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US3205441A Expired / Lapsed US ⏱️ 0.0 years remaining

Frequency shift signaling system

Assignee: Western Union Telegraph Co
•
Filing: 1962-10-01
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Granted: 1965-09-07
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Expires: 1982-10-01
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Abstract

No abstract record available.

Inventors

  • 👤 Harry C Likel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 06:58
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/10; H04L27/12

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 193 words
A SYSTEM FOR PRODUCING FREQUENCY SHIFT KEYING SIGNALS, COMPRISING A SOURCE OF SIGNALS OF A SINGLE FREQUENCY, A FIRST BINARY DIVIDER CHAIN CONNECTED TO SAID SOURCE TO PRODUCE A FIRST GROUP OF SIGNALS OF LOWER FREQUENCIES THAN SAID SINGLE FREQUENCY, A KEYING SIGNAL SOURCE, A GATE CONNECTED TO THE KEYING SIGNAL SOURCE AND KEYED THEREBY, SAID GATE HAVING INPUTS CONNECTED IN CIRCUIT TO THE FIRST CHAIN FOR PASSING THERETHROUGH TWO SELECTED SIGNALS DERIVED FROM SAID GROUP, A SECOND BINARY DIVIDER CHAIN CONNECTED TO AN OUTPUT OF THE GATE FOR DERIVING FURTHER SIGNALS OF FREQUENCIES LOWER THAN SAID TWO SELECTED SIGNALS, A FILTER CONNECTED TO SAID SECOND CHAIN FOR CONVERTING SAID FURTHER SIGNALS TO SINE WAVEFORM, A CARRIER SIGNAL SOURCE, A HETERODYNING MODULATOR CONNECTED IN CIRCUIT WITH SAID CARRIER SIGNAL SOURCE AND SAID FILTER FOR PRODUCING SIDEBANDS CONTAINING FREQUENCY SHIFT KEYING SIGNALS AT DESIRED LINE FREQUENCIS, WHEREIN SAID CARRIER SIGNAL SOURCE COMPRISES A THIRD BINARY DIVIDER CHAIN CONNECTED TO THE FIRST CHAIN FOR DERIVING A CERTAIN ONE OF SAID GROUP OF SIGNALS AND FOR PRODUCING A CERTAIN CARRIER SIGNAL THEREFROM, AND MEANS CONNECTING THE THIRD CHAIN TO THE MODULATOR FOR APPLYING SAID CARRIER SI
Claim 2
Independent Claim 193 words
A SYSTEM FOR PRODUCING FREQUENCY SHIFT KEYING SIGNALS, COMPRISING A SOURCE OF SIGNALS OF A SINGLE FREQUENCY, A FIRST BINARY DIVIDER CHAIN CONNECTED TO SAID SOURCE TO PRODUCE A FIRST GROUP OF SIGNALS OF LOWER FREQUENCIES THAN SAID SINGLE FREQUENCY, A KEYING SIGNAL SOURCE, A GATE CONNECTED TO THE KEYING SIGNAL SOURCE AND KEYED THEREBY, SAID GATE HAVING INPUTS CONNECTED IN CIRCUIT TO THE FIRST CHAIN FOR PASSING THERETHROUGH TWO SELECTED SIGNALS DERIVED FROM SAID GROUP, A SECOND BINARY DIVIDER CHAIN CONNECTED TO AN OUTPUT OF THE GATE FOR DERIVING FURTHER SIGNALS OF FREQUENCIES LOWER THAN SAID TWO SELECTED SIGNALS, A FILTER CONNECTED TO SAID SECOND CHAIN FOR CONVERTING SAID FURTHER SIGNALS TO SINE WAVEFORM, A CARRIER SIGNAL SOURCE, A HETERODYNING MODULATOR CONNECTED IN CIRCUIT WITH SAID CARRIER SIGNAL SOURCE AND SAID FILTER FOR PRODUCING SIDEBANDS CONTAINING FREQUENCY SHIFT KEYING SIGNALS AT DESIRED LINE FREQUENCIS, WHEREIN SAID CARRIER SIGNAL SOURCE COMPRISES A THIRD BINARY DIVIDER CHAIN CONNECTED TO THE FIRST CHAIN FOR DERIVING A CERTAIN ONE OF SAID GROUP OF SIGNALS AND FOR PRODUCING A CERTAIN CARRIER SIGNAL THEREFROM, AND MEANS CONNECTING THE THIRD CHAIN TO THE MODULATOR FOR APPLYING SAID CARRIER SI

References Cited (Backward Citations)

US3031527A Cited
US3121197A Cited
US3102238A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1968-09-06 1969-03-08 1969-09-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1972-09-06 1973-03-08 1973-09-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1976-09-06 1977-03-08 1977-09-07 $7700.00 Window Closed / Lapsed

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