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Timex Sinclair User Group Meeting — January 2, 2023

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David Anderson, Adam Trionfo, Ryan Gray, Carl Miles, Stewart Newfeld, Paul Anderson, Greg, Tim Swenson, Tim Horner, Gustavo, Jeff Burrell, Mark

The first meeting of 2023 opened with a tribute to Bob Swoger, who passed away shortly after the December 18 meeting; David recapped Bob's roughly twelve years keeping the community alive through Sir Clive Alive and his later work with the Glenside Color Computer Club.

Ryan Gray demoed a TS2068 BASIC calendar program he rebuilt over the holiday break. He showed how to capture printer output from Fuse (the Free Unix Spectrum Emulator) by enabling ZX Printer emulation, harvesting the PBM file, and stitching pages together with ImageMagick. The calendar core code was lifted from the Fort Worth user-group library tape, combined with a recovered double-height font and a new "tiny dates" font built on top of the TASWIDE 64-column technique. That led into a discussion of TASWIDE itself (the print engine from Tasword, with a 2068-specific variant David has now re-hosted with Ryan's recovered copy), Zebra's old Tech Draw Junior (written by Jeff Street), and the practical problem of porting Spectrum machine code to the 2068 around the X-ROM and the ROM-call mapping tables that once circulated via the third-party programmer's guide.

Greg demonstrated WRX high-res graphics on a ZX81 — first a Petsky-style maze using two redefined slash characters, then a two-character Intellivision "running man" animation — running under the EightyOne emulator. The group walked through what WRX actually is (Wilf Richter's trick of mapping RAM into the 8K–16K window between ROM and RAM), its limit of about 25 user-definable characters, and the lineage back to Fred Nachbauer's SCRAM board and the Radio-Electronics Hunter board. Stuart followed up on Trevor Jacobs's 32K upgrade board, which decodes that same 8K window so WRX-style graphics work cleanly; populated boards should be available for around four dollars once ICs arrive.

A ZX81-repair thread tied much of the meeting together: Stuart shipped Carl a care package (period rub-out/delete membranes, German tactile keyboards, composite-video upgrade modules, RAM chips) so Carl can build Adam a working machine. The remaining bottleneck is ULAs — Charlie Ingley's New Zealand replacement (which also bundles 32K of RAM) is now the standard fix at about $35 plus shipping; Stuart and Paul have units in hand or in transit. Gustavo and Carl compared the US SCLD with the Portuguese TC2068's chip (RGB plus a bright pin for sixteen colors versus the US YUV/seven-color output), noting that no SCLD spares exist beyond a long-ago CATS bulk order from Portugal. Claudius in Poland has designed both a 2068 replacement board and an SCLD replacement; Jeff Burrell reported his own FPGA work already handles the missing bright signal and is waiting on PCBs. Mark closed the technical content by showing that ChatGPT will write working SuperBASIC for the QL and Sinclair BASIC for the Spectrum, but refuses TS2068 BASIC "because not enough units were sold." David announced a shared Google Sheet for planning future agendas, a planned set of beginner/FAQ pages on his site, and Tim Swenson tentatively booked for a future QL demo. Next meeting: Sunday, January 15, 2 PM Eastern.

Highlights

  • Tribute to Bob Swoger, who kept Sir Clive Alive going for ~12 years and passed away just after the Dec 18 meeting.
  • Ryan Gray demoed a recovered/rebuilt TS2068 BASIC calendar, printing via Fuse's ZX Printer emulation and ImageMagick.
  • Greg ran WRX high-res graphics on the ZX81 (Petsky-maze and Intellivision-style running man) under the EightyOne emulator.
  • Stuart shipped Carl a care package of keyboards, video mods, and RAM chips to build Adam a working ZX81; remaining gap is ULAs.
  • Charlie Ingley's NZ ZX81 ULA replacement (~$35, includes 32K RAM) is now the standard fix; Polish Claudius has a 2068 SCLD replacement, and Jeff Burrell's FPGA already handles the missing bright signal.

Projects discussed: FPGA "Advanced 2068" · Library Tape Archiving Process Topics: TS1000 / ZX81 / TS1500 · TS2068 / TC2068 · Repair & restoration · Hardware projects & new boards · BASIC programming · Video upgrades (composite, RGB, HDMI)

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