Telenorma (Telefonbau und Normalzeit) telecommunications equipment

Telefonbau und Normalzeit, commonly known as Telenorma or TN, was a prominent German telecommunications company with a rich history in manufacturing telephone systems and precision timekeeping devices. Founded in 1899 in Frankfurt am Main, the brand became synonymous with high-quality engineering in the European telecommunications sector during the 20th century.

Throughout its history, the company underwent several ownership changes, most notably being acquired by Robert Bosch GmbH in the 1980s. Following this acquisition, it was integrated into Bosch Telecom. Eventually, the enterprise communications division was sold to Kohlberg Kravis Roberts & Co. (KKR) and later integrated into Avaya. Today, the legacy of Telenorma is maintained within the global operations of Avaya, which continues to provide business communication solutions worldwide.