Acoustic switch. Scheme, description

Free technical library

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Schemes of radio-electronic and electrical devices

Acoustic switch. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Clocks, timers, relays, load switches

Comments on the article

The proposed switch, the schematic diagram of which is shown in the figure, in addition to its main function - turning on / off one of the four loads (depending on the number of claps) - also controls any lighting effects machine. Most automatic lighting effects use a master oscillator, the frequency of which is controlled by a variable resistor. Therefore, either the speed of switching lamps or garlands does not match the tempo of the music, or you have to manually reconfigure the generator for each melody. This acoustic switch allows you to switch the garlands in accordance with the tempo of the music. In the absence of music or in pauses, the garlands switch with a minimum frequency, which is set by selecting the resistor R19.

I used this acoustic switch in tandem with the K556RT4 PROM [1] lighting effects machine in one case, using the 4th channel relay to turn it on (+5V - circuit power, -220V - garland power). The sensitivity of the switch is adjusted by the trimming resistor R8, so that it reacts to music, but does not switch the switching channels of the loads. Practice shows that in addition to the 4th channel involved, it is enough to use the 2nd and 3rd channels, and you should refrain from using the 1st channel, since it may be triggered by sudden bursts of music.

Consider the operation of the switch. From the VM1 microphone, through the tuning resistor R8, the signal is fed to the input of the limiting amplifier on the K538UN1 chip. After amplification, the signal is detected by the diodes VD5, VD6 and fed to the base of the transistor VT1. Its collector load includes a resistor optocoupler OEP-13, which controls the generator of the automatic lighting effects. Thus, transistor VT1 opens with a burst of the noise spectrum of the melody, and the output impedance of the optocoupler (pins 2 and 4) decreases, which leads to an increase in the speed of switching garlands. In this case, the transistor VT1 does not open completely (the degree of opening is regulated by resistor R8 so that the load switch does not work).

(click to enlarge)

With a sufficiently strong pop, VT1 opens completely, the first waiting multivibrator on the elements DD3.2 and DD3.3 is launched at a low level, which works as a delay for a time t, determined by the elements R3 and C2. With the ratings R3 and C2 indicated on the diagram, t = 0,3 s. The delay is necessary to prevent false operation of the decimal counter DD1 (counting more than one pulse). A low level from the collector VT1 simultaneously passes to the input of the counter DD1. The second multivibrator lengthens the input pulse at R=2,2 MΩ and C1=1 uF by about 4 s. This is the time during which the number of claps is counted by the DD1 counter and there is a ban on reading information from it by the DD2 chip.

For example, you made three claps. The counter DD1 gave a positive level at the output D3. At the end of 4 s, a high level is set at the control input of the DD2 chip, which allows the transfer of a logical "1" from the OT input to the D3 output. This level trigger DD4.2 flips to the opposite state. Key VT3 controls relay K2, which switches the load N2. At the same time, a high level from the output D3 of the DD2 chip through the VD3 diode resets the counter DD1. LED VD10 signals the inclusion of the corresponding load. Chain R6, C3 sets all triggers to zero when the device is turned on.

Block A1 can be used separately to control only the lighting effect machine. If this is not necessary, then instead of the VS1 optocoupler, a constant resistor with a resistance of 1 kOhm is included in the VT10 collector.

Literature

To help the radio amateur, 1990, No. 108.

Author: A. Sataev, Zarechny, Sverdlovsk region; Publication: N. Bolshakov, rf.atnn.ru

See other articles Section Clocks, timers, relays, load switches.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Machine for thinning flowers in gardens 02.05.2024

In modern agriculture, technological progress is developing aimed at increasing the efficiency of plant care processes. The innovative Florix flower thinning machine was presented in Italy, designed to optimize the harvesting stage. This tool is equipped with mobile arms, allowing it to be easily adapted to the needs of the garden. The operator can adjust the speed of the thin wires by controlling them from the tractor cab using a joystick. This approach significantly increases the efficiency of the flower thinning process, providing the possibility of individual adjustment to the specific conditions of the garden, as well as the variety and type of fruit grown in it. After testing the Florix machine for two years on various types of fruit, the results were very encouraging. Farmers such as Filiberto Montanari, who has used a Florix machine for several years, have reported a significant reduction in the time and labor required to thin flowers. ... >>

Advanced Infrared Microscope 02.05.2024

Microscopes play an important role in scientific research, allowing scientists to delve into structures and processes invisible to the eye. However, various microscopy methods have their limitations, and among them was the limitation of resolution when using the infrared range. But the latest achievements of Japanese researchers from the University of Tokyo open up new prospects for studying the microworld. Scientists from the University of Tokyo have unveiled a new microscope that will revolutionize the capabilities of infrared microscopy. This advanced instrument allows you to see the internal structures of living bacteria with amazing clarity on the nanometer scale. Typically, mid-infrared microscopes are limited by low resolution, but the latest development from Japanese researchers overcomes these limitations. According to scientists, the developed microscope allows creating images with a resolution of up to 120 nanometers, which is 30 times higher than the resolution of traditional microscopes. ... >>

Air trap for insects 01.05.2024

Agriculture is one of the key sectors of the economy, and pest control is an integral part of this process. A team of scientists from the Indian Council of Agricultural Research-Central Potato Research Institute (ICAR-CPRI), Shimla, has come up with an innovative solution to this problem - a wind-powered insect air trap. This device addresses the shortcomings of traditional pest control methods by providing real-time insect population data. The trap is powered entirely by wind energy, making it an environmentally friendly solution that requires no power. Its unique design allows monitoring of both harmful and beneficial insects, providing a complete overview of the population in any agricultural area. “By assessing target pests at the right time, we can take necessary measures to control both pests and diseases,” says Kapil ... >>

Random news from the Archive

Recycling plastic into fuel 22.01.2019

Scientists from Purdue University (West Lafayette, USA) have developed a new method for converting plastic, which involves obtaining clean fuels, polymers and monomers.

The developers called the new method hydrothermal liquefaction. It lies in the fact that polymers melted at high temperature are combined with supercritical water (a transition state between liquid and gaseous forms of water).

As a result, the process of formation of a substance called naphtha occurs. Oil has combustible properties and can be converted into fuel or separated into other components. Such developments of scientists were prompted by the fact that every year the amount of plastic in the oceans is increasing.

According to experts, the amount of plastic waste that enters the world's waters reaches from 8 to 12 million tons annually. This negatively affects representatives of the oceanic and marine fauna. Even whole "garbage islands" are formed. Also, the new method can save the planet from fuel shortages and improve the global environmental situation.

Other interesting news:

▪ oily water

▪ Your own windmill on the roof

▪ Automation against pirates

▪ Eternal flash memory

▪ Super strong carbon nanotube film

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Videotechnique. Article selection

▪ article by Vesalius Andreas. Biography of a scientist

▪ article How do Arabs write and read numbers? Detailed answer

▪ article Operator of a self-propelled roller with smooth rollers. Standard instruction on labor protection

▪ article Power supplies with a capacitor voltage divider. Encyclopedia of radio electronics and electrical engineering

▪ article Picky magnetic goose. physical experiment

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews