The evacuation tip is a port on any glass envelope or vessel inside of which specific gasses or a vacuum must be held. They are very often seen on
nixies or
vacuum tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied.
The type kn ...
s. It is used to evacuate gases from the tube, and in the case of nixies, add the proper mix of gases before being sealed. It provides a convenient port for the amateur
glasshacker to introduce gases to alter the performance of the tube. It is also known as the "tubulation" or "pip".
Vacuum tubes
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