Encyclopedia of radio electronics and electrical engineering / radio reception
Comments on the article
The K174XA10 integrated circuit contains a radio frequency amplifier, a local oscillator, a mixer, an intermediate frequency amplifier, a detector, a low frequency amplifier, and a supply voltage stabilizer. Using this chip, you can easily assemble a compact superheterodyne, but the proposed device is a direct amplification receiver. Therefore, the radio frequency amplifier, local oscillator and mixer included in the microcircuit are not used here, and the intermediate frequency amplifier performs the functions of a radio signal amplifier.
The receiver is designed to receive signals in the range of long or medium waves with a battery voltage of 4,5 V and consumes about 10 mA in silent mode or 35 mA at medium volume. The rated output power is 100 mW.
The circuit diagram of the receiver is shown in the figure.
The oscillatory circuit of the magnetic antenna L1, C1 emits a signal whose frequency is equal to the resonant frequency of the circuit, and from the coupling coil L2 through the capacitor C2 it enters the input of the radio frequency amplifier - output 2 of the microcircuit. In it, the signal is amplified and detected. The detected low-frequency signal from pin 8 of the microcircuit is fed through C8 and R4 to the volume control R5, and from it to the input of the audio frequency amplifier (pin 9 of the microcircuit). Capacitors C7 and C11 eliminate the high frequency component of the detected voltage. From the output of the audio frequency amplifier (pin 12) through the capacitor SU, the sound signal is fed to the dynamic head BA1. The XS1 jack is for connecting headphones. This automatically turns off the dynamic head. The remaining elements provide the chip mode.
All parts of the receiver are located on a printed circuit board made of one-sided foil fiberglass, shown in the figure.
As a capacitor C1, you can use a small-sized two-section assembly of capacitors of variable capacitance from the Selga radio receiver, connecting both sections in parallel.
The magnetic antenna is made on a 400NN grade ferrite rod with a diameter of 8 and a length of 65 mm. For the long wave range, the L1 coil should have 160 turns of PEV-1 wire with a diameter of 0,1 mm. Winding is carried out in bulk with 40 turns in each of 4 sections. Coil L2 - 7 turns of PEV-1 wire with a diameter of 0,2 mm. For the medium wave range, the L1 coil is 70 turns of LESHO litz wire 10x0,07 turn to turn in one layer, and L2 is the same as for long waves.
See other articles Section radio reception.
Read and write useful comments on this article.
<< Back
<< Back
Latest news of science and technology, new electronics:
Artificial leather for touch emulation
15.04.2024
In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>
Petgugu Global cat litter
15.04.2024
Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>
The attractiveness of caring men
14.04.2024
The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>
| Random news from the Archive To the hospital - no tie
02.01.2005
A medical student who practiced at a large New York hospital noticed that a doctor's hanging tie, when examining a patient lying on a bed, sometimes touches the patient.
The student became interested: could the ties of doctors (American doctors believe that one should be “at the parade” at work in order to inspire more confidence in patients) serve as carriers of nosocomial infections?
Microbiological analysis of 42 ties of doctors and assistants showed that 20 of them had dangerous microorganisms on the surface, including Staphylococcus aureus, the causative agents of pneumonia. For control, they took 10 ties from the hospital guards - only one turned out to be contaminated with germs.
The transmission of diseases through a tie is unlikely, but for patient safety it is best when the doctor is dressed in a gown that is tightly buttoned under the chin, the author of the study concluded.
|
Other interesting news:
▪ prominence model
▪ The composition of the intestinal microflora
▪ Alien star discovered in the Milky Way
▪ Laziness is a sign of high IQ
▪ Washing machine Siemens iQ700
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the Electrician website. PUE. Article selection
▪ article Let the assassins start first. Popular expression
▪ article How much does the weight of a body at the Earth's equator differ from the weight of the same body at the poles? Detailed answer
▪ Article Simple knot. Travel Tips
▪ article Heat-resistant alloys for heating devices. Encyclopedia of radio electronics and electrical engineering
▪ article Car power supply for a laptop, 12/19 volts 3 amps. 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
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese