Telechron Documents
This page provides access to historical documents related to the Telechron company, its founder Henry Ellis Warren, and the development of synchronous electric timekeeping. These documents offer valuable insight into the technology, business, and vision behind one of the most important innovations in twentieth-century timekeeping.
Documents Collection
- Henry Warren Biography A biographical account of Henry Ellis Warren (1872-1957), the inventor of the synchronous electric clock and founder of the Warren Clock Company (later Warren Telechron). Warren's key insight -- that the AC power grid frequency could serve as a universal time standard -- transformed timekeeping from a craft requiring manual winding and regulation into an automated utility.
- Telechron Type A Master Clock -- NAWCC Bulletin Article An article from the National Association of Watch and Clock Collectors (NAWCC) Bulletin describing the Telechron Type A Master Clock in detail. The Type A was the flagship of Telechron's institutional clock line, featuring three dial faces and the ability to drive slave clocks throughout a building.
- Telechron Type B Master Clock Instruction Book The original manufacturer's instruction book for the Telechron Type B Master Clock. This document covers installation, operation, and maintenance procedures for the Type B, which was designed as a more compact alternative to the Type A for smaller institutional installations.
- Modern Electric Clocks -- A Paper by Henry Warren (February 6, 1937) A paper read by Henry Warren in 1937 describing the state of electric clock technology. In this paper, Warren discusses the principles of synchronous motor timekeeping, the relationship between power grid frequency and clock accuracy, and the future of electric timekeeping. This is a primary source document from the inventor himself.
- Central Station -- Electrical World (February 1926) An article from Electrical World magazine dated February 1926, discussing the role of central power stations in maintaining frequency accuracy for synchronous clock systems. This article illustrates the collaboration between clock manufacturers and power utilities that made synchronous timekeeping possible.
- Warren Telechron Presentation A presentation covering the history and technology of the Warren Telechron Company, including the development of the synchronous motor, the company's product line, and its role in American timekeeping.
- Synchronous Clock Patent 1283431 (1918) Henry Warren's 1918 patent (US Patent 1,283,431) for a synchronous clock system. This foundational patent describes the use of a synchronous motor driven by alternating current to keep time, and includes the mechanism for correcting the clock after power interruptions. This patent is one of the most important documents in the history of electric timekeeping.
- Warren Master Clock Patent 1502493 (1924) Henry Warren's 1924 patent (US Patent 1,502,493) for a master clock system. This patent describes improvements to the master clock design, including methods for driving multiple slave clocks from a single master and for correcting slave clocks after power interruptions.
About These Documents
These documents are provided for educational and historical reference. They represent primary sources from the era when synchronous electric timekeeping was developed and deployed across the United States. Researchers, collectors, and horological enthusiasts are welcome to use them for non-commercial purposes.
For additional information about the Telechron clocks in this collection, visit the Telechron Master A Restoration, Telechron Master B, and Telechron Program Clock pages.