Learning to Work Efficiently and Accurately

Example 1: Express 18,000 in scientific notation POWERS OF 10 The base 10 is commonly used in electronics because multiples of 10 are used in the metric system of units. SCIENTIFIC NOTATION A number is said to be written in scientific notation if it is written as the product of a number greater than or equal to 1 and less than 10 and a power of ten. Example 1: Express 18,000 in scientific notation Example 2: Express 0.000056 in scientific notation ENGINEERING NOTATION AND METRIC PREFIXES Very much like scientific notation the power of 10 are always multiples of 3

Quantity Symbol Unit Unit Symbol Capacitance C farad F Conductance G siemens S Electric charge Q coulomb C Electromotive force E volt V Current I Ampere A Frequency f hertz Hz Inductance L Henry H Power P watt W Resistance R ohm  Reactance X ohm  Impedance Z ohm 

giga- G 109 mega- M 106 kilo- k 103 milli- m 10-3 micro-  10-6 Metric Prefixes Prefix Symbol Scientific Notation tera- T 1012 giga- G 109 mega- M 106 kilo- k 103 milli- m 10-3 micro-  10-6 nano- n 10-9 pico- p 10-12

Direct current (DC): constant value that does not change with time Alternating current (AC): magnitude and direction varies with time Rectifier: Device that converts AC to DC Frequency (f): number of cycles per second and unit is Hertz Period (T): amount of time for complete one cycle Frequency and Period conversion: f = 1/T OR T = 1/ f ( T in Second and f in Hz )

Vpeak = Vp-p / 2 Vrms = 0.707 x Vpeak Vpeak = Vrms / 0.707 Voltage and current in phase Voltage leading current 60 degree Vpeak = Vp-p / 2 Vrms = 0.707 x Vpeak Vpeak = Vrms / 0.707 Vaverage = 0.637 x Vpeak cosine leading sine 90 degree

RESISTOR COLOR CODE General purpose Resistor 4-bands Opposite to the current flow General purpose Resistor 4-bands Precision Resistor 5-bands

Black - 0 100 - Brown 1 1 101 - Red 2 2 102 - Orange 3 3 103 - GENERAL PURPOSE RESISTOR COLOR CODE First band Second band Third band Fourth band Color First Digit Second Digit Multiplier Tolerance Black - 0 100 - Brown 1 1 101 - Red 2 2 102 - Orange 3 3 103 - Yellow 4 4 104 - Green 5 5 105 - Blue 6 6 106 - Violet 7 7 107 - Gray 8 8 108 - White 9 9 109 - Gold - - 10-1 +/-5% Silver - - 10-2 +/-10% None - - - +/-20%

Black - 0 0 100 - Brown 1 1 1 101 +/-1% Red 2 2 2 102 +/-2% PRECISION RESISTOR COLOR CODE Color First Second Third Multiplier Tolerance Digit Digit Digit Black - 0 0 100 - Brown 1 1 1 101 +/-1% Red 2 2 2 102 +/-2% Orange 3 3 3 103 - Yellow 4 4 4 104 - Green 5 5 5 105 +/-0.5% Blue 6 6 6 106 +/-0.25% Violet 7 7 7 107 +/0.1% Gray 8 8 8 108 - White 9 9 9 109 - Gold - - - 10-1 - Silver - - - 10-2 -

Resistor Wattage Rating The larger the wattage, the greater the cost The larger the wattage, the greater size and area the resistor occupies within the equipment

Superposition Theorem In a network with two or more sources, the current or voltage for any component is the algebraic sum of the effects produced by each source acting separately. useful to solve the circuit with two or more voltages or current sources. To use one source at a time, all other sources are “killed” temporarily. To “killed” voltage source: short circuit across its potential difference. To “killed” current source: open circuit The method is to calculate the voltage or current by each source separately and then superimpose these voltages or currents.

Thevenin’s Theorem Find VTH Find RTH very useful in simplifying the process of solving for the unknown values of voltage and current in a network. RTH VTH A B + A Network - B Find VTH Remove the load from the circuit VTH is the voltage of the open circuit Find RTH Remove the load Killed all voltage sources by short circuit Killed all current sources by open circuit Resistance looking into the open circuit is RTH

DMM (Digital Multimeter) Measure: TEST EQUIPMENTS: DMM (Digital Multimeter) Measure: DC and AC (Vrms) voltages DC and AC (Irms) currents Resistance (Ohm) Continuing Option: Capacitance Diode Frequency

Signal displays on the Oscilloscope

TEST EQUIPMENTS: The OSCILLOSCOPE Time Domain Measure DC voltage Measure AC voltage ( Vpeak-to-peak ) Measure Time (Period ) then to get Frequency using F = 1/ T Measure phase angle difference Measure time then using formula to calculate the angle.

TEST EQUIPMENT: FUNCTION GENERATOR Generates Sine-wave, Triangle-wave, Square-wave …