Picture tube

a very large vacuum tube used in television to produce pictures. the simplest is the black and white (B/W) tube. the B/W tube has one electron "gun" assembly that accepts the signal. this signal turns the gun off and on as determined by the scene being scanned. located on the tube are 2 pairs of deflection coils used to move the beam to the varios X,Y coordinates. the signal in combination with the coils produce the picture.

in color sets the operation is essentially the same except there are 3 electron guns corresponding to the colors red, blue, and green.

these tubes require very high voltages to operate, a typical 25" color tube requires approx. 25 kilovolts.