History

TN stands for Telefonbau & Normalzeit Hamburg Germany H. Fuld & Co. Telephon und Telegraphenbau GmbH was founded in 1901 as an independent subsidiary for the production of extension sets because the devices originally purchased from Bell Company in Antwerp proved not to be very reliable. In 1913 a new branch of business was established, which was strictly separated from telephony, the production and rental of remote-controlled, electric clocks. In 1937 the company was renamed Telefonbau und Normalzeit Lehner & Co.