About Nebraska Institute of Technology

Before you can diagnose a failed component, you need to understand how electricity behaves. We cover voltage, current, resistance, and power — not as abstract formulas, but as measurable properties you'll observe in live circuits. You'll learn Ohm's law by measuring real loads. You'll understand the difference between AC and DC behavior in appliance circuits, how household 120V and 240V systems are wired, and how to safely work with both.

From there, we move into series and parallel circuits, voltage dividers, current limiting, and the behavior of reactive components (capacitors and inductors) in AC circuits. You'll understand impedance, phase relationships, and why a motor start capacitor has a specific microfarad rating — not just what rating to order.

We go component by component. Resistors — carbon film, metal film, wirewound, fusible — and how each type fails differently. Capacitors — electrolytic, ceramic, film — and why an electrolytic cap near a heat source is a ticking clock. Diodes, rectifiers, and how a single shorted diode in a bridge rectifier changes the entire output waveform. Transistors and MOSFETs — how they switch, how they amplify, and what thermal runaway looks like on a board.

You'll learn to read component markings, decode color bands, interpret SMD codes, and visually identify common failure modes: bulging caps, cracked solder joints, heat-discolored resistors, and burned traces. Then you'll confirm what your eyes see with a multimeter, ESR meter, and oscilloscope.

A schematic is a map of how a circuit thinks. We teach you to read them — following signal flow from input to output, identifying power supply stages, control logic sections, and output driver circuits. You'll learn standard symbols, reference designators, and how to cross-reference a schematic to the physical layout of a PCB.

On the board itself, you'll trace copper pathways, identify power planes and signal traces, understand via connections between layers, and locate test points for measurement. When a trace is burned or a pad is lifted, you'll know how to repair it. When a schematic isn't available, you'll learn to reverse-engineer a circuit by following traces and identifying component functions from their placement and values.

Modern appliances are embedded systems. A refrigerator's main board reads thermistor inputs, drives compressor relays through transistor switching stages, manages defrost cycles with timed logic, and controls fan motors and damper actuators — all coordinated by a microcontroller running firmware. We break down each of these subsystems.

You'll study how sensor circuits convert physical measurements (temperature, pressure, position) into electrical signals. How those signals are conditioned, filtered, and read by control logic. How output stages amplify low-power control signals to drive high-current loads like compressor motors, heating elements, and solenoid valves. Across washers, dryers, dishwashers, ranges, refrigerators, freezers, microwave ovens, and ice machines — every appliance becomes a case study in applied electronics.

Your multimeter is your most important tool, and most people only use a fraction of it. We cover DC and AC voltage measurement, resistance and continuity testing, diode check mode, capacitance measurement, and current measurement — including when and how to use a clamp meter for non-invasive current readings on live appliance circuits.

Beyond the multimeter, we introduce ESR (equivalent series resistance) testing for in-circuit capacitor evaluation, and oscilloscope use for observing waveforms — PWM signals from motor controllers, rectified AC from power supplies, and switching transients from relay contacts. You'll learn what a healthy signal looks like and what a failing circuit shows you before it goes completely dead.

Electronics work is precise, and it can be dangerous. We start every student with thorough safety training: lockout/tagout procedures, safe discharge of capacitors (including high-voltage caps in microwave oven circuits), proper grounding practices, and the physiological effects of electrical shock. You'll learn to respect stored energy — a charged capacitor in a microwave magnetron circuit holds enough energy to be lethal even after the unit is unplugged.

We also cover proper use of hand tools, soldering and desoldering technique, ESD (electrostatic discharge) precautions when handling sensitive semiconductor components, and shop organization for safe and efficient work. All training takes place in a supervised lab environment in partnership with Metro TV and Appliance Service.