Electronic Components and Power Supply Basics

Power Supply Voltage Outputs

• Transformer primary windings operate at 250VAC.
• Transformer secondary windings output 50VAC.
• Rectifier stage provides 50VDC from diode outputs.
• Filter stage maintains 50VDC at capacitor terminals.
• Final output from the regulator stage is also 50VDC.

Electronic Component Defects

• Diodes: Can be OPEN or SHORTED; check with Rx10.
• Capacitors: Possible faults include OPEN, SHORTED, or LEAKY; use appropriate range according to capacity value.
• Transistors: May be found SHORTED or OPEN; check with Rx10.
• Resistors: Can be SHORTED, OPEN, or exhibit CHANGE IN RESISTANCE; testing range depends on the third stripe.

LCD Television Components and Functions

• LCD Front Panel: Produces visual output.
• Backlight: Illuminates the display.
• Power Board: Converts AC to DC, distributing power.
• Mainboard: Coordinates functionality of various components.
• Jackpack Section: Houses ports for external devices.
• Inverter Board: Converts DC to AC for backlight.

Common LCD TV Faults and Remedies

• Timing Control Board: Faults include white display, no display, and double images; remedy involves replacing the board.
• Inverter Board: Issues may manifest as distortion with vertical bars.
• Main Board: Can cause multiple faults on the screen.
• Power Board: May present with vertical or horizontal lines across the display.
• Jack Pack Section: Can lead to screen issues if defective.
• Speakers: Symptoms include no power or low power output.
• Liquid Crystal Display: Can fail with white display and intermittent power issues.

Washing Machine Components and Faults

• Motor: Responsible for rotating the drum; failure may result in weak or no pulsator rotation.
• PCB: Control panel location.
• Timer: Sets wash cycle duration.
• Fuse: Protects against electric overload.
• AC Chord: Connects the washing machine to the power source.

Common Washing Machine Faults and Remedies

• No Power: Check AC chord, fuse, or dirty contacts; inspect with an ohmmeter.
• Weak Pulsator Rotation: Inspect motor windings for fault.
• No Rotation with Motor Sound: May indicate defects in the capacitor or timer.
• Water Drain Failure: Check belt and gearbox for proper functionality.
• Pulsator Rotates in One Direction: Faulty components like the rubber plug may need checking.
• Heat Not Produced: The magnetron may be defective; also check oven lamp and test components individually.

Microwave Oven Components and Functions

• Magnetron: Produces microwaves for heating food.
• Oven Lamp: Illuminates the chamber.
• High Voltage Transformer: Steps up the primary voltage.
• Waveguide: Directs microwave flow to the cooking chamber.
• Turntable: Ensures even heat distribution.
• High Voltage Capacitor: Doubles high voltage from the transformer with the help of the rectifier diode.
• Thermal Cut-out/Thermostat: Protects against overheating.