US4024356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission system with balanced bridge to prevent low frequency cross talk
Assignee: US Philips Corp
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Filing: 1975-10-02
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Granted: 1977-05-17
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Expires: 1995-10-02
Abstract
Abstract Transmission system for transmitting signals modulating a carrier between two main stations via parallel coaxial lines the inner conductors and the non-earthed outer conductors of which are connected to the earthed main stations via capacitors. The main stations contain low-frequency signal sources which in parallel with direct-current supply sources are connected to the supply current loop for the repeaters included in the coaxial lines. The low-frequency cross-talk due to the low-frequency signals is suppressed by means of compensating circuits.
Inventors
- 👤 Jasper Hendrik Duimelaar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:24
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/44
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
167 words
A main transmission station for use at the junction of a pair of ungrounded coaxial transmission cables having repeaters therein, and a pair of coaxial transmission cables having grounded outer shields said station comprising, a first capacitor means for coupling between the respective inner conductors of said grounded and ungrounded cables and a second capacitor means for coupling between the respective outer shields of said grounded and ungrounded cables, whereby low-frequency cross-talk can occur due to significant voltages developed across the capacitor means coupled to the outer shields of said ungrounded cables, a pair of direct current source means for supplying the repeaters in said ungrounded cables, a pair of high frequency stop filter means for coupling said source means to said ungrounded cables respectively, each of said filters having a parallel capacitor, a pair of low frequency signal sources, and a pair of means for coupling said low frequency sources to said ungrounded cables respectively, said coupling means each including bridge means for suppressing said cross-talk.
Claim 2
Dependent Claim
167 words
A main transmission station for use at the junction of a pair of ungrounded coaxial transmission cables having repeaters therein, and a pair of coaxial transmission cables having grounded outer shields said station comprising, a first capacitor means for coupling between the respective inner conductors of said grounded and ungrounded cables and a second capacitor means for coupling between the respective outer shields of said grounded and ungrounded cables, whereby low-frequency cross-talk can occur due to significant voltages developed across the capacitor means coupled to the outer shields of said ungrounded cables, a pair of direct current source means for supplying the repeaters in said ungrounded cables, a pair of high frequency stop filter means for coupling said source means to said ungrounded cables respectively, each of said filters having a parallel capacitor, a pair of low frequency signal sources, and a pair of means for coupling said low frequency sources to said ungrounded cables respectively, said coupling means each including bridge means for suppressing said cross-talk.
Claim 3
Dependent Claim
96 words
Transmission station as claimed in claim 1, wherein each of said means for suppressing the low-frequency cross-talk comprises the series combination of first and second impedances, said first impedance including the parallel combination of a resistor and a capacitor, said second impedance including the series combination of a resistor and a grounded capacitor, the outputs of said low-frequency sources each including a transformer respectively coupled to the junction point of the said first and second impedances, the other ends of the said first impedances are respectively coupled to the outer conductor of the ungrounded coaxial cables.
Claim 4
Dependent Claim
87 words
Transmission station as claimed in claim 2, wherein the resistors which form part of the said first and second impedances each are equal to the characteristic impedance of the ungrounded and grounded coaxial cables respectively, the capacitor which forms part of the first impedance is equal to the parallel capacitor of the respective high-frequency stop filter, and the capacitor which forms part of the said second impedance is equal to the capacitor coupled between the inner conductor of the respective grounded coaxial cable and the main station.
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) | 1980-05-16 | 1980-11-15 | 1981-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-16 | 1984-11-15 | 1985-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-16 | 1988-11-15 | 1989-05-17 | $7700.00 | Window Closed / Lapsed |