OpenSpand is the most comprehensive extension to the TS1000 and ZX81 available to date.
Even though I've been selling ZX81/TS1000 composite video adaptors on for more than three years now, I love that OpenSpand provides clear composite video output with a back porch, and you don't need to modify your ZX81 / TS1000.
OpenSpand is a mature open source project created by Swedish vintage computer enthusiast Adam Klotsblixt. Comprehensive project documentation includes the design as a KiCAD project and an excellent User Manual. Adam also documented much about OpenSpand on HACKADAY.IO if you want more details.
The units being sold here are manufactured and supported in the United States and will be shipped with links to the manufacturer's support website in the U.S. These units were recently demonstrated at the Vintage Computer Festival Mid-West in Schaumburg Illinois.
The photos above show:1- The unit in its 3D-Printed Case2 - A top view of the component side of the printed circuit board assembly3 - A tilted view of the OpenSpand showing its various modules and components4 - OpenSpand on a ZX81 with composite video monitor, joystick, and external powered speaker5 - Diagram showing OpenSpand connectivity.
OpenSpand is based on the Olimex PICO2-XXL RP22350B-based development board. New releases of the OpenSpand firmware can be download to your PC from the project repository oncodeberg.org. You can then open the OpenSpand case and load it into the OpenSpand processor with a USB-C cable.
OpenSpand supports various Hi-Res graphics modes and is backwards compatible with ZXPAND.
If you any questions, message me.
You will love using your ZX81 / TS1000 with OpenSpand!