Maintenance projects

Color TV-Burns insurance maintenance method

Two kinds of TV fuse, serious and minor refers to fuse burned slightly, put a new fuse in General can be. Serious, refers to fuse the metal burns to broken or burnt. If you're going to put on a good fuse, a boot you will see fuses light and immediately burned. A power fuse, you cannot repair voltage using the voltage measurement method, only using the resistance measurements resistance law overhaul. Cause serious burning fuse causes: is often one circuit, short circuit or to change the value of up to two parts. Bad part is after the fuse circuit, mostly the degaussing circuit, 220 rectifier circuits, and switches. Most easily damaged parts are:-----degaussing degaussing coil resistance. Rectifier-----four two bridge rectifier tube, which has a diode damaged; four in bridge rectifier diodes in parallel capacitors, there is a damaged; 300V filtering electrolytic loss in air pressure or leakage switching power short circuit there-------------switch power switch left and right short circuit contacts, choke coil short circuit the two groups. Whether the circuit board has burnt
observation: a closer look at these parts have burned, bursting, discoloration, or is there a smell. Wearing parts and fragile parts measurement: degaussing resistance measurements: solder degaussing resistance in the ear with his hand shaking, heard a noise is bad. Universal table resistors can also be used to measure its resistance, less than 10 euro here is bad, normal value is around 0,02K diode or bridge rectifier IC measurement: best welding measure, at least, to weld one foot, as it has forward and backward on the road is difficult to be measured more accurately, using the maximum resistance to measure reverse resistance should be infinite. Capacitance measurement: General circuit board using the measured on, often with our naked eyes can see burn and smell of burned and 300 volts filtering electrolytic: eyes don't see burned, sometimes universal table measurement, because the pressure is too high. Switch measurements: a document using the greatest resistance, black pens measuring collector, red table measuring base and emitter, normal switch universal hands should not be any bit of swing. Swing is a bad tube. Because of its parts operating at high voltage, universal table cannot be measuring its resistance to pressure most of the time, resulting in measurement errors error: 1000V, for example switch, diode voltage 500V, electrolytic 400V voltage, so it must be above shall prevail. BACK PAGE