Patent US3123779A successfully refreshed from Google Patents.
US3123779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Difference of two low-frequency signals
Assignee: —
•
Filing: —
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Granted: 1964-03-03
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Expires: 1981-03-03
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:55
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/34; G; G06; G06G; G06G7/00; G06G7/12; G06G7/14; H03F3/00; H03F3/50; H03F3/52
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
100 words
A SUM AND DIFFERENCE PRODUCER FOR TWO LOW-FREQUENCY SIGNALS A AND B, COMPRISING: A FIRST FOLLOWER AMPLIFIER, A SECOND FOLLOWER AMPLIFIER, THE SIGNALS A AND B BEING FED TO THE INPUTS OF SAID FIRST AND SECOND FOLLOWERS REPECTIVELY, A FIRST VOLTAGE DIVIDER HAVING A CENTER TAP AND BEING CONNECTED BETWEEN THE OUTPUT CIRCUITS OF SAID FIRST AND SECOND FOLLOWERS, THE SUM SIGNAL A+B BEING TAKEN FROM SAID CENTER TAP, A THIRD FOLLOWER AMPLIFIER, SECOND AND THIRD VOLTAGE DIVIDERS EACH HAVING A CENTER TAP AND BEING CONNECTED FROM THE OUTPUT CIRCUITS OF SAID THIRD TO SAID FIRST AND SECOND FOLLOWERS RESPECTIVELY,
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) | 1967-03-03 | 1967-09-02 | 1968-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-03-03 | 1971-09-02 | 1972-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-03-03 | 1975-09-02 | 1976-03-03 | $7700.00 | Window Closed / Lapsed |