PC based CRO

http://vanangamudiyan.blogspot.com/2011/06/pc-based-cro.html

As we are Electronic engineers, the necessity of Measurement systems becomes in-ignorable. Especially CRO is an essential equipment when analyzing different signal processing systems like communication systems. CRO cost is much higher when compared to DMM. So utilising the digital nature of DMM, why can’t we connect it to our PC ( a much powerful digital system that can handle wide range of signals ). The advantages include we can record the measured values since we have huge amount of HDD space, and no need of storage CRO.

Principle:

DMM measures the voltage or current level at an instant. If it is connected to computer, the measured values can be recorded at very high sampling rate. Using an Software or by creating our own Software we can plot the values and manipulate or analyze the system.

I’ve already planned to create a system with multiple processor ( for specific function ) dedicated to simulation with our own OS. But my experience is not enough. So after completing this PC based CRO. I’ll move towards it. Can anybody help me.

Revision - originally was a separate blog post

http://vanangamudiyan.blogspot.com/2011/06/pc-based-cro-revision-i.html I planned to build ’PC Based CRO’. But it can be done with DMM circuitry, due to it’s sampling disadvantage, i.e it sampling rate too low, it is not suitable for CRO (by Nyquist Theorem).

I googled for “PC Based CRO”, most of the projects use the sound card as the cheap ADC.It’s frequency range is limited to AF band. I’m now collecting information on fast ADC’s, for the project. After learning the circuitry and working of ADC’s and its practical implementation, Project will continue. I’m currently working on Arduino. So I’ll try to incorporate it to my project. I’m preparing a Tutorial Series on Arduino for Robotics Beginners.

Abbreviations

CRO - Cathode Ray Oscilloscope. DMM- Digital Multi-Meter. HDD - Hard Disk Drive. OS - Operating System. PC - Personal Computer.