Manipulation without clicks. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Beginner radio amateur
Comments on the article
Radio amateurs often use sound signaling devices built on two generators in their designs - one of them operates at a frequency of about one hertz and controls the operation of the other, tone, the frequency of which is usually close to 1000 Hz (Fig. 1).
The disadvantage of such a signaling device is the appearance of clicks in the sound signal that occur when the tone generator is turned on and off. They are explained by the presence of a constant component in the bursts of tone generator pulses. These bursts (Fig. 2, a) can be represented as the sum of bipolar pulses with a frequency of 1000 Hz (Fig. 2, b) and pulses following at a frequency of 1 Hz (Fig. 2, c) - they create clearly audible clicks.
It's pretty easy to avoid them. It is enough to apply the output signal of the first generator to both elements of the second, and turn on the sound emitter between their outputs (Fig. 3). In this case, the output signal will not contain a component with a frequency of 1 Hz and clicks. In addition, the volume of the signal increases.
In such a device, the use of OR-NOT microcircuits is undesirable, since their switching threshold is below half the supply voltage, the generated pulses are asymmetrical, and clicks remain at the generator output, although less noticeable.
If the device already has signals with the required frequency and you only need to control one signal with the help of another, it is enough to use a node made on two elements (Fig. 4). Both AND-NOT (K561LA7) and OR-NOT (K561LE5) microcircuits are suitable here.
In the case of an asymmetric tone signal, when the pause duration is significantly longer than the pulse duration, after passing through the elements of the node, a noticeable component with the manipulation frequency will remain in it. In this case, control with a JK or D trigger will help (Fig. 5).
When a high logic level is applied to the inputs R and S, both trigger outputs are also high, when a low level is applied, anti-phase symmetrical tones with a frequency twice as low as the input, and, of course, without a component with a frequency of 1 Hz.
Author: P.Aleshin, Moscow
See other articles Section Beginner radio amateur.
Read and write useful comments on this article.
<< Back
Latest news of science and technology, new electronics:
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 ... >>
Wireless speaker Samsung Music Frame HW-LS60D
06.05.2024
In the world of modern audio technology, manufacturers strive not only for impeccable sound quality, but also for combining functionality with aesthetics. One of the latest innovative steps in this direction is the new Samsung Music Frame HW-LS60D wireless speaker system, presented at the 2024 World of Samsung event. The Samsung HW-LS60D is more than just a speaker system, it's the art of frame-style sound. The combination of a 6-speaker system with Dolby Atmos support and a stylish photo frame design makes this product the perfect addition to any interior. The new Samsung Music Frame features advanced technologies including Adaptive Audio that delivers clear dialogue at any volume level, and automatic room optimization for rich audio reproduction. With support for Spotify, Tidal Hi-Fi and Bluetooth 5.2 connections, as well as smart assistant integration, this speaker is ready to satisfy your ... >>
A New Way to Control and Manipulate Optical Signals
05.05.2024
The modern world of science and technology is developing rapidly, and every day new methods and technologies appear that open up new prospects for us in various fields. One such innovation is the development by German scientists of a new way to control optical signals, which could lead to significant progress in the field of photonics. Recent research has allowed German scientists to create a tunable waveplate inside a fused silica waveguide. This method, based on the use of a liquid crystal layer, allows one to effectively change the polarization of light passing through a waveguide. This technological breakthrough opens up new prospects for the development of compact and efficient photonic devices capable of processing large volumes of data. The electro-optical control of polarization provided by the new method could provide the basis for a new class of integrated photonic devices. This opens up great opportunities for ... >>
| Random news from the Archive Air conditioning system that does not require electricity
14.09.2017
Researchers at Stanford University have developed a high-tech optical surface that creates an air conditioning system that requires almost no electrical energy to operate. Water is used as a heat carrier in this system, which passes through heat exchangers placed under the optical surface. These surfaces, due to the structure of the surface, reflect more than 97 percent of the energy of the sun's rays falling on them, while dissipating the thermal energy carried by water into the environment. And this approach allows you to drastically reduce the amount of energy required for air conditioning the interior of buildings.
Tests carried out on the "passive cooling" system have shown that the water in this system can be cooled to a temperature of 3-5 degrees Celsius below ambient temperature. Based on the collected experimental data, the Stanford researchers created a mathematical model of a refrigerated building located in a place with a dry and hot climate, similar to the climate in the Las Vegas area. Energy savings due to the use of the passive cooling system amounted to 14.3 MWh during one summer month, which corresponds to a 21 percent saving of the total amount of energy spent on air conditioning.
According to available data, cooling and air conditioning consumes about 15 percent of the electricity generated worldwide, and by 2050, the total amount of energy spent on air conditioning will increase another 10 times. Therefore, even a 20 percent energy saving will save huge amounts of money and significantly reduce the amount of greenhouse gases emitted into the atmosphere.
Researchers at Stanford University have now founded a new company called SkyCool Systems to further develop and commercialize passive cooling technology. The new system will be developed with an eye to its easy integration into existing air conditioning systems of various types and manufacturers, including data center cooling systems, where energy savings play a major role.
|
Other interesting news:
▪ Opioid pain reliever without side effects
▪ A chamber the size of a grain of salt
▪ The energy of an electron entering water was measured
▪ Liquid crystal fabric changes shape when heated
▪ World's largest electric skyscraper to be built
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ site section Batteries, chargers. Article selection
▪ article by Friedrich Nietzsche. Famous aphorisms
▪ article What is the difference between fruits and vegetables? Detailed answer
▪ article Web designer of the Internet marketing department. Job description
▪ article Electrician's tool. Directory
▪ article Card frame on a magic wand. Focus Secret
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