A device on or adjacent to an outer door for announcing one's presence. It can be mechanical, directly sounding a bell, or a button that electrically sounds a chime or buzzer inside the building.
A button that activates an electric doorbell.
To ring many doorbells of (target people or an area) in an effort to contact people and thereby spread information or solicit.
To ring many doorbells in an effort to contact people and thereby spread information or solicit.
A device that can transmit radio signals.
The technology that allows for the transmission of sound or other signals by modulation of electromagnetic waves.
A device that can capture (receive) the signal sent over radio waves and render the modulated signal as sound.
The continuous broadcasting of sound via the Internet in the style of traditional radio.
On-board entertainment system in a car, usually including a radio receiver as well as the capability to play audio from recorded media.
To order or assist (to a location), using telecommunications.
To use two-way radio to transmit (a message) (to another radio or other radio operator).