k. Modular oscilloscope for everyone
QUESTION:
I need a digital oscilloscope that connects to a PC, a tablet or a mobile phone. Are there any cheap options?
ANSWER:
The basic part of any digital oscilloscope is a quality analog to digital converter. The word “quality” incorporates the operating range as well as precision of different kind of measurements. The most important operating range data are: maximum frequency range of the sampled signal (ex. up to 60 MHz), voltage level range (ex. form +/- 30 V~; is adapter needed for high voltages, like 250 V~?), time base precision (how accurate are the frequency measurements)… There are also other factors that may influence ones decision for a particular product or technology. One of them is price. Digital oscilloscope module prices start at around 200 USD (Red Pitaya will be sold from 299 USD to 399 USD, depending on the oscilloscope module version), but not all products have the same performance.
If you need just a simple oscilloscope with operating range up to 1 MHz (1.000.000 samples per second) you may as well use a PC32 microcontroller as a key part of your home built oscilloscope. The price tag is just a few euros or dollars. Though it you won’t be able to measure high frequency signals, you would still be able achieve at least the same or a higher performance as an average multimeter with a graphical signal display.