Random sections


Among the remarkable technical achievements of the XIX century is not the last place is occupied by the invention is a recording. The first device that allows you to record sound, was created in 1857 by Leon Scott. The principle of operation phonoautograph it was very simple: the needle, which transferred the sound vibrations of the diaphragm, the curve is drawn on the surface of a rotating cylinder covered with a layer of soot. Sound waves in this device would be prepared as a visible image, but no more - it is clear that reproduce sound recorded on carbon black was impossible. The next important step in this direction was made by the famous American inventor Edison. In 1877, Edison created the first "talking machine" - phonograph allows for not only the recording but also the sound playback. On his invention Edison said this: "Once, when I was still working on improving the telephone, I once sang over the phone diaphragm, to which was soldered steel needle. Thanks to shake plates needle pricked my finger, and it got me thinking. If you could write these oscillations of the needle, and then hold the needle on a record again, why not speak to the plate? I tried at first to miss the common tickertape at the edge of the telephone diaphragm and noticed that he had received some kind of alphabet, and then, when I made a tape recording again to go under the needle, I heard, however, very weak, "Hello, hello." Then I decided to build a device that would work clearly, and gave instructions to my assistants, saying that I invented. They laughed at me. "

phonograph principle was broadly the same as that on the phone. Sound waves via govornoy tubes were brought to a very thin plate of glass or mica, and a cutter attached thereto, recorded on the rapidly rotating shaft, covered with tin foil. Foil traces obtained whose shape corresponds to vibrations of the plate and therefore falling on it to sound waves. This strip of tinfoil can be use to produce the same unit of the same sounds. With a uniform rotation of the cutter strip attached to the plate passed along his earlier slot. As a result, the cutter plate is cited in the same vibrations that before she herself referred to it under the influence of voice and sound instrument and begins to sound like a phone membrane. Thus the phonograph reproduced every conversation, singing and whistling.

The first devices Edison, started in 1877, were still very imperfect. They wheezed, nasal, overly amplified some sounds, it is not reproduced other, and in general, more like parrots than reproducers of human speech. Another was the lack of them is that the sound could be distinguished only my ear to the diaphragm. This was largely due to the fact that the roller is moved over the surface is not enough even that could not make a perfectly smooth. The needle, passing from one recess to another, experiencing the natural oscillations transmitted in the form of strong noise.

Edison worked hard to improve the phonograph. Especially a lot of the problems he encountered with audio playback "to" who did not want to be recorded. He later recalled: "For seven months I have been working almost 18-20 hours a day over the word" spice ". How many times I have repeated in the phonograph: spice, spice, spice - the device stubbornly repeated to me the same thing: petsiya, petsiya, petsiya. With the mind you can get! But I have not lost courage and persistently continued his work until overcame the difficulties. How difficult was my task, you will understand if I say that the traces obtained on the cylinder at the beginning of words, had in depth no more than one millionth of an inch! It is easy to make amazing discoveries, but the difficulty is to improve them so that they get practical value. " After many experiments, it was found more or less suitable material for cushions - an alloy of wax and some plant resins (this recipe Edison kept secret). In 1878 he founded a special company for the production of phonographs. At the same time a broad advertising his invention was deployed in all the newspapers. I assure you that phonograph can be used to dictate letters, publications audio books, playing music, foreign language learning, recorded telephone messages and many other purposes.

But, alas, none of these promises have not been fulfilled, even in 1889, when a new phonograph was constructed, many of which had no previous shortcomings.

The principle of its action remains the same. W wax cylinder was rotated are in the box K motor with a very calm and steady progress. Regulator of G by switching on and off resistances ruled cylinder speed (125 rev / min). Lever A, supports govornuyu tube and plate, resting on a sled. These slides moved along the guide bar F with a nut screw-threaded the M, which lay on the main roller screw, which had small cuts and form a cylinder axis C. Cutting this represented the exemplary work of mechanics and had a hundred helical turns per inch. Two levers A and B were top for receiving the nuts from the main stem. Plates phonograph consisted of very thin glass; One of them had a sharp tool for recording records vibrations on a wax cylinder, the other - a blunt tool for playback. A third, somewhat more robust plate was equipped with a small sharp chisel to the distruction of wax cylinders again grind, and thus use them for new recordings. To enhance the sound tube used with socket.

The writing part is a metal ring set into a circular aperture, the space on which it was closed by a lid with a bell. When it comes to this socket, the sound waves reach the diaphragm and brought it to oscillate. Below the middle of the diaphragm was attached a thin tip of a writing, with which he carved wax shell drum groove, more or less deep, respectively, of the diaphragm vibrations. The diaphragm with its accessories supported on an arm that was attached to the moving device and moved along with the latter when the drum rotates from right to left. To this movement took place in accordance with the rotation of the drum, on a sliding device was reinforced a second arm, which at its end resting on the screw shaft, leaning on his part of the nut. Thus, when the spindle moves the sliding device, as well as the spindle is connected to the endless cord reel shaft, the sliding device and with it the pin moved in accordance with its rotation, and Brad carved wax weight helix. As long as the aperture is not fluctuated, brad carved groove of uniform depth, but as soon as the diaphragm begins to waver under the influence of sound waves, the depth of the groove all the time either decreased, or increased. This undulating strip then used to drive other similar aperture, to which was attached a sliding groove for brad.

However, new and improved phonograph not received wide practical application. In addition to high prices, prevented the spread of its practical shortcomings. Roller could not hold a lot of information and filled in a few minutes. More or less significant correspondence require a large number of rollers. After several auditions copy destroyed. Transmission apparatus itself was far from perfect. In addition, it was impossible to obtain copies of the wax roll. Every entry was unique and the corruption of the roller was lost forever.

All these shortcomings have been successfully overcome by Emile Berliner, who in 1887 took out a patent on the other sound recording device - the phonograph. Although the principle of the device gramophone and phonograph was the same, the gramophone had a number of significant differences, which provided him with the widest distribution. First of all, the needle in the recording apparatus Berliner is parallel to the plane of the diaphragm and the devil twisting lines (rather than grooves, as in Edison). Also, instead of bulky and uncomfortable roller Berliner chose the circular plate.

Recording took place in the following way. On the large-diameter disc with edge set for recording sound polished zinc disc. It was poured on top of the wax solution in gasoline. Disc tub receive rotation from the handle through the friction gear and the gear system and connected the drive spindle rotation with a radial course of the recording membrane, reinforced at the front. This movement is achieved by the recording device helical line. When gasoline evaporates, the CD remained a very thin layer of wax, and the disc was ready to record. Application of the sound groove Berliner produced almost the same as Edison, with a recording membrane tube equipped with a small horn and transmit their vibrations iridium tip.

The main advantage of Berliner recording method consisted in the fact that a disk can easily receive copies. For this purpose, first of all the recorded disc was immersed in an aqueous solution of chromic acid. Where the surface of the disc was coated with wax, acid is not exerted any influence on it. Only audio grooves as recording tip cut off to the surface wax disc dissolved zinc with an acid. Thus sound groove etched to a depth of approximately 0 1 mm. The disk was then removed and washed with wax. As such, he could serve for the reproduction of sound, but in fact was the only original copper electroplating for making copies.

electroforming principle was discovered in 1838 by Russian electrical engineer Jacobi. We have already mentioned electrolyte - a liquid conductive through an electric current. A feature of electrolytes is that they break down into molecules of positive and negative ions in solution (or melts). This enables the electrolysis - chemical reaction that takes place under the influence of an electric current. To carry out the electrolysis bath is placed in metal or carbon rods, are connected to a constant current source. (Electrode connected to the negative pole of the battery is called a cathode and the electrode connected to the positive pole -. The anode) electric current in the electrolyte is a process of ion motion to the electrodes. Positively charged ions move toward the cathode and negatively charged - to the anode. At the electrodes occurs ions neutralize the reaction that giving or receiving extra electrons missing, are transformed into atoms and molecules. For example, each ion of copper on the cathode receives two missing electrons and deposited thereon in the form of metallic copper. This precipitate gives an accurate picture of the cathode relief. This latter feature is just used for electroforming. With a copy of the copied object is removed (matrix) that represents the opposite of their negative image. Then a copy is suspended as a cathode (negative pole) in the plating bath. In the taken material from which a copy was produced as the anode (positive pole). bath solution should contain the same metal ions.

Similarly he acted Berliner - he dipped zinc disc in a bath with a solution of copper salts and connect to it the negative pole of the battery. In the process of electrolysis on the disk layer of copper is deposited in the thickness of 3-4 mm, repeat exactly all the details of the disc, but with opposite relief (ie in place of the grooves obtained lumps, but mimic all their twists). Then, the resultant was separated by a copper zinc copy disc. She served as a matrix, which can be pressed flat disc-plates from some plastic material. In the beginning was used for this purpose, celluloid, ebonite, various wax mass and the like. The very first in the history of the gramophone record was produced by Berliner in 1888 celluloid. Gramophone records, received in the early 90s in the sale were made of hard rubber. Both of these materials are not suited for the intended purpose, as the compact poorly fed and therefore not accurately reproduce relief matrix. Having done a lot of experiments, the Berliner in 1896 created a special shellac mass (in its composition consisted of shellac - resin of organic origin, barite, fly ash and some other substances), which then remained for decades the basic material for the production of records.

Playing records occurred on a special device - the gramophone. The main part of the instrument's pickup here was mica plate, clutch lever with a clip, which is inserted in the removable steel needles. Between the clamp body and the membrane are placed rubber gaskets. Initially, the gramophone was set in motion by hand, and then began to be installed on a box with a clockwork mechanism.

As a recording device, and the first gramophones Berliner were very imperfect. Hiss, crackle and distortion were their constant companions. However, this invention has a huge commercial success - for any gramophones ten years spread throughout the world and penetrated all strata of society. By 1901 it was released for about four million records. Phonograph could not compete with the creation of Berliner and Edison had to curtail their production.

Allowed copying with active link to the source
© 2016 All Rights Reserved