encrypted signal
61Copy protection — Copy protection, also known as content protection, copy obstruction, copy prevention and copy restriction, refer to techniques used for preventing the reproduction of software, films, music, and other media, usually for copyright reasons.[1]… …
62Mobile ticketing — Part of a series on Electronic commerce Online goods and services Streaming media Electronic books Softwar …
63Digital cinema — refers to the use of digital technology to distribute and project motion pictures. A movie can be distributed via hard drives, optical disks (such as DVDs and Blu ray Discs) or satellite and projected using a digital projector instead of a… …
64National Security Agency — NSA redirects here. For other uses, see NSA (disambiguation). For the Bahraini intelligence agency, see National Security Agency (Bahrain). National Security Agency Agency overview …
65Ultra — (sometimes capitalised ULTRA) was the name used by the British for intelligence resulting from decryption of encrypted German radio communications in World War II. The term eventually became the standard designation in both Britain and the United …
66HD Radio — HD Radio, which originally stood for Hybrid Digital , is the trademark for iBiquity s in band on channel (IBOC) digital radio technology used by AM and FM radio stations to transmit audio and data via a digital signal in conjunction with their… …
67Satellite television — List of digital television broadcast standards DVB standards (Europe) DVB S (satellite) DVB S2 DVB T (terrestrial) DVB T2 DVB C …
68Morse code — Chart of the Morse code letters and numerals Morse code is a method of transmitting textual information as a series of on off tones, lights, or clicks that can …
69Squelch — In telecommunications, squelch is a circuit function that acts to suppress the audio (or video) output of a receiver in the absence of a sufficiently strong desired input signal. Contents 1 Carrier squelch 2 Tone squelch and selective calling 2.1 …
70Radio — is the transmission of signals, by modulation of electromagnetic waves with frequencies below those of visible light.Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of… …
