Definition of aspect for Students. 1  1 : the appearance of something : look The old house took on a dark and lonely aspect at night. 2  2 : a certain way in which something appears or may be thought of We considered every aspect of the question. 3  3 : a position facing a certain direction The house has a southern aspect.
Knob and tube wiring is the original wiring method used from the late 1800s until approximately 1945. It is a system that involved stringing individual conductor insulated wire across porcelain insulators called âknobs,â and through other porcelain insulators called âtubes.â.
Modern vacuum tubes, mostly miniature style. In electronics, a vacuum tube, an electron tube, or just a tube (North America), or valve (Britain and some other regions), is a device that controls electric current between electrodes in an evacuated container. Vacuum tubes mostly rely on thermionic emission of electrons from a hot filament or a cathode heated by the filament.