With the advent of digital audio, the tape cassette, like its relatives (floppy disks with vinyl records), pretty soon turned into stylish pictures, losing its original meaning. We will not write it off and find out what it was made of and how it works. And also consider what can be done from old cassettes that have outlived their own.
What is a tape cassette and "what it is eaten with"
In Soviet stores, this miracle of technology was called MK. Many domestic consumers sneered at the primitiveness of the name. After all, it stands for "tape cassette." In fact, MK was honestly stripped from the original English Music Cassette.
By the way, the usual phrase “tape cassette” is not quite correct. This storage medium (used to record sound) was widely used not only in tape recorders, but also in voice recorders, answering machines, and computers. Therefore, the official name of the device is “Compact Cassette”. Less commonly used is the term audio cassette.
At one time, this medium was a breakthrough in the field of audio recording. After all, MKs were small and easy to handle, while plates and bobbins took up a lot of space and easily failed.
In the period from the 70s to 90s of the twentieth century. cassettes were the most popular means for recording and listening to music all over the world. Thanks to them, the size of the players decreased significantly, and they became portable. Also, we should be grateful to them for the appearance of personal music players.
Description of the tape cassette
At the peak of MK's popularity, more than a hundred companies were engaged in its production. Despite this, they all adhered to a single standard. This guaranteed the versatility of the compact cassette. Buying it in Japan, you could be sure that it would work in German, Soviet, and American tape recorder or player.
Let's look at what a typical MK consisted of.
All its parts were enclosed in a protective plastic case. Its dimensions are just the typical size of a tape cassette. It is equal to: 100.4 x 63.8 x 12 mm.
In cheap MK, this part was solid. This did not allow her to repair and disassemble. For more expensive ones, it consisted of halves twisted by tiny cogs (4 or 5 pcs.).
As for the color of the case, it was originally colored. Later MK began to make of less durable transparent plastic. This was due not only to its cheaper cost, but also to the fact that it allowed him to see what was happening inside the cassette.
Inside the Music Cassette there are 2 miniature bobbins with a diameter of 2-2.2 cm each. The ends of the magnetic tape are fixed on them. Each middle of such a core has an opening with 6 teeth. They allow the shafts of the tape drive of the player to control the cassette.
If the tape is completely wound on one of the bobbins, the diameter of the circle is 5.2 cm.
In both lower corners, the MK is located on a tiny guide roller. When the tape moves, it is they who set its position strictly along the axis of the housing.
At the bottom in the center is a magnetic screen and a hold-down spring with a felt pad. It is needed so that the tape is pressed as tightly as possible to the magnetic head, but is not injured. It also cleans the film of possible dust.
There are several technical holes on the MK case, which include elements of the tape drive mechanism of the reproducing device. For example, these are 2 symmetrical round holes at the bottom, not far from the pressure spring. Or the two rectangular slots for the eraser head surrounding it (in case of overwriting the cassette).
In addition, later MK models had special slots on top that "helped" the tape recorder "determine" the type of film used automatically.
Features of the film in MK
The heart of any cassette and at the same time its memory is magnetic tape. All information is recorded or rewritten on it. For this, 2 tracks (mono) or 4 (stereo) are used.
The standard film speed is 4.76 cm / s. In later two-cassette recorders, it became possible to transfer from one MK to another in accelerated mode: 9.53 cm / s.
As in reels, the cassette tape is created on the basis of a polymer film coated with a layer of powder of magnetic metals or their oxides.
In the first cassettes, they were coated with Fe 2 O 3 . However, the quality of recording and reproducing MK of this type was significantly inferior to the film based on CrO 2 . Subsequently, SONY developed a technology for the production of a two-layer tape with oxides of chromium and iron. She better transmitted the recorded, but at the same time there was a more capricious film coated with metal powder.
Each of the above types of coating had its own color and scope.
- Brown is Type I based on Fe 2 O 3 .
- Black - the so-called Metal Type IV.
- Dark blue based on CrO 2 - Type II.
- Type III - mixed film. Brown on one side and dark blue on the other.
- There is also a white tape in cassettes. This is a record. That is, a film that does not contain a ferromagnetic coating, and hence the recording. In addition to white, rakord can be transparent or with red marks for hitchhiking.
Despite the difference in coverage, MK tape has the same width - 3.81 mm.
The standard film thicknesses are 18 microns and 27 microns. In the first case, the tape is designed for 90 minutes of operation. In the second - for an hour. These species were the most used. Although at different times MK appeared for both 10 minutes and 240. However, films for over 90 minutes were too thin and unreliable.
Compact cassette for voice recorder
As mentioned above, the classic MK has parameters of 100.4 x 63.8 x 12 mm. Especially for voice recorders and answering machines, the so-called microcassette (MMK) was developed. Its dimensions are twice as modest as that of a traditional MK: 50 x 33 x 7 mm.
Although the principle of operation of the tape cassette and MMK is similar, the internal device is not only different in size.
- The recorder has a double set of springs and felt pads.
- The tape length is not 90 minutes, but half an hour or an hour.
- Film speed: 2.38 cm / s.
- To save space in MMK there may not be a record.
- Unlike conventional cartridges, these do not have a through channel, and the placement of the pinch roller and heads is somewhat non-standard.
Despite the lesser popularity and narrow application specificity, microcassettes cost more than usual.
The principle of operation of the MS
Having dealt with the MK device, you should find out how it works. At the heart of everything is the principle of magnetic recording.
The film in the cartridge is coated with a ferromagnetic composition (based on Fe 2 O 3 or CrO 2 ). When it is pulled in front of an electromagnet (which receives power by amplified currents generated by a microphone), changes in magnetization occur in metal particles (correspond to those current fluctuations that were caused by sound). Thus, data is recorded on the tape, that is, recording is performed. Theoretically, this can be not only sound, but also video, and other information.
Its reproduction occurs by pulling the tape through a similar magnet in a tape recorder or player. Only this time he "reads" the "figure" formed by the particles and transforms it into sound. And through the amplifier and loudspeaker delivers to the speakers.
As you can see, all ingenious is simple. However, to get to this, the cassette had to go through many transformations.
A brief history of MK
"Mom" of tape cassettes (photo below) can be considered reels with magnetic tape, and "grandmother" - phonograph records. The aim of the invention of all these devices was the desire of mankind to preserve music or other sounds in eternity. However, it was not possible to make a long record on gramophone records (appeared back in the 19th century). The bobbins were bulky and required constant rearrangement in places.
In the early 30s. XX century There was an idea to combine the supply and receive coils of the tape recorder in one case. The first experiments of this kind were carried out in pre-war Germany. Already in 1935-1936. The first compact cassette was designed. True, she worked on a wire. The outbreak of World War II halted the development of this technology.
After the war, in the early 50s, the company Loewe Optaphon released the world's first tape recorder using just the cassette format in which the film was looped. This invention provided an incentive for the development of this technology. Throughout the decade, several variations of the compact cassette came out.
A new milestone in the history of MK is the cassette of the American company RCA. She most of all looked like the carrier known today. The main difference was the dimensions: 197 × 127 × 13 mm. Despite this, it allowed to record and play audio for only an hour (30 minutes on each side) at a speed of 9.53 cm / s.
In the next few years, on the basis of this development, a format of four tracks emerged, and later of eight. Such MKs were widely used only in the USA before the advent of the compact cassette.
1963 became a landmark. It was then that the Dutch company Philips created the world's first full-fledged tape cassette. Due to its modest size, it received the name Compact Cassette, which was assigned to this product.
Fearing that the company's competitors would slightly improve their invention and drive it out of the market, Philips did not patent the technology and allowed everyone to use it. Soon cassettes a la Philips began to produce other companies around the world. They quickly replaced all other developments in this field.
By the way, the technology for the production of tape cassettes in the USSR was also "borrowed" from the Dutch. True, with a lot of shortcomings. According to eyewitnesses, in an effort to meet the needs of all residents of the country, MKs were made of worse quality than foreign counterparts. It got to the point that the production did not even have time to tighten all the bolts on the cassette. In addition, the materials from which the film was made were of the lowest quality, which is why tape recorders often chewed it. And after several rewrites, she completely failed. Therefore, despite the fact that the tape cassettes (photo in the article) of such manufacturers as Sony, Philips, TDK, Denon, Agfa, BASF were 2 times more expensive (compared to Soviet ones), buyers tried to use them.
The next stage in the evolution of MK was the invention of magnetic tape for them based on CrO 2 . Thanks to this, the recording quality is better. Now compact cassettes were able to drive bobbins out of the market (which they continued to use mainly only during studio recordings).
The incredible accessibility and ease of handling of these media has led to the emergence and development of piracy in relation to the copyright of musicians. Buying clean MKs and copying from others was much cheaper than purchasing ready-made tape cassettes with recordings of artists. In the USSR (where copyright did not exist), this problem did not appear. But the appearance of these devices stimulated the development of rock music, which official censorship did not very welcome.
Compact cassettes reached their peak of popularity between 1985-1990. It was during this period that their largest number was produced and sold.
In the first five-year plan of the 90s MK continued to hold positions. However, since 1996, they began to be actively crowded with compact discs. Unlike cassettes, more information was placed on them, and they did not require rewinding.
In the period 1996-2000. these carriers coexisted. Although the cassettes in many respects lost to discs, not everyone still had devices for reading the latter. And the cost of their production was higher than that of MK.
With the advent of the new millennium and the digital era, cassettes were almost completely displaced from the market.
Compact cassettes today
Although this media is outdated, it continues to be produced. In most cases - for retro fans. Although more often the surge of interest in MK is associated with fashion trends.
For example, in 2014, a movie from Marvel - Guardians of the Galaxy was released. One of the main characters, nostalgic about the past, listened to music on the Sony Walkman player. The desire of the audience to imitate him led to the fact that in the same year 10 million cassettes were purchased, and the demand for them in the USA continues to grow for a year.
It is noteworthy that in 2017 the long-awaited continuation of the tape “Guardians of the Galaxy 2” was released, in which the father of the main character broke his rare player. Let's hope this doesn't hurt the sales of compact cassettes.
Scope MK
From the very moment of its emergence, audio cassettes were inferior to gramophone records and reels. Almost from the very moment of their appearance, they were positioned as goods for mass consumption. The fact is that the playback quality of records on plates and bobbins has always been significantly higher than that of MK (like modern digital discs). Because of this, professionals rarely worked with them.
So, where are these storage media used. In addition to tape recorders and players, MK often listened in cars instead of the usual radio. By the way, when the cassette technology was still in the process of being finalized, radios were already manufactured for them.
If in the USSR voice recorders were not particularly common (compared to tape recorders), then in other developed countries they were used more than widely. Until the advent of the dictaphone format, almost half of all manufactured MKs were used in speech recording devices. They were used by secretaries, journalists, businessmen, writers and, of course, spies (where without them).
Considering the scope of MK, it is worth paying attention to another device that is familiar to most citizens of the USSR only from films. This is an answering machine. All the same compact cassettes were used to record a message on it.
MK instead of a floppy disk
At the dawn of the advent of personal computers, manufacturers faced the question: what to use as a medium? Diskette technology was still raw, and punch cards were outdated. The solution was tape cassettes. They (as well as drives for reading them) were much cheaper than floppy disks and attributes to them.
By the end of the 70s. home PCs recorded data on tapes. Initially, niches for MK were built into them. The technology was later simplified. Now a tape recorder was connected to the computer, which recorded / read the necessary data.
For immigrants from the USSR, this method of using cassettes became available only in the 80s. During this period, Soviet industry pleased its citizens Companion PC. Its design and device was honestly stolen from the British counterpart ZX Spectrum.
In fairness, it is worth saying that in most families with a Companion, it was used not so much for work, but for entertainment. To this day, many people gather dusty old games on tape cassettes in dressers. And in the late 80s and even early 90s for schoolchildren, they were the ultimate dream. Like a VCR or player.
Crafts from MK
In contrast to European countries and the United States, in the open spaces of the former USSR there is no such widespread nostalgia for this medium. On the contrary. Those who still have old tape cassettes in their bins do not know where to put this "happiness". Therefore, they come up with the most unimaginable ways to use them.
Wallets, handbags, lamps, furniture, paintings and even players are made from cases. Oddly enough, but some of the most popular crafts from old tape cassettes are caskets. Moreover, they are made not only from the bodies of several MKs, but also knitted from the magnetic tape itself.
Such boxes from old tape cassettes and crafts of a different kind are very popular. They are made not only for themselves, but also for sale. In almost any country in the world, on specialized sites you can buy both MK products and almost any tape cassette. Crafta.ua (Ukraine), Fair of Masters (RF), Amazon (USA), etc. - this is just a modest list of resources where such creations are sold.
So if you are the proud owner of several of these media in good condition, you can sell them or do something beautiful.
There is no single way how to use tape cassettes so that they are good or at least recapture the money spent on them. In any case, you should trust your own imagination. And she rarely fails. And since nothing comes to mind, you can put them back in the dresser and wait for the popularity to come to this device and to us.