Timex Sinclair User Group Meeting — August 8, 2022
David Anderson, Adam Trionfo, Tim Ward, Tim Horner, Tim Swenson, Willie Jones, Kevin Dorf, Carl Miles, Jeff Burrell, Ralph McCrum, Greg, Jay
A show-and-tell meeting opened with newcomer Tim Ward recounting his Timex/Sinclair history — starting the Fort Worth user group in 1983, working with Tony Willing on the Vashon Island (VISTA) group on the West Coast, mailing newsletters and selling cassette-tape software libraries, and being profiled with his TS gear in a 1993 Washington Post Magazine feature.
The technical core was hardware show-and-tell. Willie Jones demonstrated an eight-channel relay board driven from his TS2068, built with Tim Horner's redesigned circuit: a fully-decoded port-31 Kempston-style interface using the 688 comparator chip that collapsed the original nine-chip design down to two or three chips, plus a four-relay All Electronics module. Tim Horner also showed his USB-keyboard adapter board — a tiny SMD interface that lets a modern keyboard drive a ZX81 (with a debounce buffer, toggleable for game use, and per-game key mappings), though it doesn't yet work on the TS2068 because of SCLD logic-level differences. Kevin Dorf showed his new rainbow-PLA 3D-printed TS1000 case (from a Thingiverse ZX81 model he extended), a tactile micro-switch keyboard from Stewart Newfeld/Zebra, and an in-progress ZX-Wespi ESP32 install paired with a RedHawk composite-video mod, with discussion of the Wespi's fast tape-loader stub and Wi-Fi/.p-file loading. Jeff Burrell updated the group on his SD-card interface for the 2068 (CPLD glue logic plus Raspberry Pi Pico, dropping the FPGA): saving works, load support was a few days out.
Discussion ranged over ZX81 high-res techniques (the WRX RAM-pack modification, software-only pseudo-hi-res, the Memotech HRG and whether its ROM/schematic have been reverse-engineered), Dr. Beep's flicker-free 1K hi-res ZX81 games, and the annual 10-line BASIC contest. Ralph McCrum joined late and described his FDD-3000 + AmDisk setup, running CP/M on the 2068 via Nazir Pashtunyar's T-Doc twister adapter, with software 80-column drivers from Portugal and a serial modem to 19.2k — until lightning fried one of his FDD-3000s. Adam Trionfo demonstrated Scion's View 3D on real 2068 hardware (faster than expected; slices-based modeling; François's posted Imperial Walker scans were shown), and the group traded stories about professional uses of the machines: David Sully's Pascal payroll program for a pub owner, a Florida 2068 weather station that supplied National Weather Service hurricane data, Parker's TS1500-based HVAC controller for Carrier, and Art Colgate's TS2068-controlled three-axis milling machine running software written by Ray Kingsley (who the group believes has since passed away). Greg asked about a back-of-machine extender so his Z-Expand will clear the TS1500's awkward port shape; Willie offered to dig one out or design a small pass-through board.
Highlights
- Willie demoed an 8-channel TS2068 relay board; Tim Horner's redesign with the 688 comparator cut a 9-chip Kempston-decoded circuit down to 2–3 chips.
- Kevin showed a rainbow-PLA 3D-printed TS1000 case with tactile keyboard and an in-progress ZX-Wespi + composite-video build.
- Tim Horner's USB-keyboard adapter (with buffer + per-game key mapping) runs on the ZX81; the 2068 port is blocked on SCLD logic-level differences.
- Jeff Burrell's CPLD+Pico SD-card interface for the 2068 now saves files; load support is a few days away.
- Tim Swenson recounted a Florida TS2068 weather station whose data the National Weather Service used to fill a hurricane gap.
Projects discussed: ZX-Wespi / Wespi-Nano · UnoDos Topics: Hardware projects & new boards · Pico / modern interfaces (UnoDos, etc.) · TS1000 / ZX81 / TS1500 · Joysticks & controllers · Disk & floppy systems (Larken, AERCO, Oliger) · Utilities & applications
Summary generated from the meeting recording; the full transcript is kept in the group's private archive.