US4599646A
Expired / Lapsed
US
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Method and apparatus for identifying unauthorized or defective converter/decoder boxes in CATV system
Assignee: D-TEC INDUSTRIES Inc
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Filing: 1984-05-18
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Granted: 1986-07-08
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Expires: 2004-05-18
Abstract
Abstract A head-end apparatus for a CATV system is provided for facilitating identification of unauthorized or defective converter/decoder boxes in the system. According to the invention, an IF audio signal, representing the aural portion of the program source to be transmitted, is applied to a scrambler which generates a scrambled IF audio signal having a scramble signal component. The scrambler has a synchronization rate set by a program source having a sync rate different than the sync rate of the program source to be transmitted. The scrambled IF audio signal is then combined with an IF video signal, representing the video portion of the program source to be transmitted, to produce a composite signal. The composite signal is then modulated to the desired CATV channel output frequency and transmitted to the user. In operation, an unauthorized or defective converter/decoder box in the CATV system injects the scramble signal component of the scrambled IF audio signal on the unscrambled video IF signal, thus scrambling a non-premium channel of a CATV system. When the user notifies the CATV system operator of the defective condition on the non-premium channel, an indication is provided that the converter/decoder box is either unauthorized or defective.
Inventors
- 👤 Johnny L. Cottam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:43
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/167
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
180 words
A head-end apparatus for a CATV system for identifying unauthorized or defective converter/decoder boxes, comprising: channel means for receiving a first program source and generating IF audio and video signals, said first program source having a synchronization rate; scrambler means having an input connected to said channel means for receiving said IF audio signal and generating a scrambled IF audio signal having a scramble signal component, said scrambler means having a synchronization rate set by a second program source input thereto, said second program source having a synchronization rate different from said synchronization rate of said first program source; and combiner means connected to said channel means and said scrambler means for receiving said IF video signal and said scrambled audio signal, respectively, and generating a composite signal; said channel means connected to said combiner means for receiving said composite signal and generating a CATV channel output signal, whereby an unauthorized or defective converter/decoder box applies said scramble signal component of said scrambled IF audio signal to said IF video signal to scramble a non-premium channel of the CATV system.
Claim 2
Dependent Claim
180 words
A head-end apparatus for a CATV system for identifying unauthorized or defective converter/decoder boxes, comprising: channel means for receiving a first program source and generating IF audio and video signals, said first program source having a synchronization rate; scrambler means having an input connected to said channel means for receiving said IF audio signal and generating a scrambled IF audio signal having a scramble signal component, said scrambler means having a synchronization rate set by a second program source input thereto, said second program source having a synchronization rate different from said synchronization rate of said first program source; and combiner means connected to said channel means and said scrambler means for receiving said IF video signal and said scrambled audio signal, respectively, and generating a composite signal; said channel means connected to said combiner means for receiving said composite signal and generating a CATV channel output signal, whereby an unauthorized or defective converter/decoder box applies said scramble signal component of said scrambled IF audio signal to said IF video signal to scramble a non-premium channel of the CATV system.
Claim 3
Dependent Claim
58 words
The head-end apparatus for a CATV system as described in claim 1 wherein said channel means includes first and second modulators, said first modulator for receiving said first program source and generating said IF audio and video signals, said second modulator connected to said combiner means for receiving said composite signal and generating said CATV channel output signal.
Claim 4
Dependent Claim
34 words
The head-end apparatus for a CATV system as described in claim 2 wherein said input of said scrambler means include a first terminal connected to said first modulator for receiving said IF audio signal.
Claim 5
Dependent Claim
39 words
The head-end apparatus for a CATV system as described in claim 3 wherein said input includes a second terminal for normally receiving an IF video signal, said scrambler means including a resistor connected between said second terminal and ground.
Claim 6
Dependent Claim
30 words
The head-end apparatus for a CATV system as described in claim 1 wherein said scrambler means includes a video output, and a resistor connected between said video output and ground.
Claim 7
Dependent Claim
41 words
The head-end apparatus for a CATV system as described in claim 1 wherein said scrambler means includes an IF output having first and second terminals, said first terminal connected to said combiner means for applying said scrambled IF audio signal thereto.
Claim 8
Dependent Claim
27 words
The head-end apparatus for a CATV system as described in claim 6 wherein said scrambler means further includes a resistor connected between said second terminal and ground.
Claim 9
Dependent Claim
220 words
A head-end apparatus for a CATV system for identifying unauthorized or defective converter/decoder boxes, comprising: a channel modulator, including a signal processing circuit and a first modulator, for receiving a first program source and generating IF audio and video signals, said first program source having a synchronization rate, said channel modulator also including a second modular; a scrambler having an IF input connected to an output of said first modulator for receiving said IF audio signal and generating, at an IF output thereof, a scrambled IF audio signal having a scramble signal component, said scrambler having a horizontal synchronization rate set by a second program source input thereto, said second program source having a synchronization rate different from said synchronization rate of said first program source; and a combiner connected to said IF output of said scrambler and the output of said first modulator for receiving said scrambled IF audio signal and said IF video signal, respectively, and generating in response thereto a composite signal; said second modulator connected to said combiner for receiving said composite signal and generating a CATV channel output signal, whereby an unauthorized or defective converter/decoder box in said CATV system applies said scramble signal component of said scrambled IF audio signal to said IF video signal to scramble a non-premium channel of the CATV system.
Claim 10
Dependent Claim
220 words
A head-end apparatus for a CATV system for identifying unauthorized or defective converter/decoder boxes, comprising: a channel modulator, including a signal processing circuit and a first modulator, for receiving a first program source and generating IF audio and video signals, said first program source having a synchronization rate, said channel modulator also including a second modular; a scrambler having an IF input connected to an output of said first modulator for receiving said IF audio signal and generating, at an IF output thereof, a scrambled IF audio signal having a scramble signal component, said scrambler having a horizontal synchronization rate set by a second program source input thereto, said second program source having a synchronization rate different from said synchronization rate of said first program source; and a combiner connected to said IF output of said scrambler and the output of said first modulator for receiving said scrambled IF audio signal and said IF video signal, respectively, and generating in response thereto a composite signal; said second modulator connected to said combiner for receiving said composite signal and generating a CATV channel output signal, whereby an unauthorized or defective converter/decoder box in said CATV system applies said scramble signal component of said scrambled IF audio signal to said IF video signal to scramble a non-premium channel of the CATV system.
Claim 11
Dependent Claim
30 words
The head-end apparatus for a CATV system as described in claim 8 wherein said IF input of said scrambler includes a video input terminal connected to ground through a resistor.
Claim 12
Dependent Claim
31 words
The head-end apparatus for a CATV system as described in claim 8 wherein said IF output of said scrambler includes an IF video output terminal connected to ground through a resistor.
Claim 13
Independent Claim
163 words
A method for idnetifying unauthorized or defective converter/decoder boxes in a CATV system having a scrambler for encoding a premium channel, comprising the steps of: receiving a first program source representing said premium channel and generating IF audio and video signals in response thereto; applying a second program source to said scrambler to set the synchronization rate thereof, said second program source having a synchronization rate different from the synchronization rate of said first program source; applying said IF audio signal to the scrambler to generate a scrambled IF audio signal having a scramble signal component; combining said IF video signal and said scrambled IF audio signal to generate a composite signal; and generating a CATV channel output signal from said composite signal, whereby an unauthorized or defective converter/decoder box in said CATV system removes said scramble signal component from said scrambled IF audio signal, and applies said component to said video IF signal to scramble a non-premium channel of the CATV system.
Claim 14
Independent Claim
163 words
A method for idnetifying unauthorized or defective converter/decoder boxes in a CATV system having a scrambler for encoding a premium channel, comprising the steps of: receiving a first program source representing said premium channel and generating IF audio and video signals in response thereto; applying a second program source to said scrambler to set the synchronization rate thereof, said second program source having a synchronization rate different from the synchronization rate of said first program source; applying said IF audio signal to the scrambler to generate a scrambled IF audio signal having a scramble signal component; combining said IF video signal and said scrambled IF audio signal to generate a composite signal; and generating a CATV channel output signal from said composite signal, whereby an unauthorized or defective converter/decoder box in said CATV system removes said scramble signal component from said scrambled IF audio signal, and applies said component to said video IF signal to scramble a non-premium channel of the CATV system.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-07 | 1990-01-06 | 1990-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-07 | 1994-01-06 | 1994-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-07 | 1998-01-06 | 1998-07-08 | $7700.00 | Window Closed / Lapsed |