[[File:Sinclair ZX80.jpg|thumb|right|Sinclair ZX80]]
[[File:Sinclair-ZX81.png|thumb|right|Sinclair ZX81]]
[[File:Timex Sinclair 1500.png|thumb|right|Timex Sinclair 1500]]
The Sinclair ZX80 and ZX81, introduced in 1980 and 1981, are early budget microcomputers notable for their price, fleeting popularity and diminutive quantity of components.
A substantial disadvantage of the design of these machines is that because the refresh cycle is commandeered for other purposes, they're built around an assumption of static RAM. As a result, each shipped with only 1kb at launch and expansions beyond 16kb were rare.
PAL/SECAM compatibility was not an issue on these machines as they could only output black-and-white video signals anyway. Maybe that fooled Lord Sinclair into neglecting SECAM on its following machine, the [[ZX Spectrum]].
<br>
== Clones ==
Timex Sinclair was a joint venture established between Sinclair Research and Timex Corporation in an effort to gain an entry into the rapidly growing early-1980s home computer market in North America. They produced 2 modified versions of the ZX81:
*TS 1000, introduced in July 1982 and essentially a modified ZX81 with 2 KB RAM.
*TS 1500, introduced in August 1983, it was a TS 1000 with 16 KB RAM and a ZX Spectrum-like case and keyboard.
<br>
== Links ==
*[https://youtu.be/DElx9pk2oks ZX81 advertisements]
*[https://www.timexsinclair.com/ Timex Sinclair - The Authoritative Website]
*[http://searle.x10host.com/zx80/zx80.html Grant's Sinclair ZX80 Homebuilt hardware]
*[https://oldcomputer.info/8bit/zx81/ULA/ula.htm ZX81 ULA replacement] [[Media:Esquemas ZX81 ULA Andy Rea printable.pdf|ZX81 Project]] [[Media:ZX81 Complete printable.pdf|ZX81 Complete]]
*[https://archive.org/details/TimexSinclairEphemera/Zx81AssemblyManual/mode/2up ZX81 Assembly Instructions]
*[https://8bit-museum.de/heimcomputer-2/sinclair/sinclair-scans/scans-zx81-video-display-system/ ZX81 Video Display System]
*[https://problemkaputt.de/zxdocs.htm Noca$h's ZXdocs]
*[https://oldcomputer.info/8bit/zx81/ULA/ula.htm ZX81 ULA replacement] [[Media:Esquemas ZX81 ULA Andy Rea printable.pdf|ZX81 Project]]
*[https://youtu.be/1Jr7Q1yJOUM Documentary - The Sinclair ZX80, ZX81, and Timex Sinclair 1000] by [[The 8-Bit Guy]]
*[https://youtu.be/spxAQkTzvDQ Sinclair ZX81 (Timex 1000) Grandaddy of Computers] by [[Nostalgia Nerd]]
*[https://youtu.be/Liqd7ZoBVEI SINCLAIR ZX80 qDorGWU1k3A Sinclair ZX81 - Histoire & Jeuxrevolutionary or scam ?] [https://youtu.be/6eTGX_sEqPM ZXPAND+ ZX81's lethal weapon] [https://youtu.be/kTw8uo-53lc TOP 20 games for the Sinclair ZX81] by [[OlipixRetrotech]]*[https://youtu.be/qeKSV1GT6Nw Sinclair ZX81 Liqd7ZoBVEI ZX80 - Machine révolutionnaire ou grosse bouse ?Histoire & Jeux] [https://youtu.be/GjHgIpHPgq4 Le mystère de l'ordinateur en bois] by [[Olipix]] <br>
[[Category:Non CPC Computers]]