Timex Sinclair 1500 computer

Timex Sinclair 1500

Introduced:	July 1983
Price:	US $79.95
CPU:	Zilog Z80A, 3.25MHz
RAM:	16K, 64K max
Display:	22 X 32 text (B&W)
	hooks to TV
Ports:	expansion, cassette
Peripherals:	Cassette recorder
	T/S printer
OS:	ROM BASIC

Once upon a time,

In February 1980, UK company Sinclair releases the Sinclair ZX-80, the first computer to ever sell for less than $200.00 (US).
It is comprised of a tiny case with a membrane-type keyboard, the cheapest and most inconvenient type possible.
One year later, in March of 1981, Sinclair releases the new and improved (and cheaper) Sinclair ZX-81, now only $99.00 (US)!
It still sports the same keyboard, but now has a much better BASIC programming language.
US company Timex had been manufacturing the ZX-81 for Sinclair in the UK, so in July 1982, with Sinclair's permission, they started selling the ZX-81 in America.
Although still identical to the Sinclair ZX-81, it will now be known as the Timex Sinclair 1000. Still only $99.00.
Finally, in July 1983, the transformation is complete! The lowly Sinclair ZX-80 has now morphed into the semi-useable Timex Sinclair 1500, sporting a brand-new keyboard and much more internal RAM.
The keyboard is only slightly larger, but now has actual keys (the rubbery-kind) with tactile-feedback, instead of just a plastic touch-surface.
Actually, those are the only difference - a new keyboard and more RAM. Besides being much better looking, it is nearly identical in operation to the TS 1000.

The TS 1500 uses your standard television for its display, "broadcasting" on either channel 2 or 3. It defaults to TV channel 2, but if you press the "3" on the keyboard within a few seconds of turning the computer on, it will then use channel 3 instead. Very tricky indeed!

This improved keyboard on the TS 1500 has the same layout as the earlier versions, meaning that each key may do up to five different functions, depending on how many keys are pressed and in what order.

Although the TS 1500 comes with 16K internal RAM, an external 16K RAM pack can be added for a total 32K RAM. A few keyboard commands (POKEs) are required for the system to recognize the additional memory space.

Being a very inexpensive computer system, an equally inexpensive data storage method makes the most sense. This was accomplished by utilizing a standard cassette recorder for data storage and retrieval. While almost any consumer recorder would work, Timex sold the very shiny Timex Sinclair 2020 recorder for that professional touch.

The motherboard of the TS 1500 is rather sparse, with only 5 IC chips for logic, and 8 more for the 16K of RAM. Interestingly enough, discounting the additional RAM, the TS 1500 still has more chips than the earlier but identical TS 1000.

This particular TS 1500 computer system was sold as part of an educational package - complete with carrying case, TS 2020 cassette recorder, hook-up wires and non-Timex specific training materials - all for only $295. Distributed by the National Education Corporation, this Technical Literacy Series includes:

The Magic of Computers
An "Inside" View
The System and the Software
Program Design - The Game Plan
Putting Your Microcomputer to Work
A Lesson in BASIC Programming
Computer Logic - The Limits of Computer Intelligence
Control Breaks - Taking Intermediate Totals
Tables and Arrays - Lists of Similar Data
Merging - Functions
Advanced Printing and Graphics Techniques


Related Links
TS 1500 from Lewin computer museum Sinclair User Magazine archives CRASH ZX Spectrum magazine


History of Sinclair Computers
1980: February - Sinclair Research announces the ZX80 computer in the North American market. 1981: March - Sinclair unveils the ZX81 in the UK, based on the Z80A microprocessor. 1981: December - Sinclair Research reports that it has shipped 250,000 ZX81 personal computers. 1982: April - Sinclair Research introduces the Sinclair ZX Spectrum in the UK. 1982: July - Timex Computer begins selling the Timex Sinclair 1000 through over 1000 Timex retail outlets. 1982: August - Sinclair Research reports that it has shipped 500,000 ZX81 personal computers in over 30 countries. 1983: January - Timex introduces the Timex/Sinclair 2000, which is their re-packaged Sinclair Spectrum for the North American market. Source: Chronology of Events in the History of Microcomputers

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Related Links

History of Sinclair Computers