Sabtu, 16 Februari 2013

modulation radio receiver

Judging from the type of modulation radio receiver that is divided into two kinds of AM radio when the modulation amplitude modulation is used which has the nature of the modulated signal amplitude varies with variation in the signal amplitude information. The second type of radio receiver is an FM radio if the modulation frequency modulation is used, the frequency of the modulated signal varies with the signal amplitude variations information. Radio frequency carrier amplitude modulation (AM) in the range of 535 to 1605 kHz. Carrier frequency of 540 kHz to 1600 characterized by intervals of 10 kHz. FM radio has a band of 88 to 108 MHz between television channels 6 and 7 VHF. FM stations are marked with a flashlight at 200 kHz frequency separation starts at 88.1 MHz for a maximum of 100 stations. FM station has a maximum deviation of 75 kHz from 25 kHz frequency flashlights upper and lower "guide lines" to minimize interaction with the frequency band setting. Understanding information is transmitted from the AM radio station AM radio, electrically sound image (taken from a microphone or any other program sources) are used to modulate the amplitude of a carrier wave is then transmitted from the transmitting antenna radio station. This contrasts with the FM radio signal which is used for the modulation of the carrier frequency. The spectrum of frequencies between 535 kHz and 1605 kHz and the carrier wave are separated by 10 kHz. Radio receiver can tune to receive one of a number of radio carrier frequency in the reception area. This makes it practical to move the signal from the carrier frequency of the radio medium in the process now where the heterodyne. Hetero-dyne receiver, most electronically maintain Mene-middle frequency setting that's just a fraction of As with receiver circuit must be set when the station changed. Heterodyne Heterodyne Principle Radio is broadcast signal transfer method from a local carrier at intermediate frequencies specified in the receiver so that the receiver does not have many set back when the channel changed. Interference of two waves will produce a frequency kites and this technique provides the radio settings to force a particular radio frequency generating kites called intermediate frequency or IF abbreviated. Elektromanetik carrier wave that carries the signal with the help of amplitude modulation or frequency modulation of the carrier signal can move in different frequency by a process called heterodyning. The move was met with mixed carrier modulated with a different frequency of a sine wave. This process produces kites frequency equal to the difference between frequencies. Mixing the beats coming from the carrier frequency and the local oscillator produces intermediate frequency (IF), the amount fixed. Most radio receivers can be constructed to use the radio signal that much. Local oscillator frequency is set to produce the same beats with fixed frequency IF. By heterodyning system with just one radio receiver, can be set for reception of local radio stations anywhere, but if it does not use heterodyning would require a radio receiver for each transmitter station. Radio Signal Radio communication is generally in the form of transmission of AM or FM radio. Single broadcast signal, thus a monophonic audio signal, can be done with direct amplitude modulation or frequency modulation. Provides a more complex transmission lines that emerge from the sum and difference frequencies resulting superposition of multiple carrier wave signal. For example in stereo FM transmission, the number of left and right channels (L + R) is used for frequency modulation of the carrier and separate sub-carrier at 38 kHz is also superimposed on the carrier. Sub-carrier is modulated with the difference signal (LR) so ditransimisikan signal into separate left and right to produce stereo at diplayback. In television transmission, the three signals must be sent to the carrier, namely audio, image intensity and chrominance images. This process uses two sub-carriers. Other transmissions such as satellite TV and telephone transmission distance using a lot of sub-carriers to transmit multiple signals simultaneously. AM radio uses electricity picture of a sound source with an amplitude modulated carrier wave. At the end of the receiver in the detection process this image released back of the carrier and tuned back into sound by loudspeakers.
READ MORE - modulation radio receiver

electronic circuits


READ MORE - electronic circuits

First time TV service

First time TV service
Electronic Components is the smallest part of an electronic circuit, or electronic components can be said to be the elements that make up an electronic circuit. If the electronic circuits that have a specific function are collected and form an electronic system, the electronic system is called a plane, for example: Aircraft Television formed from a collection of circuits that has a function as a tuner, IF, AGC, etc.. Electronic components that make up a television receiver, and there are a variety of different types, here the components are grouped by type for easy to search. Each component is discussed and described in detail, where any discussion of how characteristics include, among others, what basic ingredients, how the physical form and how the schematic drawing, how to find persamaanya if you can not find the same components etc, besides every ahir description is also shown what damage possible and often happens on these components, so it can help in the repair process. The components that make up a television set, among others: Passive components Resistors, Variable Resistor, Capacitor Active components Diodes, Transistors, ICs Inductor / Transformer Inductor, Transformer, Coil, Degausing Coil, Yoke, Flyback Transformer Display Seven Segment, CRT, LCD, Plasma Display Special component Relay, Opto Coupler, Cristal, Cristal Filter, Saw Filter, Delay Line Television is a broadcast tentacle picture. Word comes from the word tele television and vision; away with their respective sense (tele) and visible (vision). So mean visual or television can be seen from a distance. Findings television wheels aligned with the findings, because these findings could change the world civilization. Beginning from television of course can not be separated from the discovery of policy, law of electromagnetic waves discovered by Joseph Henry and Michael Faraday (1831) which is the beginning of the era of electronic communication. Then a row found cathode ray tube (CRT), the black and white television and color television system. Certainly the development of knowledge will continue to grow especially with the discovery of the LCD, which makes the TV in this day and age getting thinner with the photos that are not less good thing with the TV tube.

So at this time we should know very well about the TV system because almost all households have good black and white TV or a color. the types of damage and I know the damage:

Good Tips Techniques Basic Service TV BASIC AND ANALYSIS TECHNIQUES AND HOW TO FIX IT Here is a basic technique to analyze how the damage to the television: -The types of damage and I know the damage: 1. Totally dead. if the television suddenly dies, the first thing to do is: a. open smua existing couplers. b. see if the fuse / fuse broken, if broken try to replace with the same size trus ampere turn on. if the fuse broke again means local power supply is defective. The fix: Try measuring the besar.ukurannya elco 100uf/400v.ukur usually alternating avometer use a scale of 10 ohm.jika both disconnected likely broken diode or transistor. - Try test / measuring diodes that are near the switch on / off, there are 4 pieces . use avometer on a scale of 10 ohm.ukur alternating balik.jika rusak.ganti connect with both mean the same size. - Try measuring transistor large, footed tiga.ukur leg number 2 and 3 alternating use a scale of 10 ohm.jika avometer means rusak.ganti connect both with the same number. - If the measured elco already disconnected mean suply already bagus.coba turn on again - If still want Flash ndak try measuring the existing horizontal transistors deket plyback.caranya replace damaged diatas.jika equal with the number who tried to turn on lagi.insyaallh tv sama.trus can dah flame. Search Procedures Damage Efficiency measures required in the repair procedure is as follows.

1) The state of disorder known When receiving a TV that would be serviced, listen / check damage from consumer to facilitate easy inspection.

2) Estimate of Damaged Block The TV is turned on, set the controls noise, contrast, brightness and color. See symptoms appear on the TV screen for guessing which part is damaged. Make appropriate estimates of damaged block table damage.

3) Divide A Damaged Blocks Despite a series of suspicious has been determined, but the area being examined is extensive. Therefore, the more efficient the damaged part to be found if the area being examined more limited.

4) Find the section of Damaged After creating a suspected area more narrow, measuring voltage and resistance using Multitester. Block TV Color television system using three signals to work perfectly, the three signals are: • Signal sound carrier (FM) • picture carrier signal (AM) • Signal luminance (brightness) and chrominance signals synchronization (carrier color) In general, these signals are known as Signal Audio, Video Signal luminance (brightness) and chrominance signals Video (color), and thanks to the three signals allow us to see color images and hear sounds. The three signals are processed by different circuits, in which each series are grouped by function, but today most television is used in circuits that pack in an IC / Single chip that can hardly identify which parts of its part again unless we have a question or television schematic datasheets of Chip / IC is used. In addition to the three signal processing above, the television also has circuits horizontal deflection vetikal and useful for generating raster images on the tube, and - although it was not a major part of a television receiver - block remote-control circuit along controlnya also includes a series of very important the television generation. Here (in stages) discussed each function of blocks of color television sets where each block will be discussed in depth and detail, in addition to the discussion in ahir each block would show the symptoms if the block in question there is damage that will facilitate in the repair process. Below is shown a block diagram of PAL TV receiver. To go into further discussion you can right click on any image above or use the menu-in addition to the blocks or the link below Tuner RF amplifier, Mixer, Local Oscillator The series of Sound 5.5Mhz detector, Sound IF amplifier, FM detector, amplifier noise Circuit of Figure Picture IF amplifier, Video detector, AFT, AGC, Upholstery Video, Delay Line The series of Color Reproduction Amplifier Band-Pass, Element 1H delay, adder circuit-Deduction, phase switching circuit 180, Upholstery burs, Oscillator 4.43Mhz, UV amplifier, demodulator Synchronization circuit Toll Sync Separator, vertical pulse circuits, pulse circuits Horizontal Deflection Yoke Flyback Transformer Flyback transformer CRT tube Delta Type, Type In-Line, In-Line Type Trinitron The series of Power Supply Rectifier, regulator The type of Television Receivers Basically, television receiver system was divided into two, namely: Television black and white In black and white television images can not be viewed in accordance with the original color. Anything that looks dilayar glass looks just black and white. It is very different with color television, color picture that is displayed on screen will look similar to the originals. Color television picture we see on the television screen is a result of production from a camera. Object snapshot camera lens will be separated into three basic colors, namely red (R = red), green (G = green), and blue (B = blue). This separation results will be transmitted by television transmitter. Color TV transmitters emit signals: Audio (voice) Luminansi (image brightness) Krominansi (color) Sync (vertical / horizontal) Burst In color television receiver, all natural colors that have been separated into basic colors R (red), G (green), and B (blue) will be added back to the network color matrix to produce luminance signal Y and two signal krominansi, that V and U according to the following equation: Y = G+ 0.11BV +0.59 +0.30 R = 0.877 (R - Y) U = 0.493 (B-Y) In addition to pictures, television transmitters also carry voice signals are transmitted together with the picture signal in frequency modulation (FM) to avoid noise (noise) and interference. To transmit this signal, the transmitter and receiver must have the same color and sound. The system would have to follow a global standard and. In the picture there are several delivery systems, including: NTSC, PAL and SECAM.
READ MORE - First time TV service