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Security devices and alarm systems of objects. Schemes, articles, descriptions

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Security devices and object signaling

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Car alarm with IR control



Section Car. Security devices and alarms. Recently, the interest of motorists in electronic systems for opening and closing doors (central locking) has begun to increase. This is due to the increased theft of radio tape recorders and other valuables from car interiors. As a rule, setting only a simple alarm does not give the desired effect, since the thief has time to remove the radio and leave the car in a few minutes. Therefore, car owners began to install alarms with central locking drives. This article is about a homemade central locking system based on the Atmel AT90S2313 microcontroller. For a remote command transmission system, infrared (IR) radiation is used. This choice is based on the fact that most radio amateurs do not have the equipment for setting up high-frequency transceivers, as well as the experience of assembling them. The use of IR beams is facilitated by the fact that ready-made IR receivers for household equipment are commercially available, containing the entire necessary set of amplifiers and detectors and having an output with logic levels suitable for direct connection to a microcontroller ... >>

Thermometer on microcontroller



Section Microcontrollers. Below is a diagram of a simple PIC thermometer. The indicator (in my case BA56-12SRWA) is used with a common anode. Temperature sensor DS18B20 (resolution 0.1'C) or DS1820 (resolution 0.5'C). The program itself will determine the type of sensor. If there is no sensor on the line, Err flashes. When the measured value is outside the measurement range, --- flashes. Measuring range -55'C to 125'C ... >>

Intercom Director-Secretary



Section Telephony. The proposed intercom (Fig. 1) has the following capabilities: control and reception and transmission are carried out via two unshielded wires, after the call is completed by the secretary of the director, the latter automatically switches to transmission. The device contains a base unit and a remote control (director). The base unit has an amplifier (VT4, VT5, DA1), a control unit (VT1, VT2, K1), a single vibrator (VT3, K4), a VA2 speaker and switching relays K2, short circuit. The device works as follows. In the initial state, transistors VT1, VT2 are open, relay K1 is on, contacts K1.1 are open ... >>

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Articles on security devices and signaling facilities

Articles on security devices and signaling of objects; schemes of security devices and signaling facilities; descriptions of security devices and signaling facilities: 154 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

Battery wrench 09.06.2000

The American Joe Piccone created a sliding wrench, the jaw opening of which is changed by pressing a button: the screw that rearranges the movable sponge is rotated by a micromotor. Two XNUMX-volt batteries are hidden in the key handle.

It's only a prototype so far, but Piccone plans to start production in less than a year.

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