TSU Meeting MONDAY — March 31, 2025

David, Carl Miles, Ingo, Sam, Stuart, Tim, Jeff, Joe, Peyton, Ryan Gray, Christian, Mike, Adam, Johnny Red

An off-schedule Monday meeting (moved off Easter week) anchored by two big strands: the new TS1000-replacement motherboard Carl Miles and Ingo are co-developing, and VCF Midwest planning. Carl walked through the prototype board behind him — an early eight-layer design currently out at JLCPCB — that crams an integrated WESPY (ESP32 Wi-Fi loader with fast loader and save), a battery-backed 512K×8 RAM with bank-switching plans, the M1-NOT circuit on a 7400, and a Tim Cook-style joystick port (a known three-chip design with two GALs and a 2K SRAM, redefining keys via a small machine-code routine) onto the original TS1000 board footprint. All the I/O (VGA, composite, audio, 9V power) is consolidated onto a single DB9 to keep the back edge free for the original case; Ingo's brother is 3D-modeling a Kilo-Zed case and eventually a TS2068-sized case for an extended variant. The group discussed dropping the mask ROM for a flash chip so multiple ROM images (4th, Jupiter Ace, Spectrum-ish) could be switchable, sourcing ULAs (Stuart offered a care kit of ULAs/ROMs/feet; longer term, talking to Charlie about bare CPLD ULA dies), and using surface-mount + JLCPCB assembly rather than hand-kitting parts.

Sam reported on a motherboard-variant survey of US TS1000/ZX81 units: only ~5 data points so far, but the ULA versions (1-84E, 2-10E, an earlier 1-5x) and ROM revisions (650 with the math bug, 622 fix, final 649) are printed on the chips and worth crowdsourcing. A side rabbit-hole through eBay serial-number photos turned up TS1000s made in France (B-prefix facility near Switzerland) and even one made in the UK, on top of the expected Portugal builds — news to the group. Sam asked members to crack open spare units and report issue number, ULA, ROM, chip count, and back-cover color. Stuart added trivia about the NFI (Name Plates for Industry) shell molders and how the channel 2/3 switch hole was filled during spray-paint and knocked out at the factory afterward.

VCF Midwest planning: the Schaumburg hotel block is filling fast (Ingo had to call to get a room and apply the group rate); VCF has not yet opened table booking, and David will call an emergency Zoom to coordinate when tables open. Confirmed attendees so far include David (2 tables, kit components + books + ZX printer driven by Tim's Arduino adapter), Carl, Ingo, Joe, Jeff K. (flying in, no hardware), Peyton (helping at tables), and Stuart. The group plans a shared spreadsheet to avoid duplicate hardware and discussed showing demos on shared machines (David and Carl both have WESPY-equipped units).

Shorter items: Tim's TS2068 ZX BASIC port is functionally complete except for LOAD/SAVE in the EX-ROM, which is waiting on "our man in Argentina" (Johnny Red). Ryan Gray posted what he calls a notionally final version of his Time Sink font and a quick adjustment of the built-in font, and is poking at the ROM to see whether ZX81 BASIC's integer-in-float packing could speed up array indexing. Christian floated burning programs to audio CD as a tape replacement — the group noted the Spectrum and C64 communities had done this in the '90s, but Carl pointed out the WESPY makes it moot. David closed with a reflection on the meetings as the modern equivalent of in-person user groups, and on the recordings being a resource for future users.

Highlights

Carl & Ingo unveiled a new TS1000-replacement motherboard prototype — 8-layer, ESP32 WESPY + joystick + 512K RAM + DB9 breakout, currently at JLCPCB
Sam's motherboard-variant survey turned up TS1000s made in France and the UK, not just Portugal — group asked to crack open spares and report ULA/ROM/issue/color
VCF Midwest planning: Schaumburg hotel filling fast, tables not yet open, David will call an emergency Zoom when they are; shared spreadsheet for who's bringing what
Ryan Gray posted a notionally final version of his Time Sink font and is investigating integer-in-float packing for faster ZX81 BASIC array indexing
Stuart offered Carl a care kit of ULAs, ROMs, and rubber feet for the new board; longer term, the group may approach Charlie for bare CPLD ULAs

Projects discussed: "1068" — Enhanced TS1000 · ZX-Wespi / Wespi-Nano Topics: TS1000 / ZX81 / TS1500 · Hardware projects & new boards · Pico / modern interfaces (UnoDos, etc.) · User group meetings & events · Video upgrades (composite, RGB, HDMI) · BASIC programming

Summary generated from the meeting recording; the full transcript is kept in the group's private archive.