US PATENT SUBCLASS 380 / 20
.~.~ Control coding


Current as of: June, 1999
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380 /   HD   CRYPTOGRAPHY

9  DF  ELECTRIC SIGNAL MODIFICATION (E.G., SCRAMBLING) {18}
10  DF  .~ Video {10}
20.~.~ Control coding


DEFINITION

Classification: 380/20

Control coding:

(under subclass 10) Subject matter which transmits an auxiliary signal between the transmitter and receiver for actuation or modification of an encrypting or decrypting function.

(1) Note. Such control signals may be transmitted in either direction between the transmitter and receiver.

(2) Note. The auxiliary signals referred to above should be distinguished from normal pilot tones or decoding sequence signals which synchronize or phase lock a decrypting device but do not turn on, monitor, or modify the operation of decrypting equipment.

SEE OR SEARCH CLASS

348, Television,

5.5, for video signal access control equipment.