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How to repair TV
SCHEMATICS AND REPAIR MANUALS FOR OLDER TV SETS:
Old TV Schematics and television repair manuals. A large number of old TV set schematics and service information for vintage collectable television sets...old black and white tube TVs & early transistor color television sets. Service info usually includes alignment instructions, response curves, waveforms, voltage charts, troubleshooting tips and, of course, TV set schematics.[1] - thanks to dr-fix-it.com More details.
How To Repair Your Plasma TV With a Baseball Bat (NSFW)
hat rumor that Australian toilets flush the other way isn't true, so lets start a new one: In Australia, you can fix things by beating them. See you in my children, new trivia meme![2] - thanks to gizmodo.com More details.
How to Repair TV,VCR,CABLE,DVD, Remote Control Quick & Easy
Has your remote control stopped working ? Do you need to push hard on the buttons ? Do some buttons work but not all the buttons ?
This instruction will guide you through fixing your troublesome remote. You may think some of the procedures are a bit extreme but trust me I know what I am talking about.[3] - thanks to ehow.com More details.
Television receiver fundamentals
The basic color television receiver must perform the same functions today as 40 years ago. (Since B/W is a subset of the color standard, most references in this document will be for color except as noted). A studio video monitor includes all of the functions of a television receiver except the tuner and IF (which rarely fail except for bad connections or perhaps lightning strikes to the antenna or cable connection). Therefore most of the repair information in this document is applicable to both TVs and studio monitors.[4] - thanks to repairfaq.org More details.
Repair or replace
If you can do the repairs yourself, the equation changes dramatically as your parts costs will be 1/2 to 1/4 of what a professional will charge and of course your time is free. The educational aspects may also be appealing. You will learn a lot in the process. Thus, it may make sense to repair that old clunker for your game room or beach house. (I would suggest the kid's room but most TV watching just rots the brain anyhow so a broken TV may be more worthwhile educationally than one that works.) [5] - thanks to repairfaq.org More details.
TV Receivers 101
Low voltage power supply (some may also be part of (2).) Most of the lower voltages used in the TV may be derived from the horizontal deflection circuits. Sometimes, there is a separate switching power supply but this would be the exception. Rectifier/filter capacitor/regulator from AC line provides the B+ to the switching power supply or horizontal deflection system. Degauss operates off of the line whenever power is turned on (after having been off for a few minutes) to demagnetize the CRT. [6] - thanks to repairfaq.org More details.
TV Troubleshooting
Major parts of nearly all modern TVs and many computer monitors are directly connected to the AC line - there is no power transformer to provide the essential barrier for safety and to minimize the risk of equipment damage. In the majority of designs, the live parts of the TV or monitor are limited to the AC input and line filter, degauss circuit, bridge rectifier and main filter capacitor(s), low voltage (B+) regulator (if any), horizontal output transistor and primary side of the flyback (LOPT) transformer, and parts of the startup circuit and standby power supply[7] - thanks to repairfaq.org More details.
Safe discharging of capacitors in TVs and video monitors
It is essential - for your safety and to prevent damage to the device under test as well as your test equipment - that large or high voltage capacitors be fully discharged before measurements are made, soldering is attempted, or the circuitry is touched in any way. Some of the large filter capacitors commonly found in line operated equipment store a potentially lethal charge. [8] - thanks to repairfaq.org More details.
Removing the CRT HV connector
The rubber part is usually not glued down so it can be lifted rather easily. However, there may be some silicone type grease between the rubber boot (that looks like a suction cup) and the CRT glass to seal out dust.
A metal clip with a spring keeping it spread out attaches inside the button. [9] - thanks to repairfaq.org More details.
Safe troubleshooting techniques for line powered TVs
TVs are particularly dangerous with respect to troubleshooting due to the fact that a substantial portion of their circuitry - sometimes all of it - is directly line connected. Even if your are working in a totally unrelated area like the sound circuits, awareness of the general design and location of the line-connected circuits can prove to be a life saver.
These designs may take several forms: [10] - thanks to repairfaq.org More details.
Getting inside a TV
You will void the warranty - at least in principle. There are usually no warranty seals on a TV so unless you cause visible damage or mangle the screws, it is unlikely that this would be detected. You need to decide. A TV still under warranty should probably be returned for warranty service for any covered problems except those with the most obvious and easy solutions. Another advantage of using warranty service is that should your problem actually be covered by a design change,[11] - thanks to repairfaq.org More details.
Specific considerations before poking around inside a TV or monitor
Main filter capacitor(s). This is the most dangerous (not the HV as you would expect). Fortunately, these capacitors will normally discharge in a few minutes or less especially if the unit is basically working as the load will normally discharge the capacitors nearly fully as power is turned off. With TVs, the main filter capacitor is nearly always on the mainboard. Monitors are more likely to have a separate power supply module.[12] - thanks to repairfaq.org More details.
Dusting out the inside of a TV
Use a soft brush (like a new paintbrush) and a vacuum cleaner to carefully remove the built up dust. Blowing off the dust will likely not hurt the TV unless it gets redeposited inside various controls or switches but will be bad for your lungs - and will spread it all over the room. Don't turn anything - many critical adjustments masquerade as screws that just beg to be tightened. Resist the impulse for being neat and tidy until you know exactly what you are doing.[13] - thanks to repairfaq.org More details.
Troubleshooting a TV with the mainboard disconnected
There are times when it is desirable to remove the chassis or mainboard and work on it in a convenient location without having to worry about the equipment which will simulate the critical functions but this is rarely an option for the doit-yourselfer.
My approach is usually to do as much work as possible without removing the main board and not attempt to power it up when disconnected since there are too many unknowns. [14] - thanks to repairfaq.org More details.
User picture adjustment
For general viewing, subdued lighting but not total darkness is probably best. However, for most dramatic impact, a darkened environment may be preferred. Make the following adjustments under the expected viewing conditions.
Tune to a strong channel or play a good quality tape. [15] - thanks to repairfaq.org More details.
Adjustment of the internal SCREEN and color controls
The screen should be adjusted with a white pattern (snow from the tuner should do or turn the user COLOR control all the way down to get a black and white picture). Put the set in Service mode (horizontal line) if it has such a switch in the back or inside. If not, just use the raster in a darkened room. Adjust screen for a dim white line (raster). If the line is not white at its dimmest point, you will need to adjust the drive and cutoff controls for R, G, & B. [16] - thanks to repairfaq.org More details.
Color balance adjustment
Note: Some TV designs (Zenith uses this in a few models) automatically balance CRT cathode drive by sensing emission from the red, green, and blue guns using a gray scale reference pulse outside the viewable picture. If this is the case with your set, there may be no user OR service adjustments [17] - thanks to repairfaq.org More details.
Low Voltage Power Supply Problems
TVs require a variety of voltages (at various power levels) to function. The function of the low voltage power supply is to take the AC line input of either 115 VAC 60 Hz (220 VAC 50 Hz or other AC power in Europe and elsewhere) and produce some of these DC voltages. In all cases, the power to the horizontal output transistor of the horizontal deflection system is obtained directly from the low voltage power supply. In some cases,[18] - thanks to repairfaq.org More details.
