Using an Oscilloscope

Learning Objectives

• Understand the basic operation of a Cathode Ray Tube

• Understand what an oscilloscope is displaying

• Be able to operate the basic functions of an oscilloscope• Sensitivity control (Volts / division vertical)• Sweep speed (Time / division horizontal)• H position• V position• Automatic (auto) trigger• Trigger level for viewing signals on channels 1 and 2• View signals on channels 1 and 2

• View and describe an unknown signal in terms of:• Amplitude• Frequency• Period• Pulse duration

• View and identify cosmic ray signals from a scintillation counter

Outline

• Introduction

Using an Oscilloscope

Introduction

• Oscilloscopes are common, useful tools for viewing electric signals

• An electric signal is the flow of charge through a conductor

• An oscilloscope displays the voltage which is generated across a resistor (50 ohms or 1 megaohm) as a function of time as the electric signal passes through the resistor

• How is the voltage related to the flow of charge in the electric signal?

• Current = charge flowing past a point (or through a resistor) per unit time.

• Units = charge / time = coulombs / second = Amperes• Variable used is I• Ohm’s law V = I R ; V = voltage, R = resistance

Using an Oscilloscope

Channel 1 Input

Using an Oscilloscope

Channel 2 InputSensitivity controls(Volts / division, vertical)

Sweep speed(Time / division, horizontal)

V position H position Trigger levelDisplay (Cathode Ray Tube)

Voltage

Time

Cathode Ray Tube

Using an Oscilloscope

Slide template

Using an Oscilloscope