I don't really remember a lot from that young, but I know that when I was eight or so, in 1984, my father brought home a tiny "pocket computer" from a yard sale and we had fun programming it, and that seemed entirely normal to me. He was an engineering professor, and so I spent a fair bit of time when I was small visiting him in his office and playing with his box of turbine blades and with the toy tractor that one of the admins had. And then in 1985, when I was nine, he brought home an IBM PC and I started learning to write BASIC programs -- and, a bit later, helped him write programs that would do simple engineering computations and in a couple of cases would create numerical-milling-machine programs to make parts for his experiments.
Also my brother and I had vast amounts of LEGO bricks, and we already had a significant number of them when I was seven or so. That probably also contributed to the habits of making things. Once we got to an age of doing things with the Technic bricks, which would have started around 10 or 11, I was doing things like figuring out how to build a front-wheel-drive mechanism. (With the parts available at the time, it wasn't particularly satisfying and was a bit fragile, but it worked.)
I figure a lot of the influence was from my dad, partly just visibly doing engineer things at home and sharing what he was doing. I remember him, when I was young, sitting at the kitchen table tracing the connections on an 80-channel slip ring with a multimeter and labeling all the wires. When the engineering department had a rubber-band-powered dragster contest, we built an entry together (using, among other things, wheels from my Capsela set -- I remember that we had trouble with the wheels slipping and spinning when it started, so the night before the race he coated them in a bit of maple syrup so they would be sticky). And then, when I was ten, we built a new house -- which he and my mom designed, and I helped by helping building small cardboard models of the interior spaces and the outside and coloring them with my colored pencils. A bit later, when I was fourteen or so, the three of us (him and my brother and me) entered a contest to make a small water turbine that would lift a weight using water from an overhead tank -- he did most of the design, but showed us how to do the calculations for it and we helped in designing it.
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