Electronic enthusiasts searching for a project to keep them busy this weekend, may be interested in a super cheap DIY Raspberry Pi oscilloscope published to GitHub website called Scoppy. The super affordable oscilloscope consists of an Android application combined with a Raspberry Pi Pico microcontroller and firmware.
The Raspberry Pi powered oscilloscope uses signals measured by the Pico and displays the waveforms on the Android device. No programming is required and both the application and firmware are now free to download from GitHub tutorial page. The Scoppy oscilloscope has been created to provide those learning about electronics and ultra-affordable oscilloscope that is useful for viewing low voltage low-frequency signals.
To build your very own Raspberry Pi oscilloscope you will need an Android device capable of running Android version 6.0 (Marshmallow) or higher. The Android device must also support USB OTG (On-The-Go) “most modern phones/tablets do (if you don’t see the app when browsing the Play Store then your device probably doesn’t support this feature)” says the GitHub tutorial page. Together with a Raspberry Pi Pico microcontroller and a USB OTG adapter/cable compatible with your phone/tablet.
“As you would expect, the specifications are rather limited, capturing a maximum of 100 kpts at a speed of 500 kS/s shared between the two channels. Without some additional front end circuitry to protect the Pico, the input voltage is limited to 0-3.3 V. Neither the app nor the firmware is open source, and getting access to the second channel and removing ads requires a ~$3 in-app purchase. Even so, we can still think of plenty of practical uses for a ~$7 oscilloscope. If you do decide to add some front-end circuitry to change to voltage range, you can set them in the app, and switch between them by pulling certain GPIO pins high or low. The app has most of the basic oscilloscope features covered, continuous and single shot capture, adjustable trigger settings and a scalable waveform display.”
For full instructions on how to build your very own ultra-affordable Raspberry Pi oscilloscope jump over to the Scoppy Github page by following the link below.