re: watch with PLB
Didn't have any idea they could squeeze a 121Mhz beacon into something that small!
re: solar still
I think with 250 people to get 1/2G of water per day (minimum for drinking), I have to come up with something larger scale than a solar still. That's why I'm thinking of "industrializing" using the boiler to more aggressively produce steam from salt-water that is then condensed. I realize there are issues with removing the brine from the boiler, but I think if a pinhole is pulling the brine out the bottom while fresh seawater goes in the top, it will work.