Use a Resistor to Measure Inductance
Inductance is usually measured by using an LCM multimeter. It can also be mesured using a resistor. With the resistor method, you adjust the frequency of a sine wave until the AC voltage accross the resistor and inductor are equal. Then using a formula to calculate the inductance. More ...
Electromagnetic Devices
Electromagnetic devices work based on the relationship between electrical current and a magnetic field. They are used to control valves, cooling and heating systems, relays, and electric motors. More ...
Bipolar Transistors
Transistors are semiconductor devices used to amplify or switch electronic signals. Transistors are one of the basic building blocks of modern electronics. There are basically two types of transistors, Bipolar Junction Transistors (BJT) and Field Effect Transistors (FET). More ...
Magnetism
Electric currents and magnetic fields are closely related. Whenever an electric current flows a magnetic field accompanies the current. When a wire is coiled up, the resulting magnetic flux becomes more concentrated. More ...
RC Filters
An RC filter can accept input sinewave signals and block certain bands of frquencies, thus allowing to pass only desired frquencies. This section describes passive RC filters. A passive RC filter uses only resistors and capacitors. More ...
Phase shift in AC Circuits
In an AC circuit with a capacitor or an inductor there is a phase shift between voltage and current. In this article you learn how to calculate the amount of that phase shift. More ...
How to Calculate Impedance
Impedance is one of the most difficult things the electronics technician student needs to calculate. To calculate impedance, you must know the value of all resistors and the impedance of all inductors and capacitors in the circuit. Then you can calculate impedance using a simple mathematical formula. More ...
Superposition Theorem
The resistive networks that satisfy Ohm's law allow a number of simplifying approaches to be taken in their analysis. Circuit analysis by superposition replaces all voltage sources but one with short circuits, then using the summation rules of series-parallel combinations of resistors determine the voltage across and current in each branch due to the remaining voltage source, and then repeating this process for all voltage sources and superposing the results. More ...
Inductors in Series and Parallel
With inductors connected in series, the total inductance is the sum of the inductances of the individual inductors With inductors in parallel, the reciprocal of the equivalent inductance is the sum of the reciprocals of the inductors connected in parallel. More ...
How to Read a Capacitor's Values
Due to the limited space available for printing, physically small capacitors are especially difficult to read. Therefore capacitors use a wide variety of codes to describe their characteristics. More ...
Lead-Acid Battery Chemistry
As a lead-acid battery is repeatedly recharged, sulfation will build-up on the plates and the battery will begin to loose its capacity to restore to a full charge and eventually must be replaced. More ...
Junction Field Effect Transistor (JFET)
A Junction Field Effect Transistor (JFET) consists of a channel and a pn junction. The gate controls the conductance of the channel. A JFET is a voltage controlled device, therefore no current flows into the gate. More ...
Integrated Circuit Manufacturing CMOS Technology
The MOSFET (metal-oxide-semiconductor field-effect transistor) is the dominant device used in modern integrated circuits because it can be scaled to smaller dimensions than other types of devices. More ...
Conductors and Insulators
Materials can be classified depending on whether they allow charge to move. If charge can easily move through a material, these materials are called conductors. If charge cannot move through a material, then this material is called an insulator. More ...
