US3913015A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tuned current probe
Assignee: United States Department of the Air Force
•
Filing: 1974-07-26
•
Granted: 1975-10-14
•
Expires: 1994-07-26
Abstract
Abstract High transfer impedance and hence improved sensitivity is achieved in line current measuring apparatus by making the current detecting probe resonant to the frequency of the line conducted signal being measured. The current detecting probes are inductive pick-off coils and resonance is accomplished by means of a variable capacitance circuit connected in parallel with the pick-off coils. The parallel resonant circuit drives a high input impedance low output impedance amplifier. A broad band signal measuring system employs multiple probes each of which has a frequency range that covers a portion of the system operating frequency range. The circuit of the highest frequency probe is balanced and utilizes back-to-back series connected voltage variable capacitance diodes in its variable capacitance circuit.
Inventors
- 👤 Edwin L Bronaugh
- 👤 Roger A Southwick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:11
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/145; G01R19/15
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
66 words
A current probe for detecting the current value of a line conducted electrical signal comprising an inductive pick-off coil adapted for electromagnetic coupling to said line conducted electrical signal, and tuning means for tuning said inductive pick-off coil to resonate at the line conducted electrical signal frequency, said tuning means including at least one voltage variable capacitance diode connected in parallel with said inductive pick-off coil.
Claim 2
Dependent Claim
66 words
A current probe for detecting the current value of a line conducted electrical signal comprising an inductive pick-off coil adapted for electromagnetic coupling to said line conducted electrical signal, and tuning means for tuning said inductive pick-off coil to resonate at the line conducted electrical signal frequency, said tuning means including at least one voltage variable capacitance diode connected in parallel with said inductive pick-off coil.
Claim 3
Dependent Claim
54 words
A current probe as defined in claim 1 wherein said inductive pick-off coil comprises first and second series connected toroidal coils, and said tuning means includes first and second back-to-back series connected voltage variable capacitance diodes, said toroidal coils being connected in parallel with said voltage variable capacitance diodes in a balanced circuit configuration
Claim 4
Dependent Claim
135 words
A tuned current probe system for detecting the current value of a line conducted electrical signal including a multiplicity of current probes each said probe comprising an inductive pick-off coil adapted for electromagnetic coupling to said line conducted electrical signal, and tuning means for tuning said inductive pick-off coil to resonate at the line conducted electrical signal frequency, the discrete frequency ranges of the individual probes comprising contiguous substantially octave increments of the system operating frequency range, the upper frequency increment probe having an inductive pick-off coil comprising first and second series connected toroidal coils, said upper frequency increment probe further having a tuning means that includes first and second back-to-back series connected voltage variable capacitance diodes, said toroidaL coils being connected in parallel with said voltage variable capacitance diodes in a balanced circuit configuration.
Claim 5
Dependent Claim
135 words
A tuned current probe system for detecting the current value of a line conducted electrical signal including a multiplicity of current probes each said probe comprising an inductive pick-off coil adapted for electromagnetic coupling to said line conducted electrical signal, and tuning means for tuning said inductive pick-off coil to resonate at the line conducted electrical signal frequency, the discrete frequency ranges of the individual probes comprising contiguous substantially octave increments of the system operating frequency range, the upper frequency increment probe having an inductive pick-off coil comprising first and second series connected toroidal coils, said upper frequency increment probe further having a tuning means that includes first and second back-to-back series connected voltage variable capacitance diodes, said toroidaL coils being connected in parallel with said voltage variable capacitance diodes in a balanced circuit configuration.
References Cited (Backward Citations)
US3356939A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |