How to improve reception quality. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / radio reception
Comments on the article
Proposed at one time (see "Radio", 1985, N 12, p. 28) by A. Zakharov, a VHF radio receiver with a PLL is still repeated by many radio amateurs. And this is not surprising if we take into account such advantages as simplicity, absence of noise, and slight distortion of the low-frequency signal.
However, experience with this receiver revealed a significant dependence of the stability and quality of its reception on the length and position of the antenna and an insufficient synchronization bandwidth.
You can reduce the influence of the antenna by introducing a radio frequency amplifier (URCH) into the receiver. It is connected to the receiver as shown in the figure. To increase the synchronization bandwidth, the quality factor of the generator coil should be slightly worsened by winding it with a wire with a diameter of 0,28 ... 0,32 mm. With repeated repetition of the modified receiver, a significant improvement in the quality of reception was noted.
The generator used transistors KT306B (G) and KT3102B. the resistance of the load resistor in the collector foam should not go beyond 2,7 ... 3,6 kOhm, at a power supply voltage of +4 ... +6 V, the emitter current is 0.8 ... 1 mA.
Author: A. Sokolov; Publication: N. Bolshakov, rf.atnn.ru
See other articles Section radio reception.
Read and write useful comments on this article.
<< 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 Electromagnetic earthquake prediction
07.09.2002
Using a theory developed by Greek geophysicists, Japanese seismologists were able to detect the electrical and magnetic precursors of a major earthquake.
Greek scientists, working under the direction of Panagiotis Varotsos, have been claiming for about 20 years that the method they have developed makes it possible to capture changes in the Earth's electric and magnetic fields that appear several months before some earthquakes. The Greeks justify their theory by the fact that many rocks have a piezoelectric effect and, as mechanical stresses accumulate in them, they generate an electric field and related effects that can be registered.
Until now, other research teams could not confirm this hypothesis. And just recently, Japanese specialists from the Center for Research on Earthquake Prediction reported the registration of changes in the electric and magnetic fields on the Itsu Islands since March 2000.
Unusual changes intensified, and at the end of June of that year, a series of strong tremors broke out. However, according to many geophysicists, the hypothesis needs further testing.
|
Other interesting news:
▪ Dangerous smell of rain
▪ Viruses are 10 times stronger in the morning than in the evening
▪ The car should not drive silently
▪ Miniature robot transformer
▪ Digital 30A DC-DC Regulators IR38263/5
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ Telephony site section. Article selection
▪ article Medical physics. Crib
▪ article How long can the sun shine? Detailed answer
▪ article Work on sheet-fed offset printing presses such as HAMADA, RYOBI, YIYING, SPEEDMASTER, etc. Typical labor protection instructions
▪ article Why some microcontrollers are more reliable than others. Encyclopedia of radio electronics and electrical engineering
▪ article DC-to-AC converter. 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