The Scoppy Oscilloscope project (https://oscilloscope.fhdm.xyz/) is a very cool 2MS/s Raspberry Pi Pico based oscilloscope for Android devices, but it requires a "front end" to read voltages outside the 0-3.3V range of the Pi Pico.

This is my version of a (mostly) through-hole board for my students to build a front end for Scoppy. The few SMT components are SOIC, so can be hand soldered if needed.

I chose to make the components through-hole so that the end user could easily modify them with commonly available parts to adjust the voltage ranges... the Scoppy firmware and Android App makes this very easy to do.

To play with a simulated version of the Channel 2 input on this board, check out: https://tinyurl.com/2n5plwrj (Falstad's Circuit simulator is awesome!)

The project designer sells both kits of their own design, and a fully assembled version of their board at https://store.fhdm.xyz/dso-500k If you're just looking to get up and running with Scoppy in the most efficient manner, I suggest purchasing one of these boards rather than assembling this design!

But if you want copies of the board that I'm using with my students in the BCIT Technology Teacher Education Program, then this is where to find them!