5 ms·

Seemingly they can be recharged, one hour between two plates at 1000 V appears to be the soft spot: https://aip.scitation.org/doi/10.1063/5.0023940 https://aip

by jaclaz 4y ago

Seemingly they can be recharged, one hour between two plates at 1000 V appears to be the soft spot: https://aip.scitation.org/doi/10.1063/5.0023940 https://aip.scitation.org/doi/10.1063/5.0023940 just imagine the cost of either re-processing the existing masks or having 1000 V "re-chargers" at home ...

throwanem 4y ago
A bit like the old quartz-fiber radiation dosimeters, I suppose - those actually were a consumer product [1], along with the high-voltage DC charger required to "zero" them for reuse, back some 60 or so years ago and a fair bit before safety was invented. [1] https://www.orau.org/health-physics-museum/collection/civil-defense/citizens/bendix-family-radiation-kit.html https://www.orau.org/health-physics-museum/collection/civil-...
- dylan604 4y ago
  >a fair bit before safety was invented. i still remember the oscillating fan at my grandparents' house from the 50s. It was a 12" fan made out of solid metal. Not one piece of plastic to be found any where on this thing. The blades looked like something from the back of a Naval ship. The interesting thing to me was the grate covering the fan. To this day, I'm really not sure of the purpose. I could easily stick my hand through the grate today as an adult. Yes, this fan still works today as well as it did when I was a kid and the fan was already 30 years old. Something like this: https://i.etsystatic.com/15784874/r/il/432676/2183412824/il_794xN.2183412824_ebtf.jpg https://i.etsystatic.com/15784874/r/il/432676/2183412824/il_... Clearly, safety was not invented at that time.
  - throwanem 4y ago
    Oh, I know the type very well! As a kid I often put ours on a chair by my bed. Even then I didn't really feel great about that, but when you don't have AC, it doesn't take much trying to sleep through a Mississippi summer night before you decide it's worth the risk for enough breeze not to feel like you're drowning. Ours was especially delightful too in having the speed control on the front of the base, so you couldn't even turn it off without having to think about what life might be like with everyone calling you "Stumpy". As far as I could ever tell, the grate's only there to keep it from sucking up curtains, and to keep you from getting caught up between the fan blades and the pedestal; with the torque out of those old motors, it'd certainly take off a finger and probably break an arm. For everything else you're on your own, which is why I don't really mind the scar I still have on my right middle knuckle from the only time I ever tried to turn it up to "high" without turning a light on first - if I'd missed the lever by a quarter inch more, that old cast-iron widowmaker would've given me a whole lot worse.
  - toast0 4y ago
    > The interesting thing to me was the grate covering the fan. To this day, I'm really not sure of the purpose. I could easily stick my hand through the grate today as an adult. The cage probably maybe protects the blades from hitting the ground if tipped over? No need to protect them from fleshy objects though, those will move one way or another.

by jaclaz 4y ago

throwanem 4y ago

A bit like the old quartz-fiber radiation dosimeters, I suppose - those actually were a consumer product [1], along with the high-voltage DC charger required to "zero" them for reuse, back some 60 or so years ago and a fair bit before safety was invented. [1] https://www.orau.org/health-physics-museum/collection/civil-defense/citizens/bendix-family-radiation-kit.html https://www.orau.org/health-physics-museum/collection/civil-...

dylan604 4y ago
>a fair bit before safety was invented. i still remember the oscillating fan at my grandparents' house from the 50s. It was a 12" fan made out of solid metal. Not one piece of plastic to be found any where on this thing. The blades looked like something from the back of a Naval ship. The interesting thing to me was the grate covering the fan. To this day, I'm really not sure of the purpose. I could easily stick my hand through the grate today as an adult. Yes, this fan still works today as well as it did when I was a kid and the fan was already 30 years old. Something like this: https://i.etsystatic.com/15784874/r/il/432676/2183412824/il_794xN.2183412824_ebtf.jpg https://i.etsystatic.com/15784874/r/il/432676/2183412824/il_... Clearly, safety was not invented at that time.
- throwanem 4y ago
  Oh, I know the type very well! As a kid I often put ours on a chair by my bed. Even then I didn't really feel great about that, but when you don't have AC, it doesn't take much trying to sleep through a Mississippi summer night before you decide it's worth the risk for enough breeze not to feel like you're drowning. Ours was especially delightful too in having the speed control on the front of the base, so you couldn't even turn it off without having to think about what life might be like with everyone calling you "Stumpy". As far as I could ever tell, the grate's only there to keep it from sucking up curtains, and to keep you from getting caught up between the fan blades and the pedestal; with the torque out of those old motors, it'd certainly take off a finger and probably break an arm. For everything else you're on your own, which is why I don't really mind the scar I still have on my right middle knuckle from the only time I ever tried to turn it up to "high" without turning a light on first - if I'd missed the lever by a quarter inch more, that old cast-iron widowmaker would've given me a whole lot worse.
- toast0 4y ago
  > The interesting thing to me was the grate covering the fan. To this day, I'm really not sure of the purpose. I could easily stick my hand through the grate today as an adult. The cage probably maybe protects the blades from hitting the ground if tipped over? No need to protect them from fleshy objects though, those will move one way or another.