US4710971A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Channel selecting device for CATV terminal unit
Assignee: Pioneer Corp
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Filing: 1985-08-20
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Granted: 1987-12-01
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Expires: 2005-08-20
Abstract
Abstract In a channel selecting device for a CATV terminal unit, a channel code table is stored in a ROM of the terminal unit, and only a code arrangement in the channel code table is written in a RAM, whereby the rewriting data is compressed, the time required for the data writing operation is reduced, and the area occupied by the RAM decreased.
Inventors
- 👤 Takashi Nozaki
- 👤 Takashi Hashimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:31
CPC Classifications
H; H03; H03J; H03J5/00; H03J5/02; H03J5/0245; H03J5/0254; H03J5/0263
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
140 words
A channel selecting device of a CATV terminal unit in which displayed channels can be changed with respect to received channels comprising: a converter having a CATV signal as its input; an FSK receiver having said CATV signal as an input; a descrambler receiving the output of said converter as an input; a microcomputer for controlling said converter and said descrambler and having the said output signal of said FSK signal receiver as its input; a ROM for storing a programmed channel code table, said ROM accessed by said microcomputer; a memory containing a compressed code of said channel code table the contents of which can be externally written with respect to said displaying channels, said memory programmed by said microcomputer and the compressed code of said channel code table includes indications of first and last ones of continuous channels.
Claim 2
Dependent Claim
140 words
A channel selecting device of a CATV terminal unit in which displayed channels can be changed with respect to received channels comprising: a converter having a CATV signal as its input; an FSK receiver having said CATV signal as an input; a descrambler receiving the output of said converter as an input; a microcomputer for controlling said converter and said descrambler and having the said output signal of said FSK signal receiver as its input; a ROM for storing a programmed channel code table, said ROM accessed by said microcomputer; a memory containing a compressed code of said channel code table the contents of which can be externally written with respect to said displaying channels, said memory programmed by said microcomputer and the compressed code of said channel code table includes indications of first and last ones of continuous channels.
Claim 3
Dependent Claim
62 words
A channel selecting method for a CATV terminal unit in which displayed channels can be changed with respect to received channels, the improvement wherein only data indicative of first and last ones of continuous channels and data indicative of channels other than continuous channels is transmitted from a CATV control center to a terminal unit and stored in a rewritable memory thereof.
Claim 4
Dependent Claim
62 words
A channel selecting method for a CATV terminal unit in which displayed channels can be changed with respect to received channels, the improvement wherein only data indicative of first and last ones of continuous channels and data indicative of channels other than continuous channels is transmitted from a CATV control center to a terminal unit and stored in a rewritable memory thereof.
Claim 5
Dependent Claim
49 words
The channel selecting method of claim 2, wherein data of at least one of each pair of said first and last ones of said continuous channels has a bit set to a value indicating the presence of a respective first or last one of a sequence of continuous channels.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-30 | 1991-06-01 | 1991-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-30 | 1995-06-01 | 1995-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-30 | 1999-06-01 | 1999-12-01 | $7700.00 | Window Closed / Lapsed |