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US4099217A Expired / Lapsed US ⏱️ 0.0 years remaining

Protection circuits

Assignee: Post Office
•
Filing: 1977-02-11
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Granted: 1978-07-04
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Expires: 1997-02-11
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Abstract

Abstract A surge protection circuit for repeaters in a co-axial telecommunications cable where the power supply is through the cable conductors includes a cold-cathode discharge tube connected so as to provide a discharge path, when a surge occurs, for a capacitor through the power tapping resistor so that the discharge current through the power tapping resistor is in opposition to the normal current through the resistor.

Inventors

  • 👤 Kenneth David Fitchew

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:03
CPC Classifications
H; H02; H02H; H02H9/00; H02H9/04

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 68 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor in series with a first conductor of said cable, said surge protection circuit comprising a voltage sensitive discharge means effectively connected in parallel with said power-tapping resistor and further comprising a capacitor connected directly between one terminal of said power-tapping resistor and earth.
Claim 2
Dependent Claim 68 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor in series with a first conductor of said cable, said surge protection circuit comprising a voltage sensitive discharge means effectively connected in parallel with said power-tapping resistor and further comprising a capacitor connected directly between one terminal of said power-tapping resistor and earth.
Claim 3
Dependent Claim 20 words
A surge protection circuit as claimed in Claim 1 in which said voltage-sensitive discharge means is a cold-cathode discharge tube.
Claim 4
Dependent Claim 108 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor in series with a first conductor of said cable and wherein there is additionally power separating filters in series with the first conductor of said cable wherein said surge protection circuit comprises voltage sensitive discharge means connected in parallel with the series combination of said power-tapping resistor and a power separating filter, said surge protection circuit further comprising a capacitor connected directly between the end of said power-tapping resistor remote from the end thereof connected to said voltage sensitive discharge means and earth.
Claim 5
Dependent Claim 108 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor in series with a first conductor of said cable and wherein there is additionally power separating filters in series with the first conductor of said cable wherein said surge protection circuit comprises voltage sensitive discharge means connected in parallel with the series combination of said power-tapping resistor and a power separating filter, said surge protection circuit further comprising a capacitor connected directly between the end of said power-tapping resistor remote from the end thereof connected to said voltage sensitive discharge means and earth.
Claim 6
Dependent Claim 20 words
A surge protection circuit as claimed in claim 3 in which said voltage-sensitive discharge means is a cold-cathode discharge tube.
Claim 7
Dependent Claim 101 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor having a first and a second end in series with the first conductor of said cable, wherein a voltage sensitive discharge means is connected between the first end of said power-tapping resistor and a point on the first conductor of said cable adjacent the input to the repeater remote from the first end of said power-tapping resistor, said surge protection circuit further comprising a capacitor connected between the second end of said power-tapping resistor and earth.
Claim 8
Dependent Claim 101 words
A surge protection circuit for a telecommunications cable repeater of the type wherein a voltage supply for the repeater is derived from a power-tapping resistor having a first and a second end in series with the first conductor of said cable, wherein a voltage sensitive discharge means is connected between the first end of said power-tapping resistor and a point on the first conductor of said cable adjacent the input to the repeater remote from the first end of said power-tapping resistor, said surge protection circuit further comprising a capacitor connected between the second end of said power-tapping resistor and earth.
Claim 9
Dependent Claim 21 words
A surge protection circuit as claimed in claim 5 in which said voltage sensitive discharge means is a cold-cathode discharging tube.

References Cited (Backward Citations)

GB1037958A Cited
US3644787A Cited
DE2508283A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-07-03 1982-01-02 1982-07-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-07-03 1986-01-02 1986-07-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-07-03 1990-01-02 1990-07-04 $7700.00 Window Closed / Lapsed

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