Modems, serial & RS-232
Modems, RS-232/serial ports, terminals, BBS access, VoIP-with-modems, and the Timex 2050 modem.
61 threads · 625 messages · 2001-12-21 → 2026-10-12
The Westridge/Timex 2050 modem connects the two eras of this topic. In the Yahoo years members mainly wanted documentation and a serial port. Robert Allen Turner asked for 2050 specs in 2002 so he could build a compatible serial port. Louis Florit hosted the "WC2050 Serial Conversion Hack" instructions on timexsinclair.org, and in 2003 Senen Racki uploaded a modem schematic to the group's files after Stephen Wenzler asked how to restore one or strip it down to a plain RS-232 board. In 2007 Bruno (zxbruno) asked whether the 2050, the Byte-Back modem or the Prism VTX-5000 had any modern use. The consensus was that they were mostly collectibles, though Louis wanted to run a 2068 BBS on the internet through a host PC. Bruno and Johnny Red then worked to preserve the TS1000 side of the Smart Terminal tape (Fred noted that ZX81 software belongs in .p files rather than TZX). In the 2008 "average age" thread, Senen recalled sending programs over phone lines at tape speed (2400 bps) without any modem, but that thread was mostly nostalgia.
The groups.io era made this practical work. Mike Druckenmiller designed a 6850-based serial card on ports 126/127 and ordered 10 boards in June 2023, but version 1 was "busted": the riser was too short to fit under the 2068's cover. Its BASIC test code also led to the bit-testing thread. Ryan Gray pointed out that the TS2060 spec planned channel-based serial ("T"/"B") and parallel ("C"/"G") interfaces modelled on the Interface 1. The group concluded that the 2068's joystick ports are input-only behind diodes rather than wired straight to the AY, so bit-banged serial through them is limited. Adam Trionfo's 84-message VoIP thread followed his attempt to get a landline for BBS calling and branched into tape-recovery advice and Jon's PicoWifiModem, which he used to reach the Magnum BBS over telnet. A Telnet BBS Guide search for "Baud Day" 2024 turned up Sinclair-specific BBSes.
From 2023 the 2050 itself became a project. Carl Miles showed a rare unit with an actual "Timex Sinclair 2050" label (David Anderson updated the timexsinclair.com page so Wikipedia could cite it), and 2050s from the Bill Miller collection were passed around for restoration and serial conversion. In 2025 David confirmed that a 4-pin RS232-to-TTL module can be wired straight to the 8251's RX/TX pins (3 and 19) without removing the dial circuitry. Other routes followed: Jorge Castillo's Wi-Fi modem through the joystick port with Microterm (shared by Ricardo Calcagno and built by Argentine members), Jon's study of ZX Interface 1 RS-232 compatibility for a possible TS-Pico expansion, and Carl's 2025 Interface 1 clone ("Interface Zero") with a network/RS-232 daughterboard, where Jeff Burrell warned that IF1 system variables clash with the 2068's. Willie Jones and Paul Holmgren, authors of the ISTUG BBS, joined the list and offered the 2068 BBS code. Several threads only drifted here: the ABQ meeting minutes (Carl's repainted 2050), the HAM-license thread (Argentine radio broadcasts of Spectrum programs), Senen's surplus COM210/COM220 Hayes modems, and the "Long Shot" identification of an MSD Commodore RS-232 adapter.
Key threads
- Timex 2050 Modem and Serial Port Conversion (#154 on groups.io) — The long-running groups.io project to restore 2050 modems and convert them into serial ports, ending with the 8251 RX/TX wiring answer.
- Modems and Voice-Over-IP Lines (#701 on groups.io) — Adam Trionfo's attempt to get a phone line for BBS calling, which grew into Wi-Fi modem and serial-to-telnet experiments.
- Serial Port Cards for TS2068 - 10 Ordered (#977 on groups.io) — Mike Druckenmiller's 6850-based serial card design and its first board run.
- TS2068 Serial Port Cards - Busted (#973 on groups.io) — The first serial cards' fit problems and the discussion of using the joystick/AY port for serial.
- TS2060 parallel and serial interfaces (#880 on groups.io) — How Timex planned to expose serial and parallel I/O through BASIC channels, following the Interface 1 model.
- Timex/Sinclair 2050 Modem with actual TS2050 Label (#831 on groups.io) — Proof that Timex-badged 2050s exist, plus Smart Terminal software and manual archives.
- Westridge TS-2050 Modem (#2342 on groups.io) — The 2002 Yahoo-era request for 2050 specs, answered with the serial conversion hack instructions.
- TS-2050 modem (#2279 on groups.io) — The 2003 search for the 2050 schematic, which Senen Racki eventually uploaded to the group's files.
- Wifi modem for TS-2068 via joystick port (#519 on groups.io) — Jorge Castillo's joystick-port Wi-Fi modem and Microterm terminal software.
- First steps in getting Microdrives running on a TS2068... (#210 on groups.io) — Carl Miles' Interface 1 clone with a network/RS-232 daughterboard, and the system-variable conflict it runs into.
All threads (61)
↳ marks a thread where this topic begins mid-conversation — the link jumps to the message where it starts.
| Thread | Msgs | Activity | Started by |
|---|---|---|---|
| ⭐ Modems and Voice-Over-IP Lines 📎 | 84 💬 | 2024-03-12 | Adam Trionfo |
| ⭐ Timex 2050 Modem and Serial Port Conversion 📎 | 53 💬 | 2026-02-10 | Adam Trionfo |
| ⭐ ABQ User Group Meeting - Sat. Feb. 3, 2024 📎 | 40 💬 | 2024-02-08 | Adam Trionfo |
| ⭐ TS2060 parallel and serial interfaces ↳ #4541 📎 | 29 💬 | 2023-10-24 | David Anderson |
| ⭐ First steps in getting Microdrives running on a TS2068... 📎 | 27 💬 | 2025-11-09 | Carl Miles |
| ⭐ How to do Binary Comparison (BIT Test) in Timex Basic 📎 | 22 💬 | 2023-07-26 | kevin.personal |
| ⭐ Serial Port Cards for TS2068 - 10 Ordered 📎 | 22 💬 | 2023-06-20 | Michael A. Druckenmiller |
| ⭐ TS2068 Serial Port Cards - Busted 📎 | 16 💬 | 2023-06-22 | Michael A. Druckenmiller |
| ⭐ Timex/Sinclair 2050 Modem with actual TS2050 Label 📎 | 14 💬 | 2023-12-03 | David Anderson |
| ⭐ Westridge TS-2050 Modem | 12 💬 | 2002-09-16 | Robert "The R.A.T." Alle |
| ⭐ Investigating the Spectrum's RS232 Interface (ZX Interface 1), for a potential 2 📎 | 12 💬 | 2024-03-14 | Jon |
| ⭐ TS-2050 modem | 12 💬 | 2003-10-07 | Stephen Wenzler |
| ⭐ Wifi modem for TS-2068 via joystick port 📎 | 10 💬 | 2024-10-23 | Ricardo Calcagno |
| ⭐ My guess..... ↳ | 8 💬 | 2003-11-09 | Stephen Wenzler |
| ⭐ Serial Port Works 📎 | 7 💬 | 2023-07-18 | kevin.personal |
| ⭐ MTERM manuals 📎 | 5 💬 | 2021-12-10 | François Lanciault |
| ⭐ WC2050 Hack to convert to serial port... | 2 💬 | 2003-08-28 | Louis Florit |
| ⭐ 2050 schematics | 1 💬 | 2003-10-03 | Stephen Wenzler |
| Average age of group members | 26 💬 | 2008-01-31 | Bill Loguidice |
| HAM License? 📎 | 22 💬 | 2024-01-30 | Adam Trionfo |
| Oliger Public Domain disks ↳ | 16 💬 | 2008-12-30 | Paul Anderson |
| Those who have the cassette that came with the TS2050 | 14 💬 | 2009-04-09 | zxbruno |
| Regarding the TS2050 and other Sinclair modems | 14 💬 | 2007-08-02 | zxbruno |
| COM210: Telephone Modem 📎 | 11 💬 | 2023-08-14 | Senen Rački |
| "Baud Day" Celebration on 3/12/24 📎 | 11 💬 | 2024-04-01 | Adam Trionfo |
| New Member 📎 | 11 💬 | 2021-08-04 | willie46151 |
| Long Shot… 📎 | 10 💬 | 2023-09-27 | David Anderson |
| Ebay auction ↳ | 9 💬 | 2002-09-14 | Louis Florit |
| Spectrum Terminal 📎 | 8 💬 | 2024-01-17 | Adam Trionfo |
| rtty | 7 💬 | 2012-01-11 | Billiam |
| Westridge 2050 Modems 📎 | 7 💬 | 2024-02-26 | Paulo Leite |
| TS 2068 RS-232 output from joystick port details 📎 | 6 💬 | 2024-01-17 | qwertyfan2000 |
| Using the TS2068 as a terminal to telehack... (through ts-pico?) 📎 | 6 💬 | 2026-01-26 | David Anderson |
| "Z-Term 64" Terminal Program 📎 | 6 💬 | 2024-02-06 | Adam Trionfo |
| Byte-Back BB-1 or BB-68 | 5 💬 | 2016-11-17 | Dan Schenk |
| RS232/wifi 📎 | 4 💬 | 2021-12-21 | David Anderson |
| Timex Sinclair and the internet | 4 💬 | 2008-12-13 | rockbobster2mars |
| BBS Newsletters Archive Progress | 4 💬 | 2024-02-12 | David Anderson |
| Good Morning - Where's my head at | 3 💬 | 2023-08-22 | David Anderson |
| Westride 2050 modem 📎 | 3 💬 | 2023-04-21 | John Mobley |
| Phone Line Simulators | 3 💬 | 2024-09-10 | SuperMikeNJ |
| Regarding the TS2050 and other Sinclair modems (Ethernet/TS2068) | 3 💬 | 2007-08-08 | kb0oyz |
| "Sinclair Survival" and ""Across the Pond" Timex Columns | 3 💬 | 2024-02-13 | Adam Trionfo |
| wifi modem is getting there 📎 | 2 💬 | 2026-10-12 | ArcadeDanger Danger |
| 115200bps in Timex FDD 3000? | 2 💬 | 2004-12-22 | Jarek Adamski |
| a bit of modem history | 2 💬 | 2024-03-18 | Paul Holmgren |
| 2050 Modem Boards | 2 💬 | 2011-08-24 | pxx1_2000_32724 |
| User Manual for Timex Sinclair 2050 Telecommunications Modem | 2 💬 | 2007-07-28 | george.orr1 |
| VOIP | 2 💬 | 2005-04-09 | Eric Johnson |
| Network interface on 8251 USART | 1 💬 | 2006-04-05 | Jarek Adamski |
| TS 2068 Twister and Z-Link | 1 💬 | 2002-07-20 | Abed Kahale |
| ISTUG TS2068 BBS | 1 💬 | 2024-09-10 | Adam Trionfo |
| potential topic for hardware folks to explore | 1 💬 | 2024-03-10 | Paul Holmgren |
| RS232 Interface | 1 💬 | 2001-12-21 | rgschimke |
| 2023-06-27 Serial Port Update | 1 💬 | 2023-06-27 | Michael A. Druckenmiller |
| MTerm II available | 1 💬 | 2024-02-14 | David Anderson |
| IPv4 Subnetting | 6 💬 | 2010-07-15 | pxx1_2000_32724 |
| BYTE-BACK MODEM @ EBAY 📎 | 4 💬 | 2024-09-27 | Luis D'Ardis. |
| 2050 modem to rs232 zebra kit | 2 💬 | 2022-01-18 | Willie Jones |
| Terminal Emulator Idea | 1 💬 | 2023-09-18 | John Mobley |
| phones | 1 💬 | 2024-01-03 | larry lorenson |