DesignSpark Electrical Logolinkedin
Menu Search
Ask a Question

3 Sep 2018, 8:10

RS Pro DSO entry: Use of Oscilloscope

While the DMM is my favourite instrument, allowing me to measure many things whether static, slow-moving or repetitive.  My Fluke 117 is a capable DMM allowing me to measure AC and DC voltages as well as Frequency, capacitance and more.  However, anytime the signal gets above 3 to 5 Hertz, an oscilloscope is needed.  There are low priced alternatives such as the Digelent Analog Discovery 2, which requires a computer attached to control and display the results, making the setup more awkward than a stand-alone instrument.

At this point in time, I am working on the Raspberry Pi small computers and adding external sensors to it, which requires me to be able to see the resulting waveforms generated from the Python code.  In this case, a scope with a single sweep capture is required, since a write or read is a short sequence usually happening once per time.   When writing or reading a specific protocol, an oscilloscope that can decode the protocol (such as I2C or One Wire) is quite useful.

Having started learning oscilloscopes with the venerable Tektronix 454, the modern DSOs are so much easier to capture a single sweep than the old way of using Polaroid film and a hood to take photos of a single sweep.  Analog gave way to digital, giving us single sweep, however one now needs to be aware of undersampling of the waveform as well as just looking at the trace on the screen.

In summary, while a DMM is a very useful instrument for engineers, an oscilloscope is required for when the engineer needs to see what's happening in the milli- to picosecond frequency world.


3 Sep 2018, 8:10