US3833766A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voiced controlled gain switched loud-speaking telephone system
Assignee: GLOBAL SYST DESIGN CORP
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Filing: 1972-10-18
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Granted: 1974-09-03
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Expires: 1992-10-18
Abstract
Abstract A loud-speaking telephone system having voice controlled gain switched transmit and receive channel amplifiers, voice controlled gain switched amplifier gain control circuits, a two to four wire hydrid bridge with telephone line loop d.c. current bypass circuit and a telephone line impedance balancing network. The loud-speaking telephone system has provisions for permitting alternative conventional handset usage and it may be integrated with an automatic telephone dialing system.
Inventors
- 👤 A Eklof
- 👤 R Binks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:29
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
138 words
A voice controlled gain switched loud-speaking telephone system having a loud-speaker, a receiving channel with a receive detector and a receive amplifier gain switch and having a transmitting channel with a transmit detector and a transmit amplifier gain swtich wherein the improvement comprises: a receive detector gain switch operatively connected to said transmit detector and to said receive detector, and a transmit detector gain switch operatively connected to said receive detector and to said transmit detector, said transmit detector having means to increase the signal loss in said receive detector gain switch and means to increase the signal loss in said receive amplifier gain switch when the system is in the transmit condition, said receive detector having means for causing an increased signal loss in said transmit detector gain switch when the system is in the receive condition.
Claim 2
Dependent Claim
138 words
A voice controlled gain switched loud-speaking telephone system having a loud-speaker, a receiving channel with a receive detector and a receive amplifier gain switch and having a transmitting channel with a transmit detector and a transmit amplifier gain swtich wherein the improvement comprises: a receive detector gain switch operatively connected to said transmit detector and to said receive detector, and a transmit detector gain switch operatively connected to said receive detector and to said transmit detector, said transmit detector having means to increase the signal loss in said receive detector gain switch and means to increase the signal loss in said receive amplifier gain switch when the system is in the transmit condition, said receive detector having means for causing an increased signal loss in said transmit detector gain switch when the system is in the receive condition.
Claim 3
Dependent Claim
28 words
The telephone system of claim 1, further comprising means for decreasing the signal loss in said transmit amplifier gain switch when the system is in the transmit condition.
Claim 4
Dependent Claim
29 words
The telephone system of claim 1, further comprising means for producing a low signal loss in said transmit detector gain switch when the system is in the transmit condition.
Claim 5
Dependent Claim
42 words
The telephone system of claim 1, wherein said receive detector gain switch and said transmit detector gain switch each comprises voltage controlled gain switching elements and means for delaying the gain switching response of said gain switching elements to gain control voltages.
Claim 6
Dependent Claim
45 words
The telephone system of claim 4, wherein said means for delaying the gain switching response of said gain switching elements comprise means for imposing a shorter delay upon application of said gain control voltages than the delay occurring upon removal of said gain control voltages.
Claim 7
Dependent Claim
20 words
The telephone system of claim 4, wherein each of said voltage controlled gain switching elements includes a field effect transistor.
Claim 8
Dependent Claim
23 words
The telephone system of claim 1, further comprising means for connecting said voice controlled gain switched loud-speaking telephone system to automatic dialing circuits.
Claim 9
Dependent Claim
47 words
The telephone system of claim 7, wherein said connecting means comprises an outpulse relay adapted to be connected to said automatic dialing circuits, a receiver muting relay adapted to be connected to said automatic dialing circuits and a hands free relay connected to said receiver muting relay.
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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) | 1977-09-02 | 1978-03-04 | 1978-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-02 | 1982-03-04 | 1982-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-02 | 1986-03-04 | 1986-09-03 | $7700.00 | Window Closed / Lapsed |