@caitlin Oh, the crazy thing is: it is a real valve. Just driven so tepidly that it does not glow - so it never breaks. Cos if it breaks you realise that a new one costs more than the whole device ;-)
@dBu_fs Taint the drive that does the glow though, the glow's the heater which is emitting all the electrons for acceleration and adsorption or whatever by the magic science plates of quantum bafflement. #bias#valves#glowy