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Various computer devices. Schemes, articles, descriptions

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Power amplifier for CB radio (on lamp)

Section RF power amplifiers. Most portable radios on the 27 MHz band have a transmitter with an output power of no more than 1-2 watts. The sensitivity of the receivers of such radio stations usually lies in the range of 3-0,5 μV / m. As a result, even with the use of a high-quality outdoor antenna, the communication range at which reliable reception is provided is not very high. It makes no sense to increase the receiver sensitivity further than 0,5 μV/m, since the noise level increases, both atmospheric and the noise of the receiver input elements. So the real way to increase the radio communication range on the SW is only to increase the output power of the radio station transmitter ... >>

Programmable code lock

Section Security devices and signaling of objects. Unlike previously published code lock schemes, this one has the ability to change the lock code using three buttons, i.e. a sufficiently high secrecy mode is provided with a minimum number of buttons. Let's consider the order of dialing (recording) the desired code into the lock's memory. The counters DD6, DD7 are first reset with the reset button SB6, after which a two-digit code of numbers (0 ... 7) is written to them using the buttons (SB4 and SB5). The dialed code indication is read by the extinguished LEDs (VD1...VD6) in binary terms. To protect against bounce of the button contacts, RS flip-flops are used on the IC DD3 ... >>

Thermostat for mini-incubator

Section Power regulators, thermometers, heat stabilizers. Several types of mini-incubators are produced in the CIS. The temperature in them is maintained by a mechanical thermostat, there is no indication of exceeding the limit temperature inside the incubator. To replace the mechanical thermostat, the proposed electronic one (Fig. 1) with additional service functions is intended. The accuracy of maintaining the temperature inside the mini-incubator is 0,2°C. The temperature can be adjusted within 37...39°С. The operability of the thermostat is maintained when the mains voltage fluctuates within ± 20% of the nominal value ... >>

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Articles on various computer devices

Articles on various computer devices; diagrams of various computer devices; descriptions of various computer devices: 32 articles



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Latest news of science and technology, new electronics:

Blinking of the magician and his audience 19.05.2024

Magic and illusions have always captured the attention of the public, but what happens behind the scenes of the magician and in the brains of his audience? Scientists from the UK decided to solve this mystery by conducting a new study involving ten illusionists of varying experience. Illusionists, some of whom had been practicing magic for more than half a century, others for only six months, were invited to demonstrate the same trick - the popular coin trick. Recordings of their performances during training and on stage showed that each of them began to blink significantly more often at the moment of performing the trick. The study's findings indicate that magicians' blink rate may be related to unconscious aspects of their performance. At the same time, as scientists have found, spectators also begin to blink more often, following the movements of the illusionist. This observation supports the idea that magicians may be catalysts for blinking in audiences. Additional research has shown that magicians blink more often during ... >>

Ultrasonic coffee machine 19.05.2024

Iced coffee has become an integral part of coffee culture in recent years. Therefore, engineers from the University of New South Wales decided to improve its preparation. They have developed an ultrasonic coffee machine that reduces the cold brew time for ground coffee beans from 12-24 hours to significantly less time. Iced coffee, or "Cold brew", is popular due to its smoothness, low acidity and low bitterness. It is prepared by steeping ground coffee in cold water for a long time. Unlike traditional hot brewing, which often imparts bitterness to coffee, cold brewing extracts more delicate and complex flavors from the coffee beans. The innovative system, presented by a team of engineers, introduces ultrasonic technology into the coffee preparation process. The system uses ultrasonic waves to speed up the process of extracting oils, flavor and aroma from ground coffee. This allows you to significantly reduce the time ... >>

The speech of sperm whales is similar to that of humans 18.05.2024

In the world of the ocean, where the mysterious and unknown coexists with the studied, sperm whales, with their huge brains, are of particular interest to science. Researchers, working with a huge array of audio recordings collected during the Dominica Sperm Whale Project (DSWP) - more than 8000 recordings, seek to unravel the secrets of their communication and understand the structure and complexity of the language of these mysterious creatures. By studying in detail the recordings of 60 sperm whales in the eastern Caribbean, scientists have revealed surprising features of their communication, revealing the complexity of their language. "Our observations indicate that these whales have a highly developed combinatorial communication system, including rubato and ornaments, which indicates their ability to quickly adapt and vary during communication. Despite significant differences in evolution, sperm whales have elements in their communication that are characteristic of human communication," says Shane Gero, a biologist at Carleton University and director of the CETI project. Issl ... >>

Random news from the Archive

Bats are the main carriers of viral diseases 19.07.2017

Researchers from the American organization EcoHealth Alliance have compiled a "global threat map", placing on the map areas that can become a source of a viral epidemic that threatens human health, reports the BBC. Scientists have studied mammals of various ranges, infectious diseases carried by these animals, and the possibility of their contact with humans.

In particular, they studied 586 types of viruses that infected 754 species of mammals (188 types of viruses are zoonotic infections that can infect humans), with special attention paid to those viruses that until recently were practically ignored by researchers. Based on the results of their research, experts have created a map of the habitats of wild animals, along with the spread of infectious diseases that they carry. As it turned out, the potential places of possible occurrence of epidemics differ for different groups of mammals, but the threat from bats in many respects exceeds the danger of other animal species. In particular, bats appear to have been responsible for one of the worst epidemics of recent years, the Ebola outbreak.

The researchers named 17 zoonotic infections that any member of this order can carry, and epidemics caused by bats can break out anywhere in the world, but the greatest danger comes from South America. In addition, scientists noted ten infections carried by any species of primates and rodents.

In general, the authors of the work stated that any epidemic occurs due to human impact on the environment, therefore, in order to minimize the risk of a new epidemic, it is necessary to limit human contact with wildlife as much as possible, in particular, stop hunting and destroying the habitual habitats of wild animals.

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