How about something more ... Realistic

https://www.thebrighterside.news/post/mits-high-tech-hydroge...

That's the opposite of a tree, which turns drinking water into nothing

"Water harvesting" has been around for a long time. I think I first saw a water harvesting device in the U.S. Army Survival manual in the 1980s. It's an active research area and devices continue to improve.

Passive? Hydrophobic+Dessicant? dew collector? In the desert?

Dew collector seems to make the most sense for 1980