Time Varying Signals

DC and AC Signal DC Signal: constant currents and voltages AC Signal: time-varying currents and voltages

Sinusoid Signal A- Peak value B- Peak to Peak Value C- Time period

Mathematical Representation Sinusoid = A + B cos (t + ) Where A – DC offset B – Amplitude =2f where f is frequency of sinusoid  = phase shift

A.C. Signal Analysis FUNCTION GENERATOR (Equivalent to Power supply) OSCILLOSCOPE (Equivalent to Multi-meter)

FUNCTION GENERATOR

FUNCTION GENERATOR

Things to Remember Function – Select between Sinusoid, Square and Triangle wave. Frequency Range- Allows you to select Frequency of the wave. Amplitude – Allows you to set the amplitude of the wave

Display Of Signal - Oscilloscope Front Panel

Front Panel Of Oscilloscope Acquiring Signal User set Condition

Run Control Menu Run/Stop (Green): Instrument is continuously acquiring data Run/Stop (Red): Instrument has stopped Acquiring data SINGLE : Instrument will wait for the user defined event (typically voltage set by the user)

Trigger Menu Trigger tells the oscilloscope when to start acquiring data. Normally edge triggering is done

Triggering modes Normal mode: Displays a waveform when the trigger conditions are met. Used for very short signals Auto mode: Displays a waveform when the trigger conditions are met. Used for all signals Auto-level mode: can be used only when EDGE is selected on the front panel

Coupling Modes DC Coupling : Allows both D.C. and A.C. signal to flow in to the trigger path. AC coupling : Allows A.C only

Horizontal & Vertical Adjustments B A & B : Horizontal Controls C & D: Vertical Controls C D

QUIZ – NEXT WEEK ( BASED ON OSCILLOSCOPE)