Discussion (2 Comments)Read Original on HackerNews

Luc•32 minutes ago

TIL the shiny metal coating on top of vacuum tubes is not an X-ray shield, but a reactive coating to scavenge any remaining molecules out of the vacuum.

Cyan488•16 minutes ago

You'll find a similar thing in vacuum fluorescent displays as well [0].

[0]: https://ibb.co/XZHWLD3x

A Vacuum Diode for Make: Magazine

Discussion (2 Comments)Read Original on HackerNews