Flat screen TVs and monitors

This is currently a skeleton page. Please help by adding your contributions either here or in the associated Discussion page.

This page will cover flat screen TVs and computer monitors.

Summary

Safety

Warning03.png
As with all mains electrical devices, dangerous voltages may be exposed when opened even if the mains lead is disconnected from the wall socket. Be aware that capacitors store electricity and that the voltage across the terminals may be 100's of volts.

Main section

There are several types of flat screen (flat panel) TV's and monitors. A good starting explanation can be found here: https://en.wikipedia.org/wiki/Flat-panel_display

For completeness we should mention the original CRT (cathode ray tube) screens which were the norm from the first days of television to around the 1980's when plasma and newer technologies started to replace bulky CRTs. CRTs also required very high voltages 10-20KV (10000-20000Volts) which meant repairing required great care.

So what is the distinction between a TV and a monitor? Both display pictures and provide sound, the distinction comes from the source of the picture and sound signals. A TV has a RF (RadioFrequency) tuner (receiver) that the users controls to select the programme they wish to view. It's signals arrive from a remote transmitter and it will have an antenna connected to receive the signals. The signals arrive via radiowaves. A monitor does not have the tuner, instead it is fed from an external source, typically a PC/laptop via cables. That is a somewhat simplistic distinction, yes the monitor can have an external tuner connected like those old "digiboxes". Likewise the TV can have cable inputs from video players, DVD players etc. There are always "grey areas" but the basic difference is the method by which the signal arrives. I will leave the reader to ponder on WiFi and Bluetooth monitors (or is that a TV?), the definition becomes somewhat blurred. The first step is to clearly identify what type of TV/monitor you have because that will help you determine what the basic electronics blocks are. Usually it is fairly obvious but if unsure search the internet for information about the make and model type. The most useful model information is usually found on the back or underneath of the item.

CRT TVs and monitors: Fixing these requires a very clear awareness of high voltages and any opening and repair should be done with full knowledge of how to identify the danger areas. The CRT also requires care with handling, dropping the glass tube which has a vacuum inside can result in an explosion of glass particles which will cause serious injury. Not a job for a repair cafe event.

Plasma TVs and monitors:


LCD TVs and monitors:


LED TVs and monitors: