Lin Gao Qiming

Chapter 1947 Card Duplication
So Feng Nuo adjusted the data processing mode of the tabulating machine.

Previously, tabulators were designed to read punched cards column by column. In this mode, even if each column is read in only 0.1 seconds, it takes 80 seconds to read 8 columns, which is not counted for card transmission. time.After careful consideration, Feng Nuo believes that in practical applications, not all columns of each punch card need to be counted or accumulated.

Taking salary statistics as an example, it is impossible to only have relevant data on the amount of salary on the punched card.On the contrary, more columns should be used to save information such as the worker's name, gender, department, job type, job number, etc., and information such as name location code, department code, job type code, job number, etc. is not necessary for statistics.

Therefore, under the existing conditions, it is enough to count only one item of data at a time. Even if a certain item of data has multiple digits and is distributed on multiple columns of punched cards, it is feasible to process only one bit at a time. Anyway, The statistical results also need to be manually summed at the end.

In this way, when the tabulator processes each card, it only needs to read a certain column of numbers on the card and accumulate them, which naturally speeds up greatly and saves power.

Feng Nuo spent another two days simplifying and modifying the device, and finally stabilized the card processing capacity of the tabulating machine at more than 3000 cards per hour, which should be able to meet the general statistical calculation needs of the Senate.The fly in the ointment is that if a certain data to be calculated has 3 digits, it needs to go through the machine 3 times.From the perspective of ease of use, it is still not convenient enough.But now Feng Nuo is to verify the technical ideas, and more improvements need to be made in the practical stage.

After conquering the tabulation machine, most of the mechanical mechanisms and relay control mechanisms have been successfully developed, and other types of machines are just changing the design, adding, subtracting, and combining parts.In the punched card machine system, the sorting machine, which is second only to the tabulating machine in importance, is to change the relay on the tabbing machine used to control the number of dials and realize the accumulation function to separately control multiple card feeding mechanisms, Cards punched on different numbers of the base column are delivered to different card pockets.

However, just as he was gearing up to take down the sorting machine in one go, a new problem appeared.

Due to the quality of the cards, the card materials that have been shipped have been severely damaged during the intensive testing of the tabulation machine in the past few days, and the experimental materials will soon be in short supply.

Feng Nuo had no choice but to put aside his eagerness to try the sorting machine and develop a duplicating machine first. With the duplicating machine, existing cards can be copied at will, and the problem of card shortage will no longer exist.

He found the information of the IBM513 duplicating machine of IBM in the old time and space, the full name is "Automatic Reproducing Punch".This is a model that only appeared in the 20s. The principle is not difficult, but the structure of the machine is a bit complicated. Feng Nuo does not intend to copy it as it is, just build a prototype based on the principle.

He tried his best to draw a schematic diagram on the paper neatly. The core component of the copying machine is a set of linkage transmission mechanism that can place double rows of cards. When the template card passes through the processing unit, the brush of the card reading mechanism sweeps the card, The communication circuit activates the relay at the corresponding position, thereby controlling the punching mechanism of the new card processing unit to punch holes at the same position of the new card.This time, reading and punching needs to be done column by column.

However, Feng Nuo got stuck when thinking about the control of the perforating knife: the distance between the holes in each column on the perforating card is only a few millimeters, and he made the relay so large, how could it be possible to control multiple perforating heads at the same time? ?After thinking about it for a long time, I couldn't figure it out, so I had to take the half-baked schematic diagram and ask the veteran of the mechanical port for advice the next day.

I still came to look for Sun Li, and when I entered the office, I found that Zhan Wuya was also here.Feng Nuo has lived in the machinery factory for a long time, and he is familiar with Zhan Wuya. Knowing that he is a real person, he is not polite, so he directly spread out the "drawings" and asked questions.Zhan Wuya laughed loudly, pointed to an English typewriter made by Lingao next to him and said, "Go and see how that typewriter can type all the characters of more than 40 keys into the same position?"

Feng Nuo slapped his head, yes, he also has an English typewriter in his office, but he never thought of this.

Zhan Wuya went on to say, "This is the most basic problem in mechanical design. Apart from using the curved typesetting structure of a typewriter, there are many other solutions that can be solved. Don't think about mechanical design by yourself. Let us handle this matter professionally, you should honestly design your relay control scheme, the governor also asked about the progress of this project yesterday."

Because Feng Nuo actually doesn't understand mechanical design, the drawings he submitted to the machinery factory are basically just "schematic diagrams". For some structures that can be copied off-the-shelf, he copied past design drawings, but when it comes to production It still depends on the technical staff of the machinery factory to redesign.

Feng Nuo quickly reported some progress, and then patted his chest to promise that the research and development speed will be accelerated in the near future, please rest assured the leader.

The copying machine did not pass the test as well as the tabulating machine.

It was late in the evening when the prototype was delivered. First, we tested 1 copy and 10 cards respectively. After manual inspection, no problems were found. The copied new card was exactly the same as the template card.So Feng Nuo asked Qian Yuzhi and Li Jianai to try copying 1000 cards at once.

Due to the line-by-line copying, the speed of the copying machine is roughly similar to that of the unoptimized tabulation machine. It takes about 1000 hours for 3 cards, and Feng Nuo left work after explaining.The leader was very concerned, so Feng Nuo often worked overtime during this period. Today, he finally had some technical work, so he could only let Qian Yuzhi and the other two watch him.

When duplicating a small number of cards, you can check whether the perforations are consistent by overlapping the old and new cards against the light. 1000 cards can no longer be checked for correctness by manual methods.Therefore, Feng Nuo asked them to use a tabulation machine to check whether the perforations are consistent after copying.The method is to count whether the number of 0-9 in each column of the two stacks of cards is consistent. If the results are the same, the probability of the problem can be ignored.However, according to the speed of the current tabulating machine, the inspection time for each column is about 20 minutes, and it takes more than 80 hours for 20 columns, so the two had to be shifted at night.

The next morning, Feng Nuo went to the planning academy to have a small meeting, and he came to the office around noon.

He found that Feng Shan was leading Qian Yuzhi and Li Jianai to check whether the perforations of the cards were consistent with the light one by one. ——It has probably been checked for a long time, and the eyes of the three are a little lax, and Qian Yuzhi and Li Jianai have dark circles under their eyes.Feng Nuo was very surprised and hurried over to ask.

It turned out that Qian Yuzhi and Li Jianai had been checking the copy results of 1000 cards with a tabulating machine last night, but found that the number of 0-9 in a certain column of the new and old cards was not the same. The copied card had one less 3, but more a 4.That is to say, the duplicator made an error and mistakenly typed 3 instead of 4 on a certain card.So they're now trying to figure out which card was the problem.

"Great work attitude, stupid work methods," commented Vonno.He walked over to pick up the two stacks of cards that the three of them hadn't checked, and asked, "How much have you checked?"

"Two."

"Two."

"Two."

The three answered separately.

"Look, three people only checked more than 300 cards in one morning. We need to test 1 cards in the future, how many people do we need?" He handed the stack of cards in his hand to Feng Shan and said, "Find out 330 to come."

Then he asked Qian Yuzhi which list was wrong, and adjusted the position of the card-reading brush of the tabulating machine.He also divided the remaining stack in his hand into two stacks of 330 and 327.

Afterwards, Feng Nuo counted the 330 new cards found by Feng Shan and the 330 old cards he had allocated with a tabulating machine.

Ten minutes later, the statistics were over, and the result was the same.

"So, the wrong card must be in the other half." Feng Nuo pointed to the remaining two stacks of cards.

So he separated 327 cards from the remaining two stacks of 160 cards and entered them into the tabulating machine.This time it turned out that the wrong card was among the 160.

Feng Nuo divided this batch of cards into two parts, each containing 80 new and old cards in one-to-one correspondence, and took one at random to repeat the above operation.

……

A few minutes later, the scope of suspicion was narrowed down to 10 cards. Feng Nuo distributed the cards to Feng Shan and the three, and quickly found the wrong card.

Feng Nuo put the wrong card on the table and didn't look at it.Instead, he said to Feng Shan: "The purpose of our computer is to replace manpower to complete mechanical calculation work. It does the mechanical work, and you don't need to do it. What do you want to do? It is to think about how to drive it to work. Achieve your goal. Let me tell you, what is the reason for finding the wrong card like this just now?"

"Binary search method?" Feng Shan asked uncertainly.

Feng Nuo nodded, "It's not the same, but the idea is similar. If you think about why I asked Yuzhi and Kana to check whether two stacks of 1000 cards are consistent yesterday, you can think of many solutions. At least , you can enter 100 cards at a time, up to 10 times, and you will know which 100 cards are wrong. ——Of course, if you can think of this, you can also realize that binary search is the fastest. "

"We have a premise for doing this, that is, the probability of copying errors is very low. Otherwise, multiple punch cards are wrongly listed in the same column, and this method will not work. Therefore, yesterday we checked the results of 1 and 10 copies first, No problem."

"Facts also show that our estimate is in line with the actual situation. There are 1000 cards, that is, there are 80000 column copy operations. The two of them checked more than 30 columns from last night to this morning. In fact, only 1 column was found to be wrong, and the statistics found only a few a 3, and only an extra 4. This is what you know before looking for the wrong card, right? We have no other prior knowledge, so we can only assume that the probability of error of the replicator is 1/30000, regardless of The current error is caused by the accumulation of multiple cards in the same column, because the probability is lower and can be ignored for the time being.

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Next update: Volume 52 - Chapter [-] of Two Levels Raiders

(End of this chapter)