US3922508A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coded telephone line testing equipment
Assignee: Magnetic Controls Co
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Filing: 1974-01-14
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Granted: 1975-11-25
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Expires: 1994-01-14
Abstract
Abstract Telephone line testing equipment in which a series of alternating current tone pulses are transmitted from the central office along the line to a sensing means placed at a remote point in the circuit. The series of pulses are transmitted in a coded sequence. The sensing means receives the pulse sequence, decodes it, and connects the telephone line to suitable loopback testing circuits if the proper code is received.
Inventors
- 👤 Brian B Brady
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:35
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/46; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30; H04M3/301
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
151 words
Apparatus for the testing of a communication circuit from one point to another remote point comprising in combination: means for applying a coded series of pulses to the circuit, said pulses comprising a plurality of clock controlled evenly spaced pulses with shift register controlled code pulses between some of the evenly spaced pulses; sensing means in the circuit at the remote point for sensing said coded series of pulses; decoding means connected to said sensing means for receiving said series of pulses and decoding code has been received; and switching means connected to said decoding means operable to connect a loopback circuit to said communication circuit in response to the reception of the proper code said communication circuit including two pairs of wires and said switching means comprising a switch operable to connect said loopback circuit from one pair to the other pair and disconnect the remaining portion of the circuit.
Claim 2
Dependent Claim
151 words
Apparatus for the testing of a communication circuit from one point to another remote point comprising in combination: means for applying a coded series of pulses to the circuit, said pulses comprising a plurality of clock controlled evenly spaced pulses with shift register controlled code pulses between some of the evenly spaced pulses; sensing means in the circuit at the remote point for sensing said coded series of pulses; decoding means connected to said sensing means for receiving said series of pulses and decoding code has been received; and switching means connected to said decoding means operable to connect a loopback circuit to said communication circuit in response to the reception of the proper code said communication circuit including two pairs of wires and said switching means comprising a switch operable to connect said loopback circuit from one pair to the other pair and disconnect the remaining portion of the circuit.
Claim 3
Dependent Claim
44 words
The apparatus of claim 1 in which said means for applying comprises a clock means adapted to transmit said evenly spaced pulses and a shift register adapted to transmit said code pulses between some of the evenly spaced pulses in a predetermined sequential code.
Claim 4
Dependent Claim
43 words
The apparatus of claim 2 in which said decoding means comprises a shift register and decode matrix connected to process the code pulses received between the clock pulses and activate said switching means if the pulses are received in the proper coded sequence.
Claim 5
Dependent Claim
16 words
The apparatus Of claim 1 in which said pulses each comprise an alternating current tone signal.
Claim 6
Dependent Claim
16 words
The apparatus of claim 3 in which said pulses each comprise an alternating current tone signal.
Claim 7
Dependent Claim
87 words
The apparatus of claim 5 in which said sensing means comprises a pickup on one of said pairs of wires connected to a filtering means and a tone decoding means to produce single pulses in response to each of the alternating current pulses, and also a pair of AND gates connected to said tone decoding means and to a timer means which timer is connected to said tone decoding means so as to pass clock pulses through one AND gate and data pulses through the other gate.
Claim 8
Dependent Claim
87 words
The apparatus of claim 1 in which said sensing means comprises a pickup on one of said pairs of wires connected to a filtering means and a tone decoding means to produce single pulses in response to each of the alternating current pulses, and also a pair of AND gates connected to said tone decoding means and to a timer means which timer is connected to said tone decoding means so as to pass clock pulses through one AND gate and data pulses through the other gate.
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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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |