Kit of hardware components to build a customizable analog front end board, with header pins for use with your choice of Arduino Uno or STM32F103 Blue Pill (microcontroller boarde not included). Use your computer with the provided Python code to display captured signals and adjust settings. Requires a soldering iron and solder to assemble (and it wouldn't hurt to have some flux on hand).
This is not a commercial grade instrument but rather an educational kit. That said, if assembled well then you should find it to be quite a functional tool for low frequency signal capture.
Youtube: https://youtu.be/z2SUedz2vag
Not everyone needs an expensive oscilloscope for small hobby projects, but most other low cost solutions only support one channel and are difficult to customize. And building your own fully customizable oscilloscope is just plain fun!
This kit uses only commonly available through-hole components, making it easy to customize to your specific needs and easy to repair if you make a mistake. Two channels allow for comparison of signals in time (Which signal went high first? What was the signal state when the clock signal switched?). If you assemble as suggested with the provided components then the input impedance is approximately 1 MegOhm, so ordinary 1x/10x oscilloscope probes behave as expected. Generates a negative voltage rail from your single power supply, and allows a voltage offset to optionally be applied by turning on a digital pin, allowing you to process signals that go below their ground or to use the full range of your ADC for positive signals as needed. The circuit for each channel consists of a resistive-capacitive attenuator (approx 4:1 with provided suggested components), op amp voltage follower, and op amp voltage offset. Components may differ somewhat from those pictured.
This is supplied as a kit of parts. You will need a soldering iron and solder to assemble it. You will also need to supply an Arduino Uno or STM32 Blue Pill (and, in the latter case, the hardware to program it). You will need a USB cable with the appropriate connector for your microcontroller board to facilitate passing the collected data, and a computer running Python to display the results. Ideally you would have oscilloscope probes to connect the signals to the supplied BNC connectors, but you could instead solder some spare wire directly to the board or attach header sockets or whatever other connector suits your purpose. Seller has tried to make this kit as straightforward as possible. If you have trouble with it, please get in touch and I will try to provide basic technical support, but please also understand that ultimately this is a DIY kit and your individual results may vary.
This kit is for low-voltage use only. Exactly what signal range is appropriate will depend on how you customize it, but with the supplied suggested components the 4:1 attenuation would allow approximately 0 to 20V ( -10 to +10V with offset) using the 5V Arduino Uno or 0 to 13.2V ( -6.6 to +6.6V with offset) using the 3.3V STM32 Blue Pill.
See https://www.github.com/picosapiens/rospo for sample code. It is probably not bug free. Part of the tinkering experience :-)
This listing only ships to the United States. In other countries, you might wish to purchase the digital delivery version (also in my booth) and source all the parts yourself.