A simple amplifier on a K174XA10 chip. Scheme, description

Free technical library

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

A simple amplifier on a K174XA10 chip. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Transistor power amplifiers

Comments on the article

Gone are the days when radio amateurs, as one of the first designs, assembled tube audio frequency amplifiers (UZCH). Bulky output and power transformers determined the final weight and dimensions of the device, high levels of supply voltages, required the use of high-voltage smoothing capacitors in the anode and screen power filters, and created a risk of electric shock. A significant lamp filament current was also required, which reduced the efficiency of the amplifier and created additional (unjustified) heating. To bring to a state of readiness after switching on, it took some time (to warm up the cathodes of the lamps) or it was necessary to keep the cathodes of the lamps heated.

Let us pay tribute to the lamps and note that transistor and integrated ultrasonic frequencies are free from all of the listed shortcomings. But some transistor amplifiers are superior in manufacturing complexity to tube ones, and integrated ones require a large number of additional "attached" elements, which negates their advantages from the use of microcircuits.

But nothing stands still, and, in my opinion, the last difficulty has also been overcome. True, such a convenient circuit suddenly turned out to be part of a more complex combined analog integrated circuit (IC) K174XA10, although it would be useful to have such a "chip" separately.

As can be seen from the circuit diagram (see figure), UZCH contains a minimum of details and can be very widely used. The advantage of this IC is also the prospect for a novice radio amateur, after "running in" the UZCH and studying the capabilities of the IC [1,2], to assemble an AM receiver on the same chip, and then a combined one - AM-FM.

A simple amplifier on a K174XA10 chip

Imagine a typical everyday picture: after connecting the Dandy game console to the TV (as usual - with one cord to the antenna jack) and turning on the power of the console, the neighbors suddenly begin to behave like children - knock on walls, on batteries, come as uninvited guests to express their attitude towards you for the interference that appeared on their TVs! The mood for the game, as a rule, then deteriorates greatly. But many TVs have a "video input", and "Dandy" has a video output, they need to be connected to each other, but at the same time, with a high-quality "picture" on the TV screen, the game becomes "dumb". To return the "voice", you need to connect the "Dandy" output to the UZCH input of the TV, but this, as a rule, is not there and you need to "climb" into the TV. To avoid this, you can make the proposed UZCH, connect it to the AF output of the set-top box - and the problem is solved.

The input signal of the AF, having passed the isolation (DC) capacitor C1, is fed to the volume control R1, and from its engine to the input of the IC, is amplified by it and through the isolation capacitor C4 is fed to the loudspeaker (dynamic head) VA1. The amplification of the IC depends on the capacitance of the capacitor C3, it is not recommended to greatly reduce it. C2 provides decoupling of the UZCH cascades (inside the IC) for power, and also contributes to the stability of the UZCH when powered by discharged batteries. C5 and C6 increase the resistance of the amplifier to self-excitation, and C5 also affects the frequency response. UZCH. C5 and C6 are optional and are installed only when necessary. Oxide capacitors can be used of any brand, the resistor R1 of the volume control - if possible, group B, which provides smoother adjustment of the sound level. Dynamic head BA1 - any type with a resistance of 8 ... 16 ohms, it is important that the connecting wires be as short as possible, since with long wires, part of the output power is lost on them, since these wires are part of the UZCH load resistance.

The amplifier can serve as a separate unit wherever it is necessary to raise the level of the AF signal for perception by the human ear: in a tape recorder, player, as part of various probes, loud-speaking toys, apartment calls, as an ultrasonic frequency converter for detector receivers, for example, in the country, etc. UZCH is not critical to the supply voltage and consumes a small current, but provides high-quality sound reproduction. Those who rely on more gain should use a higher supply voltage.

The author deliberately does not give the technical data of the amplifier: they fully correspond to those given in [1] and do not need comments.

References:

Microcircuits for household equipment/Handbook. - M. Radio and communication, 1989. - S.169-173.
Brodsky Yu. "Selga-309" - superheterodyne on one chip//Radio. - 1986. - No. 1. - P.43-45.

Author: V.Popov

See other articles Section Transistor power amplifiers.

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

Microrobots of Swiss watchmakers 15.01.2001

A group of employees of the Swiss Federal Institute of Technology led by Roland Siegart created a group of microrobots. The size of each of them is slightly larger than a cube of refined sugar.

The robot is driven by two battery-powered stepper clock motors. Four infrared sensors allow him to bypass obstacles and follow the corridors of the labyrinth. When two robots meet, they exchange their serial numbers via infrared communication, and the one with the higher number (that is, he is "younger") gives way to the "older" one and can, obeying his commands, follow him.

Microrobots are able to report their movements to the central computer by radio. And he builds a map of the premises they are examining. So it is proposed to use a team of robots for reconnaissance, say, of premises at a nuclear power plant after a release of radioactivity.

Other interesting news:

▪ stone age dentists

▪ E-bike with face recognition

▪ Odysseus didn't live in Ithaca

▪ Super glue will close wounds in the stomach and stop the leakage of acids in the plant

▪ There are more cell phones than toothbrushes

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

▪ Bluebeard article. Popular expression

▪ article What is mistletoe? Detailed answer

▪ article Stone-cutting circular saw. home workshop

▪ article Preparation of solid soap from drying and semi-drying vegetable oils. Simple recipes and tips

▪ article Spectators can't guess which hand the coin is in. Focus Secret

Leave your comment on this article:

All languages of this page

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