The time between (a) the instant that a signal at the input of a device or circuit exceeds the activation threshold of the device or circuit and (b) the instant that the device or circuit reacts in a specified manner, or to a specified degree, to the input.
Note: Attack time occurs in devices such as clippers, peak limiters, compressors,… (Read More →)

A switched circuit that provides an attendant with a manual means for call completion and control.
Note: An attendant access loop might be given a specific telephone number. Synonym access loop.

A network-provided service feature that allows an attendant to establish a conference connection of three or more users.

The part of a switching system used by an attendant, i.e., an operator, to assist users in call completion and use of special services.

In [a] trusted-computing-base (TCB) design, a character entered from a terminal that tells the TCB the user wants a secure communications path from the terminal to some trusted node to provide a secure service for the user. [INFOSEC-99]

The attention signal to be used by AM, FM, and TV broadcast stations to actuate muted receivers for inter-station receipt of emergency cuing announcements and broadcasts involving a range of emergency contingencies posing a threat to the safety of life or property. [47CFR]

The decrease in intensity of a signal, beam, or wave as a result of absorption of energy and of scattering out of the path to the detector, but not including the reduction due to geometric spreading. [After JP1]
Note 1: Attenuation is usually expressed in dB.
Note 2: "Attenuation" is often used as a misnomer for "attenuation coefficient," which is… (Read More →)

The rate of diminution of average power with respect to distance along a transmission path.
Note: The attenuation coefficient is often calculated as the sum of the absorption coefficient and the scattering coefficient. Synonym attenuation rate.

1. The real part of the propagation constant in any electromagnetic propagation medium.
Note 1: The attenuation constant is usually expressed as a numerical value per unit length.
Note 2: The attenuation constant may be calculated or experimentally determined for each medium.
2. For a particular propagation mode in an optical fiber, the real part of the axial propagation constant.

The difference in loss at specified frequencies relative to the loss at 1004 Hz, unless otherwise specified. [NECA/FCC-5]