You searched for: “electromagnetic focusings
electromagnetic focusing (s) (noun), electromagnetic focusings (pl)
A method of adjusting the electron beam in a television picture tube by varying the direct current flowing through the coils attached to the tube, and so, altering or changing the surrounding magnetic field: The electromagnetic focusing field is produced by sending an adjustable value of direct currents through a focusing coil mounted on the neck of the tube.
This entry is located in the following units: electro-, electr-, electri- (page 39) focus-, foci- (page 1)