Build Your Own Sinclair ZX81 Ad, BYTE Magazine, Volume 7, Number 9, September 1982

Yep. Tried one at a family friend's house with a RAM expansion pack hanging off the back that kept disconnecting because it was such a wobbly connection, and heavier than the computer itself. Then there was the fact it was only black & white. Seemed a really unreliable PITA, so I was iffy about getting one.

Then Captain Kirk advertised the VIC-20, and I was sold.

Yup! I remember it so well. I even remember seeing this ad in a magazine and begging my dad to order it.. I was 10 years old, and built it with him.

I also remember going to a home computer sale event in my hometown. No shops were selling computer stuff in that town yet. Men with beards and long hair laughing that I was buying 1k Chess to play on my new computer.

The location for that sale was turned into public toilets.

This was sadly before my time. One of the people in the original post did have one though.