US3731234A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined voice frequency transmission and dc signaling circuit
Assignee: AT&T Inc
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Filing: 1971-12-27
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Granted: 1973-05-01
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Expires: 1991-12-27
Abstract
Abstract A coupler exhibiting substantially improved insertion loss performance comprises a split winding transformer, an inductor network, and a capacitor network. The coupler longitudinally balances voiceband signals derived from a grounded source for transmission along a balanced cable pair and simultaneously provides metallic circuit continuity between the source and the cable pair for superimposed direct current (DC) and low frequency signaling. The transformer inductively transfers voiceband signals via its windings and, further, by having associated winding sections along the tip and ring connected series opposed, allows for the transfer of DC and low frequency signals without impairment of voiceband transmission. The inductor network provides metallic circuit continuity between the transformer windings to effect this transfer of DC and low frequency signals and, in addition, suppresses the longitudinal voiceband signal components.
Inventors
- 👤 R Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:41
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/30; H03; H03H; H03H7/00; H03H7/42
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
183 words
A coupler for longitudinally balancing voice-band signals applied to its two input terminals and for providing the balanced signals at its two output terminals, said coupler comprising: a transformer including first and second identical primary winding sections connected series aiding and wound on a first core and first and second identical secondary winding sections also connected series aiding and wound on said first core, the inner ends of said secondary winding sections being connected to a reference potential, said input and output terminals respectively comprising the outer ends of said primary and secondary winding sections; and an inductor network including first and second coils connected series opposed and wound on a second core, each coil connecting associated inner ends of said primary and secondary winding sections whereby the first primary winding section, the first coil, and the first secondary winding section are connected in series, and the second primary winding section, the second coil, and the second secondary winding section are also connected in series, the voiceband signals appearing at said two output terminals being substantially balanced with respect to said reference potential.
Claim 2
Dependent Claim
183 words
A coupler for longitudinally balancing voice-band signals applied to its two input terminals and for providing the balanced signals at its two output terminals, said coupler comprising: a transformer including first and second identical primary winding sections connected series aiding and wound on a first core and first and second identical secondary winding sections also connected series aiding and wound on said first core, the inner ends of said secondary winding sections being connected to a reference potential, said input and output terminals respectively comprising the outer ends of said primary and secondary winding sections; and an inductor network including first and second coils connected series opposed and wound on a second core, each coil connecting associated inner ends of said primary and secondary winding sections whereby the first primary winding section, the first coil, and the first secondary winding section are connected in series, and the second primary winding section, the second coil, and the second secondary winding section are also connected in series, the voiceband signals appearing at said two output terminals being substantially balanced with respect to said reference potential.
Claim 3
Dependent Claim
54 words
The coupler of claim 1 also comprising a capacitor network for connecting the inner ends of said secondary winding sections to said reference potential, said coupler now being capable of also transmitting DC and low frequency signals via the metallic path comprising said primary winding sections, said inductor network, and said secondary winding sections.
Claim 4
Dependent Claim
32 words
The coupler of claim 2 wherein said capacitor network includes first and second serially connected capacitors, each capacitor connecting an associated inner end of said secondary winding sections to said reference potential.
Claim 5
Dependent Claim
24 words
The coupler of claim 2 wherein said first winding sections are connected series opposed and said second winding sections are also connected series opposed.
Claim 6
Dependent Claim
22 words
The coupler of claim 4 wherein said first core is of the permalloy type, said coupler exhibiting substantially improved pulse distortion performance.
Claim 7
Dependent Claim
102 words
A coupler for longitudinally balancing applied voiceband signals, said coupler comprising: transformer means further comprising split primary and secondary windings, the outer ends of said primary winding being responsive to said applied voiceband signals and the inner ends of said secondary winding being connected to reference potential; and inductor means further comprising first and second coils wound on a common core, each coil connecting an associated inner end of said primary winding to an associated inner end of said secondary winding, the voiceband signals appearing at the outer ends of said secondary winding being substantially balanced with respect to said reference potential.
Claim 8
Dependent Claim
102 words
A coupler for longitudinally balancing applied voiceband signals, said coupler comprising: transformer means further comprising split primary and secondary windings, the outer ends of said primary winding being responsive to said applied voiceband signals and the inner ends of said secondary winding being connected to reference potential; and inductor means further comprising first and second coils wound on a common core, each coil connecting an associated inner end of said primary winding to an associated inner end of said secondary winding, the voiceband signals appearing at the outer ends of said secondary winding being substantially balanced with respect to said reference potential.
Claim 9
Dependent Claim
50 words
The coupler of claim 6 also comprising capacitor means for connecting the inner ends of said secondary winding to said reference potential, said coupler now being capable of also transmitting DC and low frequency signals via the metallic path comprising said primary winding, said inductor means, and said secondary winding.
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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) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |