Power supply of low-voltage radio equipment from the network. Scheme, description

Free technical library

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

Power supply of low-voltage radio equipment from the network. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Power Supplies

Comments on the article

Modern portable and pocket radios, especially imported ones, as a rule, are powered by two batteries or accumulators and can be powered under stationary conditions from any source with a stabilized voltage of 3 V and a permissible current of up to 0,2 A. The same voltage is also necessary for powering electronic games such as "Just WAIT" and many other devices. The necessary power supply, if you try, can be found in commercial stores, but imported and at an unreasonably high price, and the domestic industry produces few such power supplies. In addition, they usually do not have output voltage stabilization, which leads to listening to the network background.

Power supply of low-voltage radio equipment from the network
Fig. 5.1

Collecting the necessary source is within the power of anyone who knows how to use a soldering iron, and this will not require much time and high costs.

Here are two options for building such a scheme, assembled on different elements, and you can choose the specific one yourself, having become acquainted with their features and based on your capabilities.

On fig. 5.1 shows a simple circuit of a 3 V power supply (load current 200 mA) with automatic electronic overload protection (Iz \u250d 8 mA). The level of output voltage ripple does not exceed XNUMX mV.

For normal operation of the stabilizer, the voltage after the rectifier (on diodes VD1 ... VD4) can be from 4,5 to 10 V, but it is better if it is 5 ... 6 V - less source power is lost to heat dissipation by the transistor VT1 during operation stabilizer.

The circuit uses the HL1 LED and diodes VD5, VD6 as a reference voltage source. The LED is also an indicator of the operation of the power supply.

Transistor VT1 is mounted on a heat-dissipating plate. Transformer T1 can be purchased from any unified TN series, but it is better to use the smallest TI1-127/220-50 or TN2-127/220-50. Many other types of transformers with a secondary winding of 5 ... 6 V are also suitable. Capacitors C1 ... C3 type K50-35.

Power supply of low-voltage radio equipment from the network
Fig. 5.2

The second circuit (Fig. 5.2) uses the integral regulator DA1, but unlike the transistor regulator shown in fig. 5.1, for the normal operation of the microcircuit, it is necessary that the input voltage exceed the output voltage by at least 3,5 V. This reduces the efficiency of the stabilizer due to heat dissipation on the microcircuit - at a low output voltage, the power lost in the power supply will exceed that given to the load.

The required output voltage is set by the trimming resistor R2. The microcircuit is installed on the radiator.

The integral stabilizer provides a lower level of output voltage ripple (1 mV), and also allows the use of smaller capacitances.

Publication: cxem.net

See other articles Section Power Supplies.

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

Birds or insects 14.07.2008

The Swiss Institute of Ornithology has created a program for processing the reflected radar signal, which makes it possible to distinguish a swarm of insects from a flock of birds.

Insects do not pose a danger to aircraft, but bird strikes, most often occurring on approach to the airfield, annually cause global aviation losses of about $ 1,2 billion. An experienced air traffic controller can distinguish birds from insects on the radar screen, but this takes a few seconds.

Swiss ornithologists have compiled a collection of thousands of radar reflections from flocks of birds, insects and mixed flocks observed in the Sahara over Mauritania in 2003-2004. Their processing on a computer made it possible to develop a program that distinguishes insects from birds with an accuracy of 93-98%.

Other interesting news:

▪ Police robot car from Ford

▪ Technology for remanufacturing old engines

▪ New bonding material for batteries

▪ Parking and clean air

▪ New games will need an SSD

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site House, household plots, hobbies. Article selection

▪ article Developmental psychology. Lecture notes

▪ article Countries, peoples, languages. Big encyclopedia for children and adults

▪ article Elder racemosus. Legends, cultivation, methods of application

▪ article Unusual AM detector. Encyclopedia of radio electronics and electrical engineering

▪ article Scheme, pinout (wiring) cable Ericsson 8xx, 1018, T18. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

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