The Lone C++ Coder's Blog

The Lone C++ Coder's Blog

The continued diary of an experienced C++ programmer. Thoughts on C++ and other languages I play with, Emacs, functional, non functional and sometimes non-functioning programming.

Timo Geusch

2-Minute Read

I don’t usually do Happy New Year posts, but given how “well” 2020 went I thought it was appropriate to start 2021 with a whimsy post.  This post is probably going to date me since it’s been a few years - OK, decades - since these were current.

Well, it’s not the actual computer, but the same model. I was first exposed to computers during the personal computer heyday of the early 1980s. Back then, my school had two computers, one TRS 80 Model 3 and one Sinclair ZX81. The ZX81 was used to teach pupils rudimentary programming. I wouldn’t be surprised if one of the teachers actually built it from a kit as that was the cheapest way to get into one.

Keep in mind that I grew up in Europe where computers like the Apple ][ were very expensive and didn’t gain much traction in the educational field. Or with hobbists, either. Yes, there were some around but you saw a lot more VIC20s, C64s or Ataris. A lot of schools including mine bought European manufactured computers like Sinclairs and later, Amstrad/Schneider CPC 464s.

Either way I probably watched too many retro computing videos on YouTube and ended up finding a Timex 1000 on eBay. For those not well versed in personal computer history, Timex sold variants of Sinclair computers in the US. Here it is, in all its glory:

My Timex 1000/Sinclair ZX81

My Timex 1000 (nee Sinclair ZX81) in all it’s glory

I actually bought this computer a couple of year ago. Between a house move, work and a bunch of other projects it mostly sat in its box. It is very clean and doesn’t appear to have seen a lot of use, so I’m hopeful that I’ll be able to get it working with minimal effort. If not, well, it’s a cheap way to polish my soldering skills.

As the ZX81 only came with 1KB of RAM - which included the video RAM - there isn’t that much that you can do with one out of the box. Fortunately this one came with the humongous 16KB RAM expansion that connects on the back.

ZX81 with 16KB RAM expansion

ZX81 with 16KB RAM expansion

Those expansions were notorious for causing involuntary resets if you looked at the computer funny. They actually connect straight the motherboard and are only held on by the connector itself, so any movement is, well, not great.

Also, I guess the warranty has run out:

Timex 1000 warranty slip

The warranty. Probably expired

Anyway, Happy 2021. Normal service with be resumed shortly.

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A developer's journey. Still trying to figure out this software thing after several decades.