Using an Oscilloscope: Introduction

If you watch an electrical engineer tackling a tough design project, or a service engineer (technician) troubleshooting a stubborn problem, you’ll see them grab a scope, fit probes or cables, and start turning knobs and setting switches without ever seeming to glance at the front panel. To these experienced users, the oscilloscope is their most important tool but their minds are focused on solving the problem, not on using the scope.

Making oscilloscope measurements is second nature to them. It can be for you too, but before you can duplicate the ease with which they use a scope, you will need to concentrate on learning about the scope itself: both how it works and how to make it work for you.

The purpose of this primer is to help you learn enough about oscilloscopes and oscilloscope measurements that you will be able to use these measurement tools quickly, easily, and accurately.

Using an Oscilloscope is divided into two parts:

The first four Sections of Part I describe the functional parts of scopes and the controls associated with those parts. Then a Section on probes concludes the section.

Part II allows you to build on the knowledge and experience you gained from Part I. The signals you’ll see on the screen of an oscilloscope are identified by waveshape and the terms for parts of waveforms are discussed. The next two Sections cover safety topics and instrument set-up procedures.

Then Section 9 describes measurement techniques. Exercises there let you practice some basic measurements, and several examples of advanced techniques that can help you make more accurate and convenient measurements are also included. The last Section in this primer discusses oscilloscope performance and its effects on your measurements.

Having a scope in front of you while working through the Sections is the best way to both learn and practice applying your new knowledge. While the fundamentals will apply to almost any scope, the exercises and illustrations use two specific instruments: the Tektronix 2213A and 2215A Portable Oscilloscopes. These are classic analog Oscilloscopes, readily available on eBay, and are still considered modern and useful despite their age. Other analog ‘scopes from Leader, Hitachi or even “vintage” brands such as Heathkit are also useful once calibrated.

The 2213A is a dual-channel, 60 MHz portable designed as an easy-to-use, lightweight, general-purpose oscilloscope. The 2215A is a dual time base oscilloscope with more features and capabilities; it’s included so you will understand dual time base scopes and appreciate the additional measurement capabilities they offer.