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US3760123A Expired / Lapsed US ⏱️ 0.0 years remaining

Efficient direct contact transfer of long wavelength signals

Assignee: Individual
•
Filing: 1972-04-07
•
Granted: 1973-09-18
•
Expires: 1992-04-07
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Abstract

Abstract A selected signal track on a master magnetic tape having other signal tracks is direct contact transferred to a copy tape. The portion of the copy tape in line with the selected signal track is magnetically biased by magnetic lines of force emanating from a high permeability magnetic structure. This structure is spaced from the copy tape a predetermined amount sufficient to prevent dispersal of the longest wavelength magnetic signals on the master tape but close enough to localize the magnetic bias on the copy tape for efficient signal transfer only of the selected signal track.

Inventors

  • 👤 P Smaller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 09:36
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/86; G11B5/865

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 134 words
Apparatus for the contact transfer of a selected signal track containing audio signals of longest wavelength lambda l from a master magnetic storage medium having other signal tracks to a copy magnetic storage medium, said apparatus comprising: means for maintaining said master and copy storage mediums in substantially slippage-free contact; means for magnetically biasing said copy storage medium in line with said selected signal track during the contact transfer, said magnetic biasing means including a high permeability magnetic structure spaced from the copy storage medium at least 0.1 lambda l to prevent dispersal by said magnetic structure of the longest wavelength magnetic signals on said selected signal track and no more than 0.3 lambda l to localize the magnetic bias on said copy storage medium for efficient transfer only of said selected signal track.
Claim 2
Dependent Claim 134 words
Apparatus for the contact transfer of a selected signal track containing audio signals of longest wavelength lambda l from a master magnetic storage medium having other signal tracks to a copy magnetic storage medium, said apparatus comprising: means for maintaining said master and copy storage mediums in substantially slippage-free contact; means for magnetically biasing said copy storage medium in line with said selected signal track during the contact transfer, said magnetic biasing means including a high permeability magnetic structure spaced from the copy storage medium at least 0.1 lambda l to prevent dispersal by said magnetic structure of the longest wavelength magnetic signals on said selected signal track and no more than 0.3 lambda l to localize the magnetic bias on said copy storage medium for efficient transfer only of said selected signal track.
Claim 3
Dependent Claim 35 words
Apparatus as in claim 1 wherein the longest wavelength lambda l of said audio signals is approximately 40 mils and said magnetic structure is spaced between 4 mils and 12 mils from said copy tape.
Claim 4
Dependent Claim 66 words
Apparatus as in claim 1 wherein: said master and copy magnetic storage mediums comprise magnetic tapes; said selected siganl track extends in a direction parallel to the longitudinal edge of said tapes; and said other signal tracks are slanted with respect to the side edge of said tapes and terminate adjacent said selected signal track, said other signal tracks containing video signals having relatively short wavelengths.

References Cited (Backward Citations)

US2738383A Cited
US2795651A Cited
US2918537A Cited
US2747026A Cited
US2926219A Cited
US3037090A Cited
US3277244A Cited
US3573390A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-09-17 1977-03-19 1977-09-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-09-17 1981-03-19 1981-09-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-09-17 1985-03-19 1985-09-18 $7700.00 Window Closed / Lapsed

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