RIP Sir Clive Sinclair, 1940-2021
Without Clive Sinclair’s vision, none of this would exist. I am deeply in debt to his intellect, vision and inventions. Home computing pioneer Sir Clive Sinclair dies aged 81
Designing a Video Interface with No Prior Experience
Daniel Roy’s interest in computers started in high school, where he encountered his first computer. It had a video camera attached to it and he had his photo taken. It was enough to get him hooked. Years later, he received a Sinclair ZX81 as a Christmas gift from his wife.
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VLSI Technology SCLD Engineering Samples
Timex had several companies to work with in 1983 when they designed the replacement for the Spectrum ULA in the Timex Sinclair 2068. We know that Timex eventually selected NCR to make the SCLD in the 2068 that replaced the ZX Spectrum’s ULA.
DIY RGB Monitor Connection for T/S 2068
I recently purchased a Timex/Sinclair 2068 that had an 8-pin DIN socket on the back. I figured it might be a connection for an RGB monitor and, as it turns out, I was right. This circuit looked nothing like the other RGB designs I’ve seen.
DIY Keyboards for the ZX81 and TS 1000
The Sinclair ZX81/TS1000 keyboard was widely acknowledged as one of the more challenging aspects of using the computer. As a result, many commercial keyboard replacements were available in the UK and US. A number of the replacements available in the US were imported from the UK, like the dk’Tronics keyboard.
Jim Payne and Pheonix Enterprises
Jim Payne was one of many small, cottage industry supporters of Timex/Sinclair computers. He wrote several programs for the 1000 and 2068 and started a mail order business to sell them after Timex exited the market in 1984.
How to Fix 2068 Video
This solution only provides 8 colors: the intensity signal necessary for BRIGHT colors is not available in the TS 2068. The PicoVideo solution uses a Raspberry Pi Pico to provide full color and ULAplus features seamlessly with a VGA output. Inexpensive VGA to HDMI converters allow you to use almost any monitor.
Improved 2068 Video Converter
It is done. I’ve “improved” the 2068 signal as much as I can via converting the RGB to composite. It’s pretty good but not perfect: there’s some ghosting and some halo, both effects of the imperfect conversion/cleaning of the composite signals.
Interview with Rex Naden
Rex Naden was vice-president of research and development at Timex during the time they produced the Timex/Sinclair 1500 and 2068 computers. He spent thirty-five years in the semiconductor industry, holds fourteen US patents and earned his BA, MS and PhD degrees in Electrical Engineering from Rice University.
2068 Users and Odd-ball Printers
If you read enough of the old Timex/Sinclair newsletters, you’ll notice that two printers were especially popular with 2068 owners: the Gorilla Banana/Seikosha GP-100 and the Olivetti PR-2300 “inkjet”. And you may wonder why those two printers were especially popular.
Minstrel 3 Review
Being retired and finished with my combat pit, I was drawn to get out my ZX81 which had been stored in a plastic tub for 25 years. I was faced with two problems: 1) I had no RF TV sets and 2) did not have a usable cassette recorder.