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TSU Meeting MONDAY — June 1, 2026

David Anderson, Charlie Day, David Lafinier, Tim Swenson, Jeff Coleman, Jeff Burrell, Gustavo, Joe, Ryan, Paul Anderson, Michael Kutzner

The Monday meeting opened with Jeff Coleman's recap of VCF Southwest, where he ran two Timex/Sinclair tables. A walk-up donor brought in a box of Timex hardware, and the group's Bill Miller fund was used (jointly with Tim Swenson and Adam Trionfo's coordination) to acquire it for preservation. One of the D&D Software founders brought a TS-1500 with Z-Expander and demoed Zoust and a Robotron port over a wireless D-pad on a 5‑inch B&W TV; the Spectrum Next on the table couldn't load its Spectrum personality from SD, so it stayed on static display. Cocoa and Commodore 64 collectors came by interested in porting Jeff's Baudot-keyboard project to their platforms.

Two new members were introduced. Charlie Day was active in the North Carolina Triangle TS user group in the 1980s, wrote software that Hogwild Software picked up (he traded it for QL software), and is now running his old listings in Fuse on Linux — a small windowing system in BASIC that pages between memory banks. David Lafinier (founder of the Florida Retro Computer Club, ~80 machines, broadly retro but new to Timex) described frying his TS2068 by hooking a DivMMC directly to the edge connector without a Twister board, and is now repairing a donor 2068 Paul Anderson sent him.

The group helped David troubleshoot the damaged 2068. Stable copyright text plus flashing black blocks pointed away from the SCLD and toward the lower 16K video RAM (U6/U7) or lifted/damaged traces around it. Joe confirmed he has seen the same symptom from RAM failure many times. Discussion covered the two RAM speed variants on the schematic (4416), the need for a diagnostic ROM (Carl Miles wrote one as a teen for a pallet of 2068s but the source was never recovered; the Spectrum diagnostic ROM on the TS‑Pico image is the current substitute), and the Twister board's switchable Spectrum ROM for running DivMMC under a Spectrum personality — in native 2068 mode the TS‑Pico is the practical storage solution.

David Anderson then walked through the TS‑Pico (Ricardo Calcagno's hardware, Gustavo's ROM-side command protocol carried over from his 1980s CP/M extension, Ryan's ongoing software work) and showed his prototype Raspberry Pi Pico replacement for the 8251 UART in the West Ridge 2050 modem — emulating the 8251 at the original port addresses so existing terminals like ZXTerm80 work unchanged, with a 74LVC245 for 5V/3.3V level shifting and a 'noisy' ZIModem (ESP32 with dial tone/busy/connect audio) as the back end; he hopes to reprogram the UART divisor to push 300 baud to 1200. Charlie showed an unidentified Zebra serial-port add-on for the 2050 (the top isn't a UART socket as expected — Stewart Newfeld may be invited to a future meeting to explain) and a Paul Hunter battery-backed 8K NVRAM board from a 1983 Radio-Electronics article; David tied this to Fred Nachbaur's SCRAM and Wilf Rigter's WRX16 high-res graphics on the ZX81. The meeting closed with Ingo's keycap Kickstarter (David's low-profile ZX81 caps arrived, including 'function new line', 'function enter', delete/rub-out and a 'ZEDHED' bonus key), a preview of David's Open ZXpand build (50 PCBs in hand, RP2350-based reverse engineering of Charlie Robson's ZXpand for ZX81/1000), a tour of the Virtual OS Museum (Minerva/QDOS, Urs König's QL/E, SQLUX, Minix, Irix, Solaris) found via Slashdot, and a reminder that the next meeting is Sunday June 21 at 2pm.

Highlights

  • Bill Miller fund used at VCF Southwest to rescue another walk-up Timex donation for preservation
  • Two new attendees: Charlie Day (NC Triangle TSUG, Hogwild Software author) and David Lafinier (Florida Retro Computer Club)
  • Group diagnosed David's flashing-black TS2068 as lifted traces / U6–U7 video RAM, not SCLD failure
  • David Anderson demoed a Raspberry Pi Pico 8251 emulator for the West Ridge 2050 modem, paired with a noisy ZIModem ESP32
  • Ingo's ZX81 low-profile keycap Kickstarter shipped — includes function-enter, function-new-line, delete/rub-out and a 'ZEDHED' key

Projects discussed: TS-Pico · The Bill Miller Collection · Library Tape Archiving Process Topics: TS2068 / TC2068 · Repair & restoration · Pico / modern interfaces (UnoDos, etc.) · Modems, serial & RS-232 · TS1000 / ZX81 / TS1500 · User group meetings & events

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