Converter for satellite TV reception. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Телевидение
Comments on the article
The design of this device was published in the magazine "Radio Television Electronics" (Bulgaria) N 10,11 for 1986.
(click to enlarge)
Design
The irradiator, which is a cavity resonator, is machined from metal. Its dimensions depend on the received frequency. Diodes (shown in red) - AA703A (diameter 3,8 mm). The converter is tuned by setting the maximum current using a trimmer resistor.
The location of the parabola and irradiator
The diameter of the parabolic mirror is not critical (the larger, the more sensitive). The mixer is installed at the focus of the parabola.
What is a "trap" and what it is made of - I do not know.
Author: Nikolai Bolshakov
Design - a two-chamber frequency converter made in a round waveguide (inner diameter 8 mm. I have doubts, probably it should be 18 mm.), The trap is a conventional feed for a round waveguide, its dimensions will depend on the parameters of the main mirror. You can make the irradiator from aluminum.
The parameters are approximately as follows: the range is 10.7-11.3 GHz, the noise is at least 7 dB (that is, rather mediocre). The frequency stability will probably also be low, because. the design of the local oscillator is designed to adjust the frequency by changing the supply voltage AA703. It is strange why there is a 100 μA microammeter in the local oscillator power circuit when the supply current reaches 300 mA?
Judging by the year of publication of the article (1986), this design appeared at the "dawn" of the development of satellite TV reception, and cannot have very good characteristics. Its use may be expedient only for microwave experiments in the 10 GHz band.
Author: Svyatoslav Silakov, Publication: N. Bolshakov, rf.atnn.ru
See other articles Section Телевидение.
Read and write useful comments on this article.
<< Back
Latest news of science and technology, new electronics:
Alcohol content of warm beer
07.05.2024
Beer, as one of the most common alcoholic drinks, has its own unique taste, which can change depending on the temperature of consumption. A new study by an international team of scientists has found that beer temperature has a significant impact on the perception of alcoholic taste. The study, led by materials scientist Lei Jiang, found that at different temperatures, ethanol and water molecules form different types of clusters, which affects the perception of alcoholic taste. At low temperatures, more pyramid-like clusters form, which reduces the pungency of the "ethanol" taste and makes the drink taste less alcoholic. On the contrary, as the temperature increases, the clusters become more chain-like, resulting in a more pronounced alcoholic taste. This explains why the taste of some alcoholic drinks, such as baijiu, can change depending on temperature. The data obtained opens up new prospects for beverage manufacturers, ... >>
Major risk factor for gambling addiction
07.05.2024
Computer games are becoming an increasingly popular form of entertainment among teenagers, but the associated risk of gaming addiction remains a significant problem. American scientists conducted a study to determine the main factors contributing to this addiction and offer recommendations for its prevention. Over the course of six years, 385 teenagers were followed to find out what factors may predispose them to gambling addiction. The results showed that 90% of study participants were not at risk of addiction, while 10% became gambling addicts. It turned out that the key factor in the onset of gambling addiction is a low level of prosocial behavior. Teenagers with a low level of prosocial behavior do not show interest in the help and support of others, which can lead to a loss of contact with the real world and a deepening dependence on virtual reality offered by computer games. Based on these results, scientists ... >>
Traffic noise delays the growth of chicks
06.05.2024
The sounds that surround us in modern cities are becoming increasingly piercing. However, few people think about how this noise affects the animal world, especially such delicate creatures as chicks that have not yet hatched from their eggs. Recent research is shedding light on this issue, indicating serious consequences for their development and survival. Scientists have found that exposure of zebra diamondback chicks to traffic noise can cause serious disruption to their development. Experiments have shown that noise pollution can significantly delay their hatching, and those chicks that do emerge face a number of health-promoting problems. The researchers also found that the negative effects of noise pollution extend into the adult birds. Reduced chances of reproduction and decreased fertility indicate the long-term effects that traffic noise has on wildlife. The study results highlight the need ... >>
| Random news from the Archive Toshiba Dynabook R82 and Dynabook RT82 hybrid tablets
11.03.2015
Toshiba has expanded its range with two similar devices: Dynabook R82 and Dynabook RT82 hybrid tablets running Windows 8.1. The devices are similar in appearance and both received Intel Core M processors.
The RT82 model, which is aimed at the corporate segment, will be available in configurations with CPU Core M 5Y31, Core M 5Y51 and Core M 5Y71. Dynabook R82, in turn, judging by the site, will receive only the youngest of these solutions. The devices are equipped with Full HD screens with a diagonal of 12,5 inches. RAM is provided 2, 4 or 8 GB, depending on the modification. For data storage, there is an SSD with a capacity of 128 or 256 GB.
For their size, the tablets are quite light - about 700 g without a keyboard docking station. With it, the mass rises to 1,4 kg. Dimensions are 309 x 200 x 8,8 mm. At the moment, the description of new products is only on the official website, which is in Japanese. For this reason, it is quite difficult to deal with all the characteristics. It is known for certain that the RT82 modification is equipped with a TPM module.
The tablets also feature 802.11ac Wi-Fi, Bluetooth 4.0, 2MP and 5MP cameras, and Micro USB 2.0 and Micro HDMI ports. You can also find USB 3.0 and Ethernet connectors on the docking station. The cost of the Dynabook RT82 model will be about $1700.
|
Other interesting news:
▪ Integration of electric vehicles with the home power system
▪ JUICE space probe
▪ Flying over Venus
▪ Electricity storage in bricks
▪ Flexible Samsung Smartphone
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the Electrician website. PUE. Article selection
▪ article Kovalevskaya Sofia Vasilievna. Famous aphorisms
▪ article What color noises, besides white noise, exist? Detailed answer
▪ article Indoor fountain. Children's Science Lab
▪ article Antenna rotator. Encyclopedia of radio electronics and electrical engineering
▪ article A simple voltage regulator on a 142EN1G chip, 9/5 volts 0,5 amperes. 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