A full TZXDuino build from Zaxon’s kit, including the V1 board fix, Arduino IDE and library setup, the old bootloader gotcha, and loading games on a ZX Spectrum.
Building an Epyx FastLoad cartridge for the Commodore 64, working around remarked AliExpress EPROMs, and timing SD2IEC loads with and without it.
The Kung Fu Flash is Kim Jørgensen’s open source cartridge emulator for the Commodore 64, sold ready made by The Future Was 8 Bit. I open it up, test disk, PRG and CRT files, and update the firmware.
The ElCheapoSD from BennVenn puts your Atari Lynx library on an SD card. I set it up, test games on a Lynx II and explain how to avoid bricking it.
I set up and test the TerraOnion Super SD System 3, which plays PC Engine HuCard and CD-ROM2 images from SD card, and find out whether it is a buggy mess.