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US3810247A Expired / Lapsed US ⏱️ 0.0 years remaining

Telephone set circuit

Assignee: Iwatsu Electric Co Ltd
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Filing: 1971-09-27
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Granted: 1974-05-07
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Expires: 1991-09-27
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Abstract

Abstract A telephone set circuit having a talking circuit formed by a transmitter, a receiver, an induction coil and a balancing network. The induction coil serves to couple the receiver and the transmitter in conjugate relationship between a two-line subscriber''s line and the balancing network. The balancing network includes a series-connected combination of a nonlinear resistance element and an ohmic resistance. A control circuit formed into a four terminal network is connected in cascade with terminals of the talking circuit. The control circuit is formed by use of an inductance element or an inductance circuit for compensating the capacitive component of the subscriber''s line, to which the telephone set circuit is connected, and a nonlinear resistance element for controlling the value of the inductance element or the inductance circuit in accordance with the supplied direct current of the subscriber''s line.

Inventors

  • 👤 Y Ono

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 04:35
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/738; H04M1/76

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 131 words
A telephone set circuit, comprising: a two line subscriber''s line having an impedance characteristic having a capacitive component; a talking circuit comprising a transmitter, a receiver, a balancing network comprising a series-connected combination of a nonlinear resistance element and an ohmic resistance element, and an induction coil coupling said transmitter and said receiver in conjugate relationship between said two-line subscriber''s line and said balancing network; and a control circuit comprising a four Terminal network connected in parallel with said talking circuit and said two-line subscriber''s line, said control circuit comprising first means including inductance means for compensating the capacitive component of said subscriber''s line, and second means including a nonlinear resistance element for controlling the value of the inductance means in accordance with the supplied direct current through said subscriber''s line.
Claim 2
Dependent Claim 131 words
A telephone set circuit, comprising: a two line subscriber''s line having an impedance characteristic having a capacitive component; a talking circuit comprising a transmitter, a receiver, a balancing network comprising a series-connected combination of a nonlinear resistance element and an ohmic resistance element, and an induction coil coupling said transmitter and said receiver in conjugate relationship between said two-line subscriber''s line and said balancing network; and a control circuit comprising a four Terminal network connected in parallel with said talking circuit and said two-line subscriber''s line, said control circuit comprising first means including inductance means for compensating the capacitive component of said subscriber''s line, and second means including a nonlinear resistance element for controlling the value of the inductance means in accordance with the supplied direct current through said subscriber''s line.
Claim 3
Dependent Claim 39 words
A telephone set circuit according to claim 1, wherein said inductance means comprises an inductance element connected across said two-line subscriber''s line and wherein said nonlinear resistance element comprises a zener diode connected in parallel with said inductance element.
Claim 4
Dependent Claim 40 words
A telephone set circuit according to claim 2, wherein said control circuit further comprises an ohmic resistance element connected in series between the parallel circuit of said inductance element and said zener diode and one line of the subscriber''s line.
Claim 5
Dependent Claim 37 words
A telephone set circuit according to claim 2, wherein said control circuit further comprises two ohmic resistance elements respectively inserted in series between said inductance element and said zener diode and one line of the subscriber''s line.
Claim 6
Dependent Claim 119 words
A telephone set circuit according to claim 1, wherein said first means includes a transistor, a first ohmic resistance element connected across the base and the collector of said transistor and to one line of the subscriber''s line, a second ohmic resistance element one terminal of which is connected to the emitter of said transistor and the other terminal to the other line of the subscriber''s line, and a capacitor connected across the base of said transistor and said other terminal of the second ohmic resistance element, and wherein said second means comprises a first zener diode connected in parallel with said first resistance element, and a second zener diode connected in parallel with said second ohmic resistance element.
Claim 7
Dependent Claim 93 words
A telephone set circuit according to claim 1, wherein said second means comprises an ohmic resistance element and a first nonlinear negative resistance element connected in parallel and both elements connected between one of a pair of terminals of said four terminal network and one of the other pair of terminals of said four terminal network, and wherein said first means comprises an inductance element and a second nonlinear negative resistance element connected in series and both elements connected across one pair of the two pairs of terminals of said four terminal network.
Claim 8
Dependent Claim 24 words
A telephone set circuit according to claim 6, wherein at least one of said first and second nonlinear negative resistance elements comprises a thermistor.
Claim 9
Dependent Claim 25 words
A telephone set circuit according to claim 6, wherein at least one of said first and second nonlinear negative resistance element comprises a tunnel diode.
Claim 10
Dependent Claim 149 words
In a telephone system comprising a telephone circuit for transmitting and receiving information utilizing a two-line transmission line having an impedance characteristic wherein the magnitude of the impedance and the magnitude of the capacitive component of said impedance are dependent upon the physical properties of said transmission line; a control circuit connected in parallel between said telephone circuit and said transmission line for controlling the transmission and receiving attenuation characteristics of said telephone circuit, said control circuit comprising first means including inductance means for compensating for said capacitive component to impart a substantially resistive impedance to said transmission line, and second means including nonlinear resistance means for controlling the magnitude of said substantially resistive impedance of said transmission line; whereby said control circuit imparts to said telephone circuit a minimized variance in said transmission and receiving attenuation characteristics for an operable range of physical properties of said transmission line.
Claim 11
Dependent Claim 149 words
In a telephone system comprising a telephone circuit for transmitting and receiving information utilizing a two-line transmission line having an impedance characteristic wherein the magnitude of the impedance and the magnitude of the capacitive component of said impedance are dependent upon the physical properties of said transmission line; a control circuit connected in parallel between said telephone circuit and said transmission line for controlling the transmission and receiving attenuation characteristics of said telephone circuit, said control circuit comprising first means including inductance means for compensating for said capacitive component to impart a substantially resistive impedance to said transmission line, and second means including nonlinear resistance means for controlling the magnitude of said substantially resistive impedance of said transmission line; whereby said control circuit imparts to said telephone circuit a minimized variance in said transmission and receiving attenuation characteristics for an operable range of physical properties of said transmission line.
Claim 12
Dependent Claim 37 words
In a telephone systEm according to claim 9, wherein said inductance means includes an inductor connected across said two-line transmission line and wherein said nonlinear resistance means includes a zener diode connected in parallel with said inductor.
Claim 13
Dependent Claim 38 words
In a telephone system according to claim 10, wherein said control circuit further comprises a resistor connected in series between the parallel combination of said inductor and said zener diode and one line of said two-line transmission line.
Claim 14
Dependent Claim 47 words
In a telephone system according to claim 10, wherein said control circuit further comprises a resistor connected in series between said zener diode and one line of said transmission line and a resistor connected in series between said inductior and said one line of said transmission line.
Claim 15
Dependent Claim 109 words
In a telephone system according to claim 9, wherein said first means includes a transistor having a collector connected to one line of said transmission line, a first resistor connected across the base and the collector of said transistor, a second resistor having one end connected to the emitter of said transistor and the other end connected to the other line of said transmission line, a capacitor connected across said base of said transistor and said other end of said second resistor, and wherein said second means comprises a first zener diode connected in parallel with said first resistor and a second zener diode connected across said second resistor.
Claim 16
Dependent Claim 69 words
In a telephone system according to claim 9, wherein said second means include a resistor, a first nonlinear negative resistance element connected in parallel with said resistor, the parallel combination connected in series with one line of said transmission line, and wherein said first means includes an inductor and a second nonlinear negative resistance element connected in series with said inductor, the series combination connected across said transmission line.
Claim 17
Dependent Claim 24 words
In a telephone system according to claim 14, wherein at least one of said first and said nonlinear negative resistance elements comprise a thermistor.
Claim 18
Dependent Claim 25 words
In a telephone system according to claim 14, wherein at least one of said first and second nonlinear negative resistance elements comprise a tunnel diode.

References Cited (Backward Citations)

GB655774A Cited
US3239681A Cited
US3548111A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-05-06 1977-11-05 1978-05-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-05-06 1981-11-05 1982-05-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-05-06 1985-11-05 1986-05-07 $7700.00 Window Closed / Lapsed

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