First off, the disclaimer. I'm not an electronics expert - I'm at best a beginner. However, I can solder and I know what the various components do (within reason) so what's below is my best attempt at either making or modifying stuff.
These guides mainly deal with the PCB and associated bits, the enclosures are up to your tastes and abilities.
ISD1820 Lo-fi Sampler
Takes an ISD1820-based audio recording board, adds in pitch control and breaks out the record and playback controls to external buttons.
All work © Darren Shaw 2020 - 2021 (except where noted)