Repair tips for beginners

Normally, to repair televisions need a circuit. to import, it is hard to find. Repair begins with (turn on the TV and the screen lights up?).

Frequent breakdown of all common TV (and our imports) there is – annular micro cracks in solder points, especially in the massive parts. (transformers, transistors on heatsinks, chip on radiators, or Blocks SLE tuners (in which the antenna is stuck).
This is because, that once when transporting the TV these details were shaking and ration their findings have microcracks. And in the process (High temperature in the television, temperature difference, air humidity) finally (a few years) increased the size of these cracks to complete loss of contact, and the cracks (ring microcracks in soldering locations) themselves oxidized due to long term.
I recommend the repair of any TV so if you do not solder, then at least carefully review the soldering massive parts. This can reduce the TV repair time is ridiculously.
If the TV does not turn on, and there is power in the socket, and the plug and cord serviceable network – then check the power button. At serviceable buttons – check the throttle filter in the power supply, after the diode bridge and the fuse which is usually located next to the power button or the diode bridge.
If the fuse is not necessary to change the fuse (they usually 4a) turn on the TV to the network without checking on the performance of the power unit. The fuse may burn out again, and a few of which thread parts. Instead of the fuse is soldered in the gap ordinary light bulb at 220V power from 40 …. 100 wool.
Pererezayem any track running to the diode bridge (reassignment). Turn on the TV to the mains. Light is on at full power, disable loop degaussing the picture tube. (You can vypayat thermistor degaussing) and turn on the TV to the network again.
If the light goes out – then run to the store and buy a new thermistor degaussing, taking a sample of the. Change it and everything will work. (This defect is common) If this is not the thermistor degaussing, then in case of discharge of 2 cotton 1k resistor …. 10to (I discharged a conventional light bulb at 220. And power 40 … 100 wool) electrolytic capacitor in the power supply (which accounts for the rectified mains voltage 310B.)
After closing its contacts dorazryadim tweezers – to complete zero, after keeping tweezers and about 20 seconds at the contacts. (YES THIS electrolytic capacitor discharge is necessary before each measurement on the resistance in the power supply). Tester to measure the voltage on this electrolyte after discharge, it should not exceed more than 0.5V. Toggle tester OM-METER mode and check the resistance of the electrolyte. It must be over 10, and anyone. If you are using a digital multimeter is necessary to check on the brink “diode test” or “squeaker probe” and other resistance annexes. I use a digital camera squeaker in such a case and simply check for a short circuit. If OM-meter shows that the electrolytic capacitor is closed, then you need to re-check the diode bridge (which stands on straightening network) cutting the plus path extending from the diode bridge to the electrolyte and power supply. Diodes in the bridge are checked separately (straight-poking at him to get here not vypaivaya (If you have a digital camera)). If the diodes in the bridge is operable solder track back cuts (stripping paint on her knife and deception and a piece of wire solders slashed place).
Next, check the chip (or transistor in the power supply). If a + with more electrolyte is on chip (transistor) in PSU circuit is shorted to a large negative electrolyte – we change all the chips in the power supply (and if there should transistor – then the transistor chip and also, what his) If there is no power supply ICs that change the transistor and another transistor which is energized at this powerful (large transistor). Also (in any TV repair, which is older than 3 years, you have to change all the small electrolytic capacitors in the power of the power supply) there is a large temperature and capacitors in the power supply do not last long.
On this often happens, pidsohshy that one of these little elektrolitikov makes burn key mikroszemu (transistor). And sometimes, IF NOT short-circuit the circuit 310B, (a network electrolyte e.g.) – the power supply may not start at all (Although all the details in it are OK) – due to the fact that elektrolitik a thread in the network chain (310in.) dried PSU. (This defect is very common). I should be all elektrolitiky, who stand in the high (net) of the power supply, besides the great. Replacing the matter, We check on soprativlenie network (the main electrolyte), (which has been short-circuited) – if he has not closed the network part of BP, all OK. But do not just include network. Suddenly, what thread you are not inspected and all you zamenyanie chips can be burned again.
We are doing so on: Cut the track going to one end of the diode bridge network (shifts) and soldered to the ordinary light bulb to break the power of 220V 40 …. 100 wool. If the lamp is lit at full power then we continue to look for damage to the power supply. And if the light bulb when the, He flashed for a moment, and is dimly lit or pulsing – all OK, repairs completed, unsolder bulb and propaivaem track, short cut slowness. If the fuse is intact and there is no short circuit on the circuit 310B to the electrolyte and a large voltage is applied to the power supply.
Replacing small elektrolitikov in the network part has given nothing. All details are correct. And the replacement of circuits in the power supply, too, did not bring anything. And the power supply did not want to run. the (often in our TVs “knight”) is that the power-generating small chip in the power supply is fed through a divider is assembled on one of the two resistors with cotton +310 volt (straight from the bridge and a large electrolyte) this makes the voltage from the divider 310 and to ( about 9 … 18In the. I do not remember). So I often happened, that kind of resistors are quite normal, and if they vypayat to check their resistance (which should be approximately 500k) their resistance is infinity =. me these 2 resistors and power supply should start. (It is also quite common).

It can still operate when the TV is turned on protection. You turn on the TV to the network and the light indicator starts to pulsate, or does not light up at all, But audible squeak with TV. In such cases, it may be 3 variant breakdown.

1) It is in the power supply from the old dried up small elektrolitiky. Because of them, the power supply voltage is started to give a greater than normal. And in some TV stands stabilizer to the output of the power supply, in some TVs voltage 29 In the (HR power chip), and in some (rarely) by 115 volts, are supplied to the power line scan (line transistor and TDKS). Interchanging elektrolitiky in the network of the power supply, you enter this PSU in the normal mode. Next, change the stabilizer which stands in the chain of 29 Article. (He about 40 Article. restrictions).
2) The second reason for tripping in the power supply is failure TDKS. He does 16 000 volts and often flies. Check TDKS breakdown (closing) You can include a tweeter tester mode between the common (furrow) TV cable and path that connects one end of a TDKSa (collector) the average output of more transistors on the heat sink near TDKSa. If a short circuit between these points is still there, it is necessary to unsolder or middle pin (collector) or slit track him. For, to separate the transistor from TDKSa and understand – What we punched (earthed) transistor or TDKS? Finding punched radioelement you change it. But sometimes, the transistor, and simultaneously burn TDKS, and it is better to change them both.
2a) sometimes so that a break in the line of the transistor capacitor, that goes from the collector, on housing. And thus the voltage at TDKS virostaet greatly leads to breakdown TDKSa and sometimes together with transistor. It is desirable vypayat this capacitor can welcome 1600 Article. and the higher the voltage and check for container. If there is nothing to measure capacity – you can replace it (from sin by further). Even if you are not at hand will be of such high-voltage capacitor, then the TV is turned on (and after replacing TDKS / or row transistor. So if you have this high voltage capacitor is defective TDKS voltage starts to crackle (sometimes even pop quite) – mean change you still have this high-Conder. And if all goes well, and the size of the image horizontally does not extend beyond the chapels – then the high-voltage capacitor is normal and does not need to change.
Always check that high voltage, coming to progressive scan (usually 115 … 118 In the. Less often 125 Article. – It depends on the size of the CRT and TV model) (the output of the power supply was normal). The power supplies typically trimmer which is exposed is the voltage. But it is always better to change elektrolitiky in the network portion of the PSU. Also boosted voltage higher than the norm can be seen in the image on the TV screen. If it eventually was operating horizontally more put – it means that the PSU voltage due to drying elektrolitikov in BP rose above the norm and these elektrolitiky time to change, until something flew out on the TV.
3) third tripping reason BP – is the closure of an electrolyte to the output of the power supply. Or the breakdown of a diode in the power supply unit toyzhe. It may also be stabilizing circuit chips (5In the, 9In the, 12In the) input, which is energized from power supply. This can be determined by turning the multimeter (saw) in ohmmeter mode or Tweeters, one probe on a common wire (housing) others run on the plus contact facing electrolytic capacitors at the output of the power supply. And if Kan any electrolyte circuit will then have to run on the track (from the PSU to the TV circuit) and try to find a punched part. Usually, this can be any stabilizer or stabilizing transistor. However, this option is rarely. Rather, the meeting point 1) and 2)
The horizontal bar in the middle of the screen

Is there sound, TV is, but there is no picture, rather white horizontal band in the middle of the screen.
Most often it is the failure of the personnel chip. It is usually close to the wires (connector) reaching in, rejects (coil). She always fixed on the radiator. warming Up TV 3-5 minutes you can touch all the chips radiators (sometimes it happens, the radiator HR cold chips). Most likely it flew personnel chip, and it should be replaced. But zhelatlnno run multimeter (tester), measure up to the total (Hull) wire, to all the contacts of personnel chips, and to look – whether there is any voltage at the terminals, there is 25 .. 29 in.? If the voltage 25 … 29 Article. there is, and chip radiator completely cold (can be very, very hot) – it means that it really is the chip. And you have to run to the store and buy a new chip.
If the voltage 25 … 29 Article. no chip on a frame, check all electrolytic capacitors alongside a well-TDKS, and diodes alongside a these electrolytes. There is created in some TVs, this voltage 25 … 29 Article.
But more often it makes the power supply voltage. And check electrolytes and diodes in the output of the power supply.
No sound, image has

It happens often fails speaker. Especially when the two speakers are connected in series. So burnt one speaker not pass through a signal to the other speaker.
We begin to repair the sound with the speakers continuity. Speaker should call on soprativlenie 8 ohm (rarely 4 ohm). After we check the quality of soldering wires to the speakers. Then go over the wire to the audio jack on the TV card (It can be a bad connector contact or mokrotreschiny in places of soldering the connector to the board (ring microcracks). Coming off of the connector go up the path to the sound chip (which is fixed to the heat sink). On the way along the paths to the conclusions of the sound chip (half of TVs) elektrolitichemkie are large capacitors around 470 … 1000 uF and voltage 16 … 40In the. What to check on the sample and drying tester, or stand parallel to the contacts are soldered, New electrolyte approximately the same capacity and voltage not less soldered, much (Attention! Do not reverse the polarity)
Sound chip on the heat sink and is subject to shaking when transpartirovke. So be sure to review its conclusions on the presence of microcracks in the brazing ring locations.
Next looping tester (with respect to ground) to all the contacts in the search for the sound chip supply voltage 12 … 27in one or several conclusions. If this (and none at all) the voltage on the findings no sound chip, check the output of the power supply (which creates 12 …. 27in voltage) and track power, coming from the block to the sound chip.
If the supply voltage 12 … 27in one or more sound chips conclusions, then we take in hand metallic object (Tweezers, otverku) holding the metal. And prikosatsya (very careful, but would not close the two contacts between an) all kontaktaktam sound chip at a time. And at the touch of one of your contacts will be sounded from the speakers loud AC hum. TV when this operation must be switched on :). And you are innocent prikosatsya another or the same hand, which hold the screwdriver to any metallic objects, Used by more than you have cited background applied to the input of the sound chip.
If the background of your prikosaniya the speakers pojavljatsja, and sound in TV programs is not – then you have to look for damage to the sound further, to the original sound chip. This chip can be another small sound chip, on which there is a signal from the video-audio inputs TV. And also in this small chip occurs audio signal switching (TV signal, sound off (Mute), the sound from the video-audio input and audio output to the audio-video outputs). So, instead of this small chips can be transistors that perform the same function. As these transistors or the small chip comes komutatsionnuyu sound volume adjusting rapryazhenie from the CPU. So all these chains can be checked.
And if your Kosanov pin-sound chip no sound from the speakers is not observed – you should first check the piping sound chip (electrolytic capacitor tester to check – sample and the new stand to contacts privayanogo – to dry, resistors, diodes – back and forth) . If the binding is intact then we change the sound chip and watch the result. Sometimes the TV uses the noise reduction system. This is where you set up channels and long run through from one channel to another, and instead of the image screen on snow. So out of the speakers at this time it should sound a loud noise (White noise – hiss) which corresponds to the absence of an audio signal at the input. (The usual feature of the FM modulation frequency / fm used for transmitting sound in television).
So there is such a system in some TVs, which blocks the sound signal in the absence of. And the original sound mikroszemu in this case, (if there is no signal) blocking voltage is supplied from the CPU (sometimes usilino transistor and diodes resolved with other blocks). This makes the blocking voltage disconnect output audio chip (sometimes it is not blocking voltage is applied to the original sound chip, and the previous sound-chip komutatsionnuyu). And the fault in the circuit to block the sound can cause a lack of sound at normal operating sound chip. Breakage usually sound blocking circuit can appear when the home television try to connect external speaker with an amplifier to the TV. And it may even be due to a change in the sound soprativleniya resistor chain lock. (This resistor determines the sound blocking threshold) and he stands near the central protsesmora. Его сопротивление может возроста само по себе. И для этого вам понадобится конечно схема. Но такая поломка мне встресалась всего один раз.
Вроде по звуку на сегодня хватит 🙂
Is there sound, the screen is not lit

One common such failure, It is the absence of voltage on the picture tube. If the back of the picture tube is not lit it is necessary to run through the tracks and wires on the voltage contacts (the kinescope) and further fee TDKS. Typically one wire is soldered resistor voltage 2 … 5 th power 2 watt.

List of English abbreviations, Abbreviations and terms, used with a foreign television

* A (audio) - audio, sound
* ABC (auto black control) - Automatic adjustment of the black level
* ABL (automatic beam limiter) - automatic current limiting rays
* AC (alternating current) - alternating current
* AC in - AC voltage input
* AC mains - AC electric power network
* ASS (automatic colour control) - Automatic adjustment of color
* ASA - automatic chroma suppression signal
* ADJ (adjustment) - regulation, podstroyka
* OF (audio frenquency) - af
* AFC (automatic freqency control)* - automatic frequency control
* AFT (automatic fine tuning) - automatic fine tuning
* AGC (automatic gain control) - Automatic Gain Control
* ALC (automatic level control) - automatic level control signal
* AMP (amplifier) - amplifier
* Amplitude control - amplitude adjustment
* ANT - antenna on the acoustic waves
* ARC (automatic phase control) - automatic adjustment phase
* Audio - an audio signal
* Audio out - the output audio signal
* Audio in - input audio signal
* OF (audiovisual) - audiovisual
* AWB (automatic white balance) - Auto White Balance
* BALL (balance) - balance
* Band - range
* WATT (battary) - battery
* BELL - filter "Flared"
* BF (buffer) - buffer
* BF (burst frequency) - color burst signal
* BG (burst gate) - strobe flash pulse
* BLK (blanking) - blanking, zapiranie
* Blocking oscillator - blocking oscillator
* Board - fabric
* BPF (band-pass filter) - a bandpass filter
* BRT (brighness) - brightness
* BSP (bandstop filter) - reject filter
* BUFF (buffer) - buffer
* Burst - Flash
* B-Y - blue color difference signal
* With OUT (colour out) - the output chrominance signal
* Cable - Cable
* CAI (color acceptance improvement) - improve the color scheme
* Capacitance - capacity
* CARR (carrier) - carrier frequency *
* CATV (community antenna television) - cable TV
* CCD (charge-coupled device) - Charge Coupled Device
* CENT (center) - center
* CF (ceramic filter) - ceramic filter
* SN (channel) - channel
* Channel selector - selector channel
* Choke - the choke
* Chroma - color saturation; chrominance signal
* CHINA (chroma in) - an input chrominance signal
* Circuit - scheme
* Circuit diagram - a circuit diagram
* Clamp - fixing level
* CLC (clock) - clock
* CLIP (clipper) - limiter
* Coil - inductor
* WITH (crystal oscillator) - Crystal Oscillator
* COL (color) - Colour, chromaticity
* Comb - Comb Filter
* CONN (connector) - connector
* CONV (converter) - converter
* CORR (correction) - correction
* COST (colour out) - the output chrominance signal
* CPU (central processing unit) - central protsesdor
* Crispener - control definition
* CRT (cathode-ray tube) - cathode-ray tube
* CTI (colour transient improvement) - Adjust the color saturation
* CTL (control) - regulation, management
* CTS (composite television signal) - Complete TV video
* Current — ток
* CVS (composite video signal) - full video
* D2-MAC (duobonar-multiplexed analogue components) - one of the European television systems via satellite
* Damper — демпфер
* Damping - damping, easing
* Data - data
* DC (direct current) - DC
* D.C. amplifier - DC amplifier
* D.C. converter - DC converter
* ON-emph (deemphasis) - predistortion correction
* DEMOD (demodulator) - a demodulator
* THE (detector) - detector
* DEV (deviation) - deviation
* DL (delay line) - Delay Line
* DTV (digital television) - digital television
* DY (deflection yoke) - deflection system
* E. SW (electronic swith) - dongle
* EDTV (enhanced-definition television) - High Definition TV; TVCh
* EF (emitter follower) - émitternyj Repeater
* EMRNA (emphasis) - pre-emphasis
* F (fuse) - fuse
* FASTEXT - predation regime and adopt teletext
* FEQ (frequecy equalizion) - frequency correction
* FH - term frequency
* FLD (field) - field (television pictures)
* FLLP (low-pass filter) - low-pass filter
* FLHP (high-pass filter) - highpass filter
* Flyback - .obratny course (beam)
* FM (frequency modulation) - FM
* Freq. Soplr - frequency correction
* Frequency response - frequency response
* G (GND, Ground) - housing, overall
* Gain - strengthening
* Gate - gate pulse
* GEN (generator) - generator
* GND (ground) - housing, overall
* GRN (ground) - grounding
* G-Y - green color difference signal
* n (horizontal) - horizontal, line
* n. OUT (horizontal output) - the output horizontal scanning
* n. VISIBLE (horizontal syns) - line binhroimpuls
* HD (horizontal drive signal) - horizontal synchronization signal
* HDTV (high-defenition television) - high-definition television,TVCh
* Heater - Heater (kinescope cathode)
* HF (hihg frequence) - high frequency
* HPF (high-pass filter) - highpass filter
* HS (horizontal scanning start pulse) - a trigger pulse line scan
* I / O - (input/output) - enter exit
* 1C (integrate circuit) - integrated circuit (IMS)
* ID (identification) - identification
* IF (intermediate frequency) - an intermediate frequency
* IFA (intermediate frequence amplifier) - intermediate frequency amplifier
* IND (indicator) - LED
* Input circuit - Input circuit
* INV (inverter) - inverter
* AND (infrared) - infrared
* IR - receiver
* IT (Japanese Industrial Standard) - Japanese Industrial Standard
* KILL - suppress, put out
* L (low) - a logic low
* LED (light-emitting diode) - Light-emitting diode
* Level - Level
* LF (low frequency) - low frequency
* LIM (limiter) - limiter
* Line - the line
* Line frequency - chastota strok
* LNA (low-noise amplifier)- Low Noise Amplifier
* THE (local oscillator) - LO
* LPF (low-pass filter) - a low pass filter, FNC
* LSIC (large scale integration circuit) - LSI, BIS
* MAC (multiplexed analog component) - temporary seal of separate components
* Memore - Memory
* MIX (mixer) - mixer
* Mixer - Mixer
* MM (mono multi) - multivibrator
* MOD (modulator) - modulator
* Mode SW (mode switch) - the mode switch
* MP (monolithic processor) - a single-chip microprocessor
* MPU (microprocessor unit) - a microprocessor
* MULTI (multi voltage) - the ability of the device at the time-
* personal supply voltages
* MUTE (muting) - Audio lock
* MX (matrix) - matrix
* NFB (negative feedback) - negative feedback
* NL (noise limiter) - Noise limiter
* NOR (normal) - normal
* Normal operation - normal mode
* NTSC (National Television Standart Code) - national television standard code - the system of the United States of color television
* O.D. (overall dimensions) - dimensions
* OFF - OFF
* then (Organization International Radio and Television) - International Radio and Television Organization
* OSC (oscillator) - generator
* Oscillogram - oscillogram
* OSD (on screen display) - the on-screen display; OSD
* Output - Output
* Output power - Output Power
* PAL (phase alternation line)- Phase Alternating Line - TV color systems(Germany)
* rV (public broadcasting) - television broadcasting
* PD (phase detector) - a phase detector
* THE (picture element) - picture element
* PIC (picture contrast) - kontrastnost'izobrazheniya
* PIP (picture in picture) - PIP (Picture in Picture)
* PLL (phase locked loop) - fazovaya avtopodstroyka
* Power supply - power supply
* Pre. Amp. - preamplifier
* Protect - protection
* PSV (power supply unit) - Power Supply
* Pulse - pulse
* Pulse level - Signal level
* PWB (printed wiring board) - printed circuit board
* PWM (pulse width modulator) - shirokoimpulsnaya modulation, Prosperity
* R, G, AT (red, green, blue) - red, green, Blue - basic
* colors, transmitted in color television; signals of primary colors
* Range - range
* RCP (remote control panel) - remote control,PDU
* Receiver - receiver
* RECT (rectification) - straightening
* REF (reference) - reference signal
* KEG (regulator) - regulator, Voltage regulator
* Reset - Reset
* Resistor - Resistor
* RF (radio frequency) - radiochastota
* RF-converter - a radio frequency transmitter
* RF-out - RF output
* R-Y - red color difference signal
* SAWF (surface accoustic wave filter) - SAW filter
* SC (sand castle) - sandcastle
* SECAM (Sequential Memory System has) - alternate color and memory - color television system (France)
* Selectivity - selectivity
* Semiconductor - semiconductor
* Shield - Screen
* SIF (sound IF) - an intermediate frequency audio signal
* Source - external power
* Speaker - speaker, speaker
* SSC (super sand castle) - super sandcastle
* ST (square tube) - CRT with straightened corners of the screen
* ST BY (stand by) - Standby mode
* STOPPER - stop
* STV (satellite TV) - satellite television
* SUP (supply) - source of power
* SW (switcher) - switch, switch
* SYNC (synchronization) - synchronization signal
* Sync. IF - input sinhrosmesi
* Terminal - contact, input, output
* Test - Testing
* Timer - Timer
* TR (telephone pickup) - phone jack
* TR (test point) - reference point
* TR (transistor) - transistor
* TR SW - transistor switch
* TRANS (transformer) - transformer
* TRAP - Notch
* TV (television) - a television
* TXT (teletext) - teletext
* UHF (ultra high frequency) - deцimetrovыj TV Range-
* Foot broadcasting, DMV
* UJT (unijunction transistor) - unijunction transistor
* V (vertical) - vertical
* V. CENT - vertical alignment control
* V. CENT-SW - switch vertical alignment
* V. UN - linear regulator vertically
* V. OUT - output vertical deflection
* V. SIZE - control the vertical size
* V. SIZE-CORR - stabilization scheme vertical size
* VA (video amplifier) - video amplifier
* VBS (video blanking synchronization) - composite video sig-
* cash, PTS
* YOU (video control) - Output voltage setting
* VCO (voltage controlled oscillator) - generator, managed to-
* stresses
* VCR (video casset recorder) - video recorder
* CEO (vertical deflection) - vertical deviation
* CEO (vertical drive signal) - the frame synchronization signal
* VDD - Supply voltage
* VF (video frequency) - video frequency
* VHP (very high frequency) - m band television broadcasting, MB
* VIDEO - Video image
* Video in - input video signal
* Video out - video output
* VS (vertical scanning start pulse) - start pulse for the vertical scanning
* VTR (video tape recording) - video
* VTS (video tuning system) - TV configuration system
* Wave-Form - Form signal (waves)
* WBL (wide blanking pulse) - a blanking pulse
* WF (waveform) - waveform, signal
* WFM (waveform monitor) - an oscilloscope to monitor the waveform
* White level - the level of white
* Wire - Explorer, tire
* XAMR (horizontal amplifier) - deflection amplifier gorizontalnrgo
* Y (yoke) - deflection system
* Y - brightness signal
* Y / C - signal brightness / chromaticity
* YAMP (vertical amplifier) - vertical amplifier

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