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US4987391A Expired / Lapsed US ⏱️ 0.0 years remaining

Antenna cable ground isolator

Assignee: Individual
•
Filing: 1990-03-14
•
Granted: 1991-01-22
•
Expires: 2010-03-14
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Abstract

Abstract A coaxial cable isolator is presented which serves to reduce or eliminate ground loop induced hum and interference in audio-video entertainment systems connected to externally grounded antenna signal sources. A linearly arranged array of discrete monolithic capacitive elements couples two ground plane areas fabricated on a circuit board, which are connected respectively to the shield conductors of the input and output coaxial cables between which DC and audio frequency isolation is desired. Resistive elements are provided for the dissipation of accumulated static charges, and a gas discharge transient suppressor protects equipment connected to the isolator's output from voltages induced by nearby lightning strikes.

Inventors

  • 👤 Michael Kusiak, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 22:22
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/004

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 120 words
A coaxial cable isolator comprising: an area of conductive input ground plane electrically connected to the shield conductor of an input coaxial cable to said isolator; an area of conductive output ground plane electrically connected to the shield conductor of an output coaxial cable to said isolator; said input and output ground planes being separated and thereby electrically isolated from each other by a nonconducting gap; a plurality of capacitive elements placed adjacent to one another in a substantially continuous fashion, bridging said gap over a considerable portion of its extent, thereby constituting a capacitive coupling across said gap; and a coupling means electrically connected between the respective inner conductors of said input and output coaxial cables to said isolator.
Claim 2
Dependent Claim 120 words
A coaxial cable isolator comprising: an area of conductive input ground plane electrically connected to the shield conductor of an input coaxial cable to said isolator; an area of conductive output ground plane electrically connected to the shield conductor of an output coaxial cable to said isolator; said input and output ground planes being separated and thereby electrically isolated from each other by a nonconducting gap; a plurality of capacitive elements placed adjacent to one another in a substantially continuous fashion, bridging said gap over a considerable portion of its extent, thereby constituting a capacitive coupling across said gap; and a coupling means electrically connected between the respective inner conductors of said input and output coaxial cables to said isolator.
Claim 3
Dependent Claim 27 words
The coaxial cable isolator of claim 1 wherein said coupling means between said input coaxial inner conductors comprises a capacitor providing direct current and audio frequency isolation.
Claim 4
Dependent Claim 31 words
The coaxial cable isolator of claim 1 further comprising means for the dissipation of static charges accumulated on said input and output coaxial cables and internal capacitive elements of said isolator.
Claim 5
Dependent Claim 26 words
The coaxial cable isolator of claim 1 further comprising means for high voltage transient suppression, for the protection of equipment connected to said output coaxial cable.
Claim 6
Dependent Claim 30 words
The coaxial cable isolator of claim 1 further comprising a conductive enclosure electrically connected to one of said input or output coaxial shield conductors and electrically isolated from the other.
Claim 7
Dependent Claim 113 words
A coaxial cable isolator comprising: a circuit board clad with conductive material arranged in such a manner whereby the input and output coaxial shield conductors of a coaxial cable are electrically connected to respective conducting ground plane areas on said board which are separated by a continuous gap in said conductive material, so as to provide electrical isolation between said input and output shield conductors; a plurality of capacitive elements, placed adjacent to one another in a substantially continuous fashion, bridging said gap over a considerable portion of its extent; and a coupling means situated on said circuit board connected between the input and output coaxial cable inner conductor terminals on said isolator.
Claim 8
Dependent Claim 113 words
A coaxial cable isolator comprising: a circuit board clad with conductive material arranged in such a manner whereby the input and output coaxial shield conductors of a coaxial cable are electrically connected to respective conducting ground plane areas on said board which are separated by a continuous gap in said conductive material, so as to provide electrical isolation between said input and output shield conductors; a plurality of capacitive elements, placed adjacent to one another in a substantially continuous fashion, bridging said gap over a considerable portion of its extent; and a coupling means situated on said circuit board connected between the input and output coaxial cable inner conductor terminals on said isolator.
Claim 9
Dependent Claim 31 words
The coaxial cable isolator of claim 6 wherein said coupling means between said input and output coaxial cable inner conductor terminals comprises a capacitor providing direct current and low frequency isolation.
Claim 10
Dependent Claim 39 words
The coaxial cable isolator of claim 6 wherein said coupling means between said input and output coaxial cable inner conductor terminals comprises a microstrip transmission line, situated over ground plane on the opposite planar surface of said circuit board.
Claim 11
Dependent Claim 27 words
The coaxial cable isolator of claim 6 further comprising means for the dissipation of static charges accumulated on said input and output coaxial cables internal capacitive elements.
Claim 12
Dependent Claim 26 words
The coaxial cable isolator of claim 6 further comprising means for high voltage transient suppression for the protection of equipment connected to said output coaxial cable.
Claim 13
Dependent Claim 31 words
The coaxial cable isolator of claim 6 further comprising a conductive enclosure electrically connected to one of said input or output coaxial cable shield conductors and electrically isolated from the other.
Claim 14
Dependent Claim 23 words
The coaxial cable isolator of claim 8 wherein said microstrip transmission line further comprises a capacitor providing direct current and audio frequency isolation.
Claim 15
Dependent Claim 47 words
The coaxial cable isolator of claim 12 further comprising: means for the dissipation of static charges accumulated on said input and output coaxial cables and internal capacitive elements; and means for high voltage transient suppression, for the protection of equipment connected to the output of said isolator.
Claim 16
Dependent Claim 31 words
The coaxial cable isolator of claim 13 further comprising a conductive enclosure electrically connected to one of said input or output coaxial shield conductor terminals and electrically isolated from the other.

References Cited (Backward Citations)

US3393384A Cited
US3617607A Cited
US3908176A Cited
US4267529A Cited
US4399419A Cited
US4370630A Cited
US4559506A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-21 1994-07-23 1995-01-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-21 1998-07-23 1999-01-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-21 2002-07-23 2003-01-22 $7700.00 Window Closed / Lapsed

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