cicada

Chapter 926 Signal Guidance Station

Hearing Gao Ziheng's answer, Zuo Zhong immediately asked the other party to explain in detail that in terms of aviation technology, this is a rare professional talent in the Republic of China.

Gao Ziheng nodded and began to explain the development of night ground guidance or aircraft navigation in order to better answer his question.

"Deputy Director Left, since the American Wright Brothers invented airplanes, for a long time, airplanes did not have any navigation equipment, and relied entirely on pilots to visually observe landmarks and fly along mountains or rivers.

However, without the landmarks, how to keep the aircraft from getting lost in the air with large changes in visibility has become an important problem. The civilians and military forces of various countries have conducted relevant research on this and have come up with many solutions.

For example, the Americans invested in the construction of a large number of airmail flight signposts on the ground in the 20s. The main body is a huge arrow with a length of about 20 meters, spanning the entire United States.

These arrows are painted a bright lemon color, and there is a 15-meter-high tower near each arrow. There is a high-intensity gas lamp on the top of the tower to remind passing pilots to pay attention. (with easter eggs)
Thanks to this easily identifiable design, USPS pilots can see the arrow from dozens of miles away and follow it to the next arrow a few miles away. "

Speaking of this, the plane slowly stopped, and the secret agents dragged the ashen-faced Wu Xiwen out of the cabin. Zuo Zhong and the others also walked and chatted down the gangway, and came to a conference room at the airport.

Everyone found a place to sit down. Wu Xiwen was escorted to a corner, surrounded by a few small spies vigilantly. Gao Ziheng rubbed his sore thighs and continued to introduce.

"However, this method is expensive and cannot be used in foggy weather, which greatly limits the flight range of the aircraft. It was fine during the Heping period, but it seems a bit tasteless in the real period.

Some people refer to the experience of sailing and take the magnetic compass and sextant on the plane, but there are still problems. The speed of the plane is much faster than that of the ship, and these devices cannot play a role.

During the European War, Western science and technology developed explosively. Radio, as a new carrier that is invisible and ignores the weather, was regarded by various countries as a breakthrough for navigation.

So radio navigation technology came out one after another. The specific method is to install radio navigation beacons near the airport to help the aircraft fly to the airport and land accurately.

At the same time, the pilot judges the position through the signal strength of the beacon and the compass. The advantage is that it is not limited by time and weather, the working distance is far away, and the positioning time is short.

The disadvantage is that the radio anti-interference is poor and needs the support of the navigation station. Once the navigation station fails, the corresponding navigation equipment cannot be used, and it is prone to failure and poor accuracy.

The first aviation pointing station of the Republic of China was built in Huaniao Mountain, Zhejiang Province in the 16th year of the Republic of China, and the second one was built in Chengshantou, Shandong Province in the 21st year of the Republic of China, and the effect was not bad. "

"Wait a minute."

Zuo Zhong interrupted Gao Ziheng's introduction, and asked with some doubts: "Can the aviation pointing station you mentioned allow the Japanese to fly thousands of miles away to the mountain city to accurately bomb the Huangshan official residence?"

"Of course not."

Gao Ziheng shook his head, and replied helplessly: "This thing can only allow the pilot to roughly judge how far away from the airport, if it is bombing, it is necessary to find out the distance from the target to the airport, and the two are used in conjunction with each other.

If it was to bomb a city, that would be no problem. After all, the range of the target was large, and even a target could be hit. It was impossible to bomb a building, at least not with the skills of the pilots of the Japanese navy and army. "

Zuo Zhong nodded when he heard this. If someone else said this, he would put a question mark, but this man has fought against the Japanese Air Force many times, and he is very clear about the opponent's capabilities, so his evaluation should be objective.

After thinking for a while, he looked at the other party: "Director Gao, you just said that it can be done. Could it be that some countries have overcome the technical difficulties of radio navigation to achieve precise bombing guidance?"

"good."

As Gao Ziheng said, he took a piece of paper, drew two horizontal lines on it, one short and one long, and marked the words short and long on the side, then looked up to the left.

"Deputy Director Zuo, you are an intelligence officer and have taken telecommunications courses, so you should know the principle of Morse code. The so-called code is the regular combination of short and long tones to represent different meanings.

When I was studying in France, I heard that the British company Marconi was experimenting with a new technology. They used two radio stations to transmit Morse code, one for a short tone and the other for a long tone.

If the aircraft is flying in the middle area of ​​the two signals, it can receive short and long sound signals of the same strength at the same time. If it deviates, one of the signals will become stronger and suppress the other signal.

The pilot corrects the direction according to this, so the heading problem is solved. As for how to know whether the aircraft has reached the sky above the target, there are many ways. I think there are two more reliable methods.

One method is to calculate the mileage through the flight time, the error is relatively large, and then set up an auxiliary signal transmitting station in another place, and use the beams emitted by the two stations to converge to the target.

Assuming a war broke out, the bombers could strike a certain target precisely by relying on the signal guidance station established in the frontline positions. This method was probably used by the Japanese to bomb the official residence.

But this requires very reliable radio technology. I don't know if the Japanese have done any relevant research. That's what you, Deputy Director Zuo, are going to do. I'm just analyzing it purely from a technical point of view. "

Gao Ziheng not only explained the principle, but also drew a schematic diagram on paper, which is so simple that even people who don't know radio can understand it at a glance. (with easter eggs)
Gu Qi and the others looked at the note for a while, and they probably figured out the technology, and then a question came to their minds.

——If the situation is as Gao Ziheng guessed, where can the Japanese signal guidance station be located?
The Huangshan official residence is not the front line. It is the seat of the committee, and the surrounding area is heavily guarded. The electric reconnaissance vehicles of the Central Command and the Military Command often patrol the vicinity.

In this case, not to mention guiding the aircraft, I am afraid that the Japanese will be discovered as soon as they start the machine. The current monitoring records have not found any abnormal signals in Huangshan.

The spies who couldn't figure it out looked at Wu Xiwen in the corner, and found that the other party was looking at his nose and heart, sitting there motionless, as if he didn't hear what Gao Ziheng just said.

Zuo Zhong didn't look at the schematic diagram, but sat aside and put his hands on the table, tapping his fingers on the table lightly. After a long time, he slowly asked Wu Chunyang something.

"Chunyang, have you checked all the wires at the mansion, are there any wires with unknown purpose, especially those connected externally without the approval of the attendant's room.

The attendant's room communicates with military and political agencies in various places 24 hours a day. The Japanese can hide the signal guidance station in the official residence, but no matter where it is hidden, the signal station must be powered on. "

As soon as this remark came out, everyone immediately realized that yes, they were hiding in the mansion, so that even if the electric surveillance vehicle found the signal, it would treat it as normal communication and ignore it.

In addition, they checked the suspects before, and they checked who had gone out. Now it seems that the direction is completely wrong. The spy does not need to go out at all, and can guide the bomber directly in the official residence.

At this time, Wu Jingzhong and Gu Qi, who are good at observing words and expressions, noticed that Wu Xiwen's nostrils dilated, which is a signal that the brain needs more oxygen when emotional.

I didn't run away, let the deputy chief say it right, the signal guide station was real, and the devil got it to the committee's side, now I don't know how many people will be killed.

Since the Japanese can bring things like radio stations into the official residence, they can bring dynamite┴, I don’t know, but the security work in the attendant’s room is obviously not done properly.

Wu Chunyang also noticed this scene, and with an idea in his mind, he raised his voice slightly: "In order to prevent eavesdropping┴, the Yunxiu Building where the commissioner lives and the Songting where the wife lives will check the lines every month.

After the incident, we also checked and found no suspicious circumstances, but... the mansion is so big, it is impossible to determine whether there are any problems with the wiring in other places. I suggest that you thoroughly check the entire mansion. "

After finishing speaking, he turned his head slightly and saw Wu Xiwen's body shaking, and now he was even more sure that the deputy director's judgment was correct, otherwise the other party was fine and shaking.

Zuo Zhong also noticed Wu Xiwen's change, but he didn't expose it on the spot. The scene hadn't finished yet, so he got up and said goodbye to Gao Ziheng and Guan Shaoyu.

"Director Gao, Captain Guan, thank you for your help, we will leave first, please keep this matter a secret today, if anyone asks you, please contact me immediately."

"clear."

Gao Ziheng and Guan Shaoyu knew the seriousness of the matter and replied in unison.

With the relationship with the man in the official residence, no matter how small it is, it's a big deal. Just get the 100 barrels of aviation gasoline, and they don't want to get involved in other things.

Zuo Zhong was at ease with the two of them, and after shaking hands, he took his men and Wu Xiwen away, returned to the pier and boarded a naval patrol boat to return to the mountain city.

The dilapidated little robot boat turned up its horsepower and headed upstream with a chug of black smoke, leaving Guangyangba Airport behind in a short while.

Looking at the dark mountains on both sides of the river, Zuo Chong lit a cigarette and stood at the bow of the boat. Under the hazy moonlight, Chang Qiao became extremely docile and calm.

Suddenly, he heard the sound of a suona playing from the shore, thinking that making noise is strictly prohibited in the air defense control regulations, so he frowned and asked everyone what was going on.

Gu Qi and the others looked at each other, they couldn't see anything this night, they didn't know who did it, but Wu Chunyang stood up and explained a few words.

"Senior seat, there is a cemetery near here. Someone should be singing a funeral. When I was investigating the whereabouts of the servants of the mansion, I came here. Don't worry, there are no residents around here."

As long as there is no resident, Zuo Zhong, relieved, waved his hands and thought about the finishing work of the case. This matter is actually not complicated, and the case can be declared over after finding the signal guidance station.

This era is not like the later generations. The size of electronic products cannot be small, and the area of ​​official residences is huge. As long as there are enough people, it is necessary to find the equipment installed by the Japanese even if they dig three feet.

Zuo Chong listened to the sound of Huangqiang playing in the distance, raised his hand and flicked the cigarette butt into the pickle, ready to turn around and assign tasks. This was not an easy task.

But at this moment, he seemed to think of something, his body paused, and then he returned to normal, and he calmly arranged the search for the Huangshan official residence.

(End of this chapter)