US3871024A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Video transducer system with magnetic transducer head having output winding means resonant at a mid band resonance frequency
Assignee: IIT Research Institute
•
Filing: 1973-06-15
•
Granted: 1975-03-11
•
Expires: 1993-06-15
Abstract
Abstract A wideband transducer system including longitudinally recorded video, transversely recorded or multiplexed audio, channel shifting during blanking intervals, high frequency bias synchronized to audio carrier frequency or otherwise selected to avoid beat notes, head with plural windings switched to reduce inductance during recording and connected for wideband playback into an amplifier input with comparable or higher impedance than that of the winding.
Inventors
- 👤 Marvin Camras
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:18
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/92; H04N5/921; G; G11; G11B; G11B5/00; G11B5/127
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
253 words
A video transducer system for the transmission of video intelligence comprising: a magnetic transducer head having output winding means resonant at a mid band resonance frequency, said head having coupling means for coupling to a magnetic record medium to receive input frequency components both above and below said mid band resonance frequency and producing at the output winding means corresponding output frequency components having a substantial phase error therebetween in comparison to the relative phase of said input frequency components, the input frequency components extending over a wide bandwidth with the frequency range from the lowest essential frequency component to the highest essential frequency component for transmission of the video intelligence extending over many octaves, and signal translating means having an input coupled to said output winding means and having an input impedance at said mid band resonance frequency at least substantially comparable to the impedance of said output winding means to receive a characteristic substantially increasing amplitude as a function of frequency from the output winding means in the neighborhood of said mid band resonance frequency, said signal translating means having an output, and having a compensating circuit interposed between the input and output thereof to substantially equalize the shifts in phase produced between said head coupling means and said output over a substantial range of frequencies including frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency to essentially compensate for such phase error over the wide bandwidth of the video intelligence being transmitted.
Claim 2
Dependent Claim
253 words
A video transducer system for the transmission of video intelligence comprising: a magnetic transducer head having output winding means resonant at a mid band resonance frequency, said head having coupling means for coupling to a magnetic record medium to receive input frequency components both above and below said mid band resonance frequency and producing at the output winding means corresponding output frequency components having a substantial phase error therebetween in comparison to the relative phase of said input frequency components, the input frequency components extending over a wide bandwidth with the frequency range from the lowest essential frequency component to the highest essential frequency component for transmission of the video intelligence extending over many octaves, and signal translating means having an input coupled to said output winding means and having an input impedance at said mid band resonance frequency at least substantially comparable to the impedance of said output winding means to receive a characteristic substantially increasing amplitude as a function of frequency from the output winding means in the neighborhood of said mid band resonance frequency, said signal translating means having an output, and having a compensating circuit interposed between the input and output thereof to substantially equalize the shifts in phase produced between said head coupling means and said output over a substantial range of frequencies including frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency to essentially compensate for such phase error over the wide bandwidth of the video intelligence being transmitted.
Claim 3
Dependent Claim
253 words
A video transducer system for the transmission of video intelligence comprising: a magnetic transducer head having output winding means resonant at a mid band resonance frequency, said head having coupling means for coupling to a magnetic record medium to receive input frequency components both above and below said mid band resonance frequency and producing at the output winding means corresponding output frequency components having a substantial phase error therebetween in comparison to the relative phase of said input frequency components, the input frequency components extending over a wide bandwidth with the frequency range from the lowest essential frequency component to the highest essential frequency component for transmission of the video intelligence extending over many octaves, and signal translating means having an input coupled to said output winding means and having an input impedance at said mid band resonance frequency at least substantially comparable to the impedance of said output winding means to receive a characteristic substantially increasing amplitude as a function of frequency from the output winding means in the neighborhood of said mid band resonance frequency, said signal translating means having an output, and having a compensating circuit interposed between the input and output thereof to substantially equalize the shifts in phase produced between said head coupling means and said output over a substantial range of frequencies including frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency to essentially compensate for such phase error over the wide bandwidth of the video intelligence being transmitted.
Claim 4
Dependent Claim
253 words
A video transducer system for the transmission of video intelligence comprising: a magnetic transducer head having output winding means resonant at a mid band resonance frequency, said head having coupling means for coupling to a magnetic record medium to receive input frequency components both above and below said mid band resonance frequency and producing at the output winding means corresponding output frequency components having a substantial phase error therebetween in comparison to the relative phase of said input frequency components, the input frequency components extending over a wide bandwidth with the frequency range from the lowest essential frequency component to the highest essential frequency component for transmission of the video intelligence extending over many octaves, and signal translating means having an input coupled to said output winding means and having an input impedance at said mid band resonance frequency at least substantially comparable to the impedance of said output winding means to receive a characteristic substantially increasing amplitude as a function of frequency from the output winding means in the neighborhood of said mid band resonance frequency, said signal translating means having an output, and having a compensating circuit interposed between the input and output thereof to substantially equalize the shifts in phase produced between said head coupling means and said output over a substantial range of frequencies including frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency to essentially compensate for such phase error over the wide bandwidth of the video intelligence being transmitted.
Claim 5
Dependent Claim
69 words
The transducer system of claim 1 with said winding means comprising two windings connected in a true series circuit with respect to the lowest frequencies of the bandwidth during playback operation, one of said windings predominating at said mid band resonance frequency of said winding means and the other of said windings predominating at a higher resonance frequency of said winding means near the upper end of the bandwidth.
Claim 6
Dependent Claim
30 words
The transducer system of claim 1 with said output winding means comprising a higher turns winding and a lower turns winding, said windings having a turns ratio of about three-to-one.
Claim 7
Dependent Claim
33 words
The transducer system of claim 1 with said winding means comprising a pair of windings, means for connecting said windings in series during playback, and means for reducing head inductance during recording operation.
Claim 8
Dependent Claim
53 words
The transducer system of claim 1 with said winding means comprising a higher turns winding and a lower turns winding, the higher turns winding having a shunt resistor connected thereacross with a resistance of substantial magnitude in comparison to the inductive reactance of the higher turns winding at said mid band resonance frequency.
Claim 9
Dependent Claim
64 words
The transducer system of claim 5 with said signal translating means comprising a playback amplifier having its input connected to said widings in series aiding relation, said shunt resistor having a resistance value lower than the input impedance of the playback amplifier at the mid band resonance frequency but of a substantial magnitude in comparison to the inductive reactance of the higher turns winding.
Claim 10
Dependent Claim
35 words
The transducer system of claim 1 with said winding means comprising windings connected in a true series circuit and in aiding relation with respect to frequencies below said mid band resonance frequency during playback operation.
Claim 11
Dependent Claim
24 words
The transducer system of claim 7 with said winding means conprising windings with different resonant frequencies, and having a turns ratio of about three-to-one.
Claim 12
Dependent Claim
47 words
The transducer system of claim 1 wherein said winding means comprising a pair of windings, means for effectively energizing only one of said windings during recording, and means for connecting said windings in series during playback with a resistor operatively connected across the one of said windings.
Claim 13
Dependent Claim
59 words
The transducer system of claim 9 with said windings having a turns ratio of about three-to-one, and said resistor being connected across the winding with the higher number of turns and having a resistance comparable to the inductive reactance of the higher turns winding at the mid band resonance frequency, the other lower turns winding being used during recording.
Claim 14
Dependent Claim
178 words
A video playback system operable over a wide bandwidth comprising a playback head having output winding means resonant at a mid band resonance frequency, said output winding means having said mid band resonance frequency located at a mid band frequency at least two octaves below the highest essential frequency component of said wide bandwidth, said head having input means for receiving input frequency components both above and below said mid band resonance frequency, and producing at the output winding means corresponding output frequency components, and signal translating means having an input coupled to said output winding means for receiving said corresponding output frequency components therefrom, having an output, and having a compensating circuit interposed between the input and output thereof for tending to equalize the shifts in phase introduced between said head input means and said output between frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency, and being operable to supply output frequency components of effective amplitude at frequencies at least two octaves above said mid band resonance frequency.
Claim 15
Dependent Claim
178 words
A video playback system operable over a wide bandwidth comprising a playback head having output winding means resonant at a mid band resonance frequency, said output winding means having said mid band resonance frequency located at a mid band frequency at least two octaves below the highest essential frequency component of said wide bandwidth, said head having input means for receiving input frequency components both above and below said mid band resonance frequency, and producing at the output winding means corresponding output frequency components, and signal translating means having an input coupled to said output winding means for receiving said corresponding output frequency components therefrom, having an output, and having a compensating circuit interposed between the input and output thereof for tending to equalize the shifts in phase introduced between said head input means and said output between frequency components below said mid band resonance frequency and frequency components above said mid band resonance frequency, and being operable to supply output frequency components of effective amplitude at frequencies at least two octaves above said mid band resonance frequency.
Claim 16
Dependent Claim
26 words
The playback system of claim 11 with said winding means comprising two windings connected in true series circuit and having a turns ratio of about five-to-one.
Claim 17
Dependent Claim
48 words
The playback system of claim 11 with said winding means comprising windings with different resonance frequencies, one resonant at said mid band resonance frequency and the other at a higher resonance frequency, such that the ratio of the resonance frequencies is in the range from five-to-one to ten-to-one.
Claim 18
Dependent Claim
55 words
The playback system of claim 11 with said winding means comprising a lower turns winding and a higher turns winding, means for effectively energizing only the lower turns winding during recording, and for connecting said windings in series during playback with a resistor of at least about 3000 ohms connected across said higher turns winding.
Claim 19
Dependent Claim
33 words
The playback system of claim 11 with said winding means comprising a pair of windings, means for connecting said windings in series during playback, and means for reducing head inductance during recording operation.
Claim 20
Dependent Claim
17 words
The playback system of claim 15 with means for connecting the windings in parallel during recording operation.
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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |