Electrical Diagnosis, Test Equipment

What Does An Oscilloscope Do

What does an oscilloscope do? Well, it is probably one of the most intimidating looking pieces of diagnostic test equipment out there, butit is pretty basic in nature. An Oscilloscope is basically a test instrument that graphically displays what is happening electrically. It is Voltage over time. When you look at the display, you will see small squares that run up and across the face. Each display is divided by an 8 x 10 division graticuled screen that signifies the X and the Y coordinates of the graph. There are knobs on the face of the Oscilloscope that allow you to control how many volts per division (or volts per square) and time per division (milliseconds to seconds) per square. The Y axis is the vertical display while the X axis is the horizontal display. The purpose of the oscilloscope is to tell what the peak volts are doing across a certain amount of time. There are 2 main types of Oscilloscopes. The analog and the digital storage. The analog is best for showing what is exactly happening RIGHT NOW. The only problem with an analog Oscilloscope is that it can’t show a glitch very well because they happen so fast you will not see them. Whereas a digital storage Oscilloscope (DSO) actually records every event and plays them back so you are able to see the glitch event. This is why most automotive applications use a DSO versus an analog Oscilloscope. There are 2 channel and up to 8 channel Oscilloscopes that allow you to watch many different things happening at the same time. This is a great asset when trying to pinpoint an intermittent issue.

Below are the to main types of Oscilloscopes. The Analog and the Digital Storage Oscilloscope or DSO. Both are made by Tektronix. The leader in Oscilloscopes and one of the best made Oscilloscopes ever produced. The two represented below are well over 20 years old and are both still working excellent.

Analog Type Oscilloscope
Digital Storage Oscilloscope

I will get into the what does an Oscilloscope do in greater depth later. For now, don’t be intimidated by the looks of the Oscilloscope. It is an amazing diagnostic tool that is more relevant today than ever before. For now, just think of it as a graphical display of volts peak over time.

Please Come back for more great lessons on the amazing Oscilloscope!