Concepts & Components Frank Shapleigh Basic Electronics Concepts & Components Frank Shapleigh

Thales (624 – 547 BC) Wrote about the attraction of small pieces of straw & dust to amber (fossilized tree sap) that had been rubbed by a cloth. The Greek for amber is ELEKTRON

Charles Coulomb (1736-1806) Discovered the law which determines the force between electrically charged objects The Coulomb is the unit of electric charge

Alessandro Volta (1745-1827) Determined that electricity could be produced by a combination of 2 different metals in contact with a cloth moistened with salt water. The Volt is the unit of Electric Potential Difference

Hans Oersted (1777-1851) Discovered that a current flowing through a wire produced a magnetic field The Oersted is one unit of magnetism

Andre Ampere (1775-1836) Proposed the correct theory of the electro-magnetic force. The Ampere is the unit of electric current

Michael Faraday (1791-1867) Discovered the principle of Electro-magnetic Induction Invented the Electric Motor The Farad is the unit of capacitance

Georg Ohm (1789-1854) Discovered the law which relates the current and voltage in an electric circuit The Ohm is the unit of electric resistance in a conductor

J.J. Thompson (1856-1940) In 1897 Thompson discovered the Electron. The manipulation of this sub-atomic particle is called electronics. Thompson won the nobel prize for Physics in 1906

Thomas Alva Edison In his lifetime Edison patented 1,093 inventions. His most famous invention was the incandescent light bulb. He also invented the phonograph and an early movie film projector.

Samuel Morse Morse was not a scientist but a professional artist. On an ocean voyage he over heard a conversation on electromagnets He invented the telegraph and the code that bears his name. The first telegraph message was sent in 1844.

Guglielmo Marconi Marconi did not invent the concept of radio but did develop the first practical inventions in radio telegraphy over long distances Marconi received the first trans-Atlantic radio signal at Signal Hill in St. John’s in 1901 Marconi received the Nobel Prize in Physics in 1906.

Fleming and De Forest Sir Ambrose Fleming invented the diode vacuum tube in 1902 Lee De Forest invented the vacuum tube amplifier in 1906 Both these developments led to the radio, long distance phone service, the television, and the first computer.

Shockley, Bardeen, & Brattain Shockley, Bardeen, and Brattain are credited with the research that led to the invention of the transistor in 1948. This device forms the basis of all electronic devices used today including computers They were awarded the Nobel Prize in Physics for 1956

Kilby and Noyce Jack Kilby and Robert Noyce, working independently, invented the Integrated Circuit or Microchip in 1958. Noyce was one of the founders of Intel, the world’s largest “chip” maker. You are reading this on a computer using an Intel processor. Kilby invented the calculator and won the Nobel prize in Physics in 2000.

The Simplest Circuit The simplest circuit consists of: A source of electrical current A conducting path A control element (Switch) Something that converts electrical energy to some other form of energy (called a load resistance) An Open Circuit has no complete path for current flow, a Closed Circuit does!

Simplest Circuit (cont’d) When the control element is activated (a switch closing), current will flow in the circuit until the energy of the source is exhausted. A circuit diagram using standard symbols is called a Schematic from the Latin Schema (plan).

Simplest Circuit (cont’d) There are a number of electrical parameters (measurements) that are of importance. The 3 most basic are: Electric Potential Difference - measured in Volts Electric Current - measured in Amperes Resistance - measured in Ohms

Simplest Circuit (cont’d) Electric Potential Difference can be very loosely defined as the “electric pressure” which forces electric current through a conductor Electric Current is the flow of electric charge through a conductor is a unit of time Resistance is the opposition to the flow of current through the conductor

Simplest Circuit (cont’d) In the next slide, a voltmeter and an ammeter are used to measure the electrical properties of a circuit It is important to connect these devices to the circuit in the proper way

Simplest Circuit (cont’d) The 3 parameters of an electrical circuit are related mathematically. That relationship is defined by “Ohm’s Law” and is: E = IR or more commonly V=IR V = Electric Potential (volts) I = Current (amps) R = Resistance (ohms)

Sample Calculation – Ohm’s Law Sample Problem: The voltage is measured at 3 volts and the current at 0.5 amperes. What is the resistance of the load resistor? Given: V = 3v, I = 0.5a, R = ? Solving for R R = V / I R = 3 /0.5 R = 6R

Simplest Circuit (cont’d) There are other electrical parameters that can be measured such as Power (Watts) & Energy (Joules) The diagram on the right is used by technicians

Electronic Components A basic knowledge of electronics is not complete unless the student can identify the basic components. A useful exercise is to take a surplus /obsolete circuit board and identify as many components as possible. The following slides will help identify common components.