I presumed it was 100% levelling up unlocked them, until I learned how to make a lightstrip with 0 experience in electronics. Maybe a bug?
Lightstrips and antennas can be made with no electronics skill in 0.4.
A lightstrip is basically just clamping a light-emitter and some wires to a stack of batteries. It was added in 0.4, and yeah, a number of recipes are available from the start of the game.
In the current dev version, there are also a few recipes (very few) that can be learned by disassembling the end result, or reading certain books. In both cases, the game tells you when it’s possible to learn a recipe.
A lot of very simple stuff can be made with no skill whatsoever. Anything more complex just gets unlocked as your skill levels get higher.
E.g Boiling water? Very simple, no skill required. Homebrew Purifier? Best grab that chemistry textbook, son guy.
Also think about it, Making an antenna is absurdly simple IRL.
Of course, Cata Antennas are generally even more simple: Get a few nice pieces of silver cultery, bend into shape.
Additionally, some recipes can only be found in skill books, such as the battery expansion mod for electronics.
There’s also another book that teaches a few recipes, “To Serve Man”. It’s… it’s a cookbook.
That right there is a great name for a cook book, I approve.
I think my little Sebastian will need that. Sounds like a good book for a butler to have.
Although again, I’ll point out that book-learned recipes are not in 0.4, though they will be in 0.5 (and have been in the dev version for a little while).