An undesired signal occurring in the main channel from modulation of the stereophonic channel or that occurring in the stereophonic channel from modulation of the main channel. [47CFR]

A subcarrier within the FM broadcast baseband used for transmitting signals for stereophonic sound reception of the main broadcast program service. [47CFR]

Abbreviation for standard time and frequency signal. See standard time and frequency signal service.

Nonmoving visual information, i.e., fixed images, such as graphs, drawings, and pictures.

Video imagery that is not intended to convey the appearance of movement.

In a quantum mechanical system, the radiation emitted when the internal energy of the system drops from an excited level (induced by the presence of radiant energy at the same frequency) to a lower level.
Note: An example of stimulated emission is the radiation from an injection laser diode operated above the lasing threshold.

Abbreviation for standard telegraph level, studio-to-transmitter link, Satellite Time and Location.

See stop signal.

1. In start-stop transmission, a signal at the end of a character that prepares the receiving device for the reception of a subsequent character. A stop signal is usually limited to one signal element having any duration equal to or greater than a specified minimum value.
2. A signal to a receiving mechanism to wait for the next signal.

In facsimile systems, a signal used for stopping the process of converting the electrical signal to an image on the record medium.