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US 2956114Freedom to Build
Public domain since 1977

You can freely build on How Ampex Invented Modern Video Recording on Magnetic Tape

This patent expired in 1977. Every claim — 0 independent, 0 dependent — is now unenforceable. Anyone can use, reproduce, manufacture, sell, or offer for sale this technology without a license.

Original assignee

Ampex Corp

Patent granted

1960

Expired

1977

Forward citations

11

What this patent covers

The system uses a rotating head assembly that spins at high speeds perpendicular to the direction of the moving magnetic tape. By scanning the tape transversely, the system achieves the high relative speeds necessary to capture the massive amount of data required for a television signal. This allows for the storage of high-frequency video information on a relatively slow-moving strip of tape. It effectively solved the problem of how to record a signal that required a bandwidth far beyond what stationary heads could handle at the time.

What is now free to use

All 0 claims of US 2956114 are in the public domain. Specifically:

    The 0 dependent claims add narrowing limitations and are also free.

    What is NOT covered

    Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.

    • Does not cover digital video recording or compression formats.

    • Does not cover helical scan recording, which uses a different tape path geometry.

    • Does not cover optical disc storage or solid-state memory.

    Who is building on this today

    Ampex pioneered this space, and their technology served as the foundation for the entire broadcast video industry. Modern digital storage companies and archival systems continue to trace their lineage back to these fundamental magnetic recording principles.

    Products built on expired version of this technology

    Ampex VR-1000 broadcast video tape recorder

    Early television studio master recording equipment

    How to cite this patent in your documentation

    Ampex Corp. US Patent 2956114. Broad band magnetic tape system and method. Granted 1960, expired 1977. Now in the public domain.

    Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.

    PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.

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