Listed below are some of the questions which keep popping in your mind if you are new to electronics, or haven’t got enough time to study about them. Although these questions are very basic, but most of the people really don’t know the exact and logical answers.

Q: What is electronics ?
A: A Technology involving the manipulation of voltages and electric currents through the use of various devices for the purpose of performing some useful action. This large field is generally divided into two primary areas, analog electronics and digital electronics.

Analog Electronics
Historically, analog electronics was used in large part because of the ease with which circuits could be implemented with analog devices. However, as signals have become more complex, and the ability to fabricate extremely complex digital circuits has increased, the disadvantages of analog electronics have increased in importance, while the importance of simplicity has declined.

Digital Electronics
The advent of the transistor in the 1940s made it possible to design simple, inexpensive digital electronic circuits and initiated the explosive growth of digital electronics. Digital signals are represented by a finite set of states rather than a voltage, as is the case for the analog signal. Typically, a digital signal takes on the value 0 or 1; such a signal is called a binary signal. Because digital signals have only a finite set of states, they are amenable to error-correction techniques; this feature gives digital electronics its principal advantage over analog electronics.

In common two-level digital electronics, signals are manipulated mathematically. These mathematical operations are known as . The operations permissible in boolean algebra are NOT, AND, OR, and XOR, plus various combinations of these elemental operations.See also Boolean algebra.

The microprocessor is the most important integrated circuit to arise from the field of electronics. This circuit consists of a set of subcircuits that can perform the tasks necessary for computation and are the heart of modern computers. Microprocessors that understand large numbers of instructions are called complete instruction set computers (CISCs), and microprocessors that have only a very limited instruction set are called reduced instruction set computers (RISCs).

Q: What is the difference between current and voltage?

A: The difference between current and voltage is often compared to water travelling through a pipe. 

The current measures how much water travels through the pipe. Sometimes you have a big pipe and sometimes you have a little pipe, but neither matters for the current – the current simply measures how much water goes through it. Likewise, “current” means the number of electrons that travel through a wire. 

The voltage is a measure of how hard the water is being pushed through the pipe. If you’ve got a huge pump driving water through a pipe, the water is pushed through hard. If the pump isn’t working well, it isn’t. Voltage is a measure of the potential difference between one place and another.

Q: What is a resistor ?

A: One of the three basic passive components of an electric circuit that displays a voltage drop across its terminals and produces heat when an electric current passes through it. The electrical resistance, measured in Ohms, is equal to the ratio of the voltage drop across the resistor terminals measured in volts divided by the current measured in amperes. See also Ohm’s law.

Resistors are described by stating their total resistance in ohms along with their safe power-dissipating ability in watts. The tolerance and temperature coefficent of the resistance value may also be given.

Q: Why do you need resistors?

A: Resistors are used for a variety of purposes: to allow voltage levels to be reduced when in series circuits, to divide current when used in parallel,to discharge capacitors, to assert the output level of tri-state and to protect circuits from damage.

Q: What is a transistor ?

A: A transistor is an electronic component known as a semiconductor. The transistor was developed in the mid 1900s and became an alternative to vacuum tubes (valves) and relays. Early transistors were made with germanium but silicon is used almost universally in semiconductor manufacturing.

A single transistor is a few millimetres wide and tall and has three terminals. It works by transferring a high resistance input to a lower resistance output. The transfer of resistance gave rise to the name trans – istor. A transistor will generate a large change in current for a given input or a large change in voltage.

There are numerous ways to use them and the applications and science of the transistor can fill many books – too complex to discuss in detail in this answer. Transistors are good amplifiers and are found in radios, music equipment, video systems in their role as an amplifier. They are also very efficient switches and because they will switch from low to high, are common in binary circuits. The transistor is the basis of all digital computers.

A modern CPU chip in a computer is actually made of many thousands of transistors inside the integrated circuit. A typical computer will have millions of transistors in total. For further reading, take a look for basic electronics tutorials. All of them will have detailed descriptions of the way a transistor works and demonstrate the more common applications.

This is uptil now, in next post we will cover more components like capacitors, diodes, inductors and more if digital side. If you come up with more questions, please post in reply section.

Happy ElectronicsING =)