TSU Meeting MONDAY — January 5, 2026

David Anderson, Jeff Burrell, Carl Miles, Adam Trionfo, Ryan Gray, Joseph, Jack, Gustavo (LU1AU), Mowgli

The group opened with VCF planning for 2026 — David asked attendees to RSVP to his coordination email and confirmed VCF Midwest's Renaissance hotel block had just opened, with David, Carl, Joseph, Jeff and Mowgli all leaning toward Midwest and David also planning VCF East in Wall, NJ. The group discussed pooling tables again and trying to be seated together this year. Newcomer Jack gave his origin story: a 1982 ZX81 he rebuilt into an old terminal keyboard and a RAM pack expanded to 64K, then a TS2068 with floppy drive used at his church for a cassette-labeling database. He is shipping a box of QZX (ham-radio Sinclair) newsletters to the archive, prompting a long tangent on amateur radio — David announced his own plan to finally get licensed this year, and Gustavo (LU1AU, Argentina) described cloning a TNC 220 packet-radio controller for the TS2068 with an 8251 SCC, used to exchange programs over HF AX.25 with friends in Buenos Aires.

Adam showed off the ZX Spectrum Next he bought from Joseph and a new print-on-demand book by Simon Goodwin. The group worked through what makes the Next interesting — FPGA-based hardware-accurate Spectrum, multiple selectable "personalities" including TC2048 (with the SCLD 64- and 80-column screen modes), CP/M 3, and switchable CPU speeds up to 28 MHz. Gustavo asked whether the Next's CP/M BIOS source or binary is available, with a view to building a compatible disk reader/writer. The conversation moved to the Next's open-source hardware and its clones, particularly the N-Go (fits a modified 48K Spectrum case, optional acrylic case with mechanical-switch keyboard, ~€270) and the X-Berry Pi; Ryan was nominated to buy an N-Go and report back. Adam lamented the absence of a true TS2068 core for the Next or for MiSTer.

Jeff introduced the Jupiter Ace, prompted by a 35th- (and 40th-) anniversary reprint of the Vickers/Altwasser book. He's planning a hardware build rather than using existing emulators (Minstrel, EightyOne) — a Z80 paired with a Pi Pico or ESP32 to handle memory decoding and video generation, with the goal of really understanding the Ace's contention-based partial-decoding scheme. The group noted Forth's use in Lucasfilm's motion-control cameras and the Ace's 3K RAM, redefinable character RAM, and roughly 5,000 units sold.

Joseph gave an extended deep dive on Eastern-Bloc Sinclair clones, walking through his own Didactic Gamma (1987–88 Czechoslovak ZX Spectrum clone using a genuine Ferranti ULA-7 with Eastern Z80 and RAM, 80K via custom bank switching, three reset/power/bank buttons) and its successor the Didactic M (cheapened, Soviet ULA, RGB instead of YUV). He covered the MB02/MB03 disk system by Slovamir Lapsky — Z80 DMA, half-meg battery-backed RAM, fast enough for floppy-streamed animation and capable of doing per-line attributes Timex-style — and an interlaced demo Lapsky did for the TC2068. He also recalled meeting Frantisek "Fuksoft" Fuka, the Czech ZX games author/translator (Indiana Jones text adventures, Tetris 2, FIRE, AY music ports of Driller). Finally, Carl reported he'd received composite-video boards from Stewart for Mowgli's two TS1500s (replacing his earlier transistor mod, which was too dim), finished a keyboard swap on Ryan's NTSC-converted ZX Spectrum, and is testing a prototype ZX81 USB keyboard Stewart sent him. Next meeting is Sunday January 18 at 2 PM, with possibly Brett (Australia) joining to talk about his YouTube deep dives into Soviet clones.

Highlights

Jack joined as a newcomer and is donating a box of QZX (ham-radio Sinclair) newsletters to the archive
VCF Midwest hotel block opened; Midwest is the consensus destination, David also doing VCF East
Adam demoed his ZX Spectrum Next (bought from Joseph) — TC2048 modes, CP/M 3, switchable CPU speed
Jeff is building a Jupiter Ace hardware clone: Z80 + Pi Pico/ESP32 for memory decoding and video
Joseph gave an extended history of the Czechoslovak Didactic Gamma/M Spectrum clones and the MB02/MB03 disk system

Topics: ZX Spectrum · Pico / modern interfaces (UnoDos, etc.) · TS1000 / ZX81 / TS1500 · User group meetings & events · Prototypes & rarities · Modems, serial & RS-232

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