website/content/museum/timex-sinclair-1500.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
TIMEX / SINCLAIR 1500	Computers	Home Computer	U.S.A.	1983	Zilog Z80A	name image company company_name specs tabs forum_thread photos hardware links docs related oc_id source 1500 /media/museum/photos/timex_1500_system_s1.jpg /companies/timex-sinclair TIMEX / SINCLAIR label value NAME 1500 label value MANUFACTURER TIMEX / SINCLAIR label value TYPE Home Computer label value ORIGIN U.S.A. label value YEAR August 1983 label value BUILT IN LANGUAGE Sinclair Basic label value KEYBOARD Chicklet keyboard (ZX Spectrum style), 40 keys label value CPU Zilog Z80A label value SPEED 3.5 MHz label value RAM 16 KB label value ROM 8 KB label value TEXT MODES 32 columns x 24 lines (2 lines are reserved for system messages and commands) label value GRAPHIC MODES 64 x 44 dots label value COLORS Black and white label value SOUND None label value SIZE / WEIGHT 23 x 14,4 x 3 cm / 550g label value I/O PORTS Expansion bus (Z80 bus), tape interface, RF video output label value POWER SUPPLY 9V AC adaptor label value PERIPHERALS 16 KB RAM, printer + all the Sinclair ZX81 peripherals label value PRICE US $79.95 (USA, 1983) photos hardware links docs 625 title subtitle text image LARGE VIEW /media/museum/photos/timex_1500_system_s2.jpg title subtitle text image BOTH SIDES /media/museum/photos/timex_1500_sides_s1.jpg title subtitle text image KEYBOARD CLOSE-UP /media/museum/photos/timex_1500_keyboard_s1.jpg title subtitle text image REAR SIDE All of the Sinclair ZX-81 peripherals could be plugged into the expansion connector. /media/museum/photos/timex_1500_rearside_s1.jpg title subtitle text image TIMEX LABEL The Timex 1500 were made in Portugal by the Timex Portuguese subsidiary. /media/museum/photos/timex_1500_label_s1.jpg title subtitle text image RAM EXPANSION The Timex 1500 could be expanded up to 32 KB RAM thanks to a 16 KB expansion module (here a Sinclair model). However, some Poke commands had to be entered so that the computer regognizes the module. /media/museum/photos/timex_1500_rammodule_s1.jpg title subtitle text image INSIDE Like the ZX-81's, this mainboard holds only 5 chips, but with 16 KB of RAM. Two versions were actually produced, the first one had 8 x 4116 RAM chips instead of 2 x 4264. **(1)** UHF TV modulator\ **(2)** Keyboard connector. A second keyboard connector is located near the CPU\ **(3)** 16 KB RAM chips (2x4264)\ **(4)** Sinclair BASIC 8 KB ROM chip\ **(5)** Custom Timex chip made by NCR, in charge of... virtually everything! It deals with the keyboard, the tape recorder interface, the RAM & ROM management, the video and the expansion I/O port\ **(6)** Zilog Z80 processor\ **(7)** 5V power regulator with it heat sink, the black metal plate. /media/museum/photos/timex_1500_inside_s1.jpg title subtitle text image DISMANTLED Dismantling a Timex 1500 is quite easy, apart from the two fragile keyboard connectors which have to be gently disconnected and reconnected. /media/museum/photos/timex_1500_dismantled_s1.jpg title subtitle text image USER MANUAL This Timex 1500 was part of a 6-unit Basic programming course. Like other Sinclair and Timex user manuals, the Timex 1500's manual was very complete and detailed. /media/museum/photos/timex_1500_manual_s1.jpg title subtitle text image SUITCASE VERSION /media/museum/photos/timex-sinclair_1500_suitcase.jpg title subtitle text image TIMEX SINCLAIR 2020 Tape recorder /media/museum/hardware/timex_sinclair_2020_1.jpg title subtitle text image TIMEX SINCLAIR 2040 Printer The TS 2040 was the rebadged US version of the ZX Printer that could be connected to all of the Timex (and Sinclair ZX-QL) systems. It used the same thermal metallised paper rollers. LPRINT and LLIST commands redirected output to the printer. COPY did a screen dump. /media/museum/hardware/timex_1000_printer2040_1.jpg title subtitle text image TIMEX SINCLAIR 2040 Box /media/museum/hardware/timex_1000_printer2040_box_1.jpg title subtitle text image WESTRIDGE 2050 Modem The TS 2050 Telecommunications Modem was designed for Sinclair Research by Westridge Communications CIE. At the same period first deliveries of this modem should occur, Timex went out of the computer business. Westridge which then had a large stock of unsold modems decided to release them with the 'Westridge 2050' name. The modem was compatible with TS100, 1500 and 2068 models. A specific software was delivered for each model. It used an Intel 8251 USART chip with 300 baud capability through a direct connexion to a telephone socket. /media/museum/hardware/timex_2068_modem2050_1.jpg title subtitle text image TIMEX FDD 3000 Floppy Disk Drive The Timex FDD 3000 was a Full Computer made by Timex Portugal. It could also be used as a Floppy Drive System for ZX Spectrum, TC 2048 and Clones, including the Timex 2068.\ It featured:\ Z80 Processor\ 64 KB RAM\ 2 x Serial Ports\ 2 x 3" floppy Disk Drives As it was a full computer it allowed to run CPM on it with Timex Computers acting as a terminal, or it could act as a Floppy drive system that kept the ZX Spectrum or compatible computer free because of the FDD own processor and RAM.\ On 'floppy drive mode' user ran TOS (Timex Operating system). Thanks to **Jose Pina Coelho** for the pictures /media/museum/hardware/timex_2048_fdd3000_s1.jpg title url text Timex Computer World http://members.fortunecity.com/johnnyred/home.html Very interesting site, presenting all Timex computers. title url text TS1000.US http://www.ts1000.us/ "TS1000.US, a tribute to the most unique and powerful small computer ever built!"... with docs, tips & tricks, software, info, etc. title url cover text TIMEX SINCLAIR 1500 HOME COMPUTER - USER MANUAL http://www.ts1000.us/usermanuals.htm /media/museum/docs/couvs/ts1500_user-manual.jpg [**TIMEX SINCLAIR 1500 HOME COMPUTER - USER MANUAL**](http://www.ts1000.us/usermanuals.htm)written by Timex Computer Corporation / Charles F. Durang  compiled/archived by Bill Hicks\  type of document : PDF\  size : 36 MB\  source : [www.ts1000.us](http://www.ts1000.us/) /museum/timex-computers-tc-2048 /museum/timex-sinclair-2068 639 url date https://web.archive.org/web/20230604043655/http://www.old-computers.com/museum/computer.asp?c=639 2023-06-04

The Timex-Sinclair 1500 is basicaly a Sinclair ZX-81 in a ZX Spectrum case with 16 KB RAM.

Timex marketed the Sinclair computers on the North American market. The ZX-81 was sold as the TS-1000 (with 2 KB RAM instead of 1 KB of the original model) and the ZX Spectrum as the forth-coming TS-2000 (which remained a prototype). As the sales of the TS-1000 were dangerously falling, Timex produced a mix between the ZX-81 and the ZX Spectrum: the TS-1500. The goal was to correct the weaknesses of the TS-1000: too small memory and awfull keyboard.

It's in fact just a ZX-81 with the 16 KB RAM expansion built inside a Spectrum style case. But the original black case turned silver for the TS-1500. To prove that it is exactly the Spectrum case re-used here, there is still the speaker grid underneath the system, whereas the TS-1500 has no sound feature! However there are minor cosmetic changes: the "sinclair" encarved logo on top of the case is replaced by a fake grid... In fact, this plastic case was the TS-2000 one (which was never produced), reused here for the TS-1500.

The chicklet keyboard is also an improvement (really?) over the flat membrane keyboard of the ZX-81. The keys layout is exactly the same as the ZX Spectrum. You can even use keyboard membranes of the Spectrum 48KB to replace the existing one if it breaks. Apart from that it remains a TS-1000. The connectors are the same (RF TV ouput, tape recorder, expansion bus) and the Basic is still the Sinclair Basic. A 16k RAM expansion (the same as the one sold for the TS-1000) can be used to reach 32 KB RAM.

However, the TS 1500 had a number of changes that made it different than just a TS 1000 / ZX-81 with 16k:

1. The ROM was updated to check for 16 KB memory and correct faults in the TS 1000 version (which corrected faults in the ZX81 version).
2. You could only add a 16 KB RAM pack (1016). To use any larger 3rd party RAM pack from the TS1000/ZX81 family you need to modify the motherboard.
3. Circuitry was added to allow you to choose which channel to display, 2 or 3, when you turned on the system by holding down the "3" key on the keyboard.
4. The motherboard is a complete redesign with 16 KB onboard and the ULA (Undefined Logic Array) was surface mounted and not socketed.

Despite its funky look, the TS-1500 did not sell well either. In 1983, who wanted to buy a ZX-81 disguised whereas you could offer yourself a splendid Commodore 64 for a few more bucks!

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Contributed to this page : Bill Hicks