wrong? ”

Wilhelm II said: "Since you know the Doppler effect, you should know how to use this echolocator to determine the speed of our warships, right?" ”

Lin Yuan then understood that their original sounder also had the function of measuring speed, and in naval warfare, if you want to know the change in the distance of the road over time, you must not only estimate the speed of the opponent's warship, but also know the speed of your own warship.

Wilhelm II was happy to see that he had something that Lin Yuan didn't know, so he said: "Okay, there is nothing to see in this echo sounder, let's go, I'll take you to see something more important." ”

The group came out of it, and Shen Wanqing saw Lin Yuan's solemn face, so she asked, "What's wrong with you?" Isn't it just an echo sounder? I don't think that rangefinder is easy to use? Are you like that? ”

Lin Yuan whispered: "I'm not worried about the echo sounder itself, echo detection is like a key to a treasure trove, inside the treasure house, is the entire underwater weapons world, sonar, submarines, I'm really afraid that they will get the submarine out, do you know it?" Even if they come up with a submarine now, we can't guarantee 100% defeat with the existing means! ”