Prague postal time service: clock and sirens – improbable connection

Abstract

The goal of this paper is to present the origin, development, and technical parameters of the Postal Time Service, which was established in the capital of Czechoslovakia – Prague, gradually in the years 1933–1935. It also examines the options for determining “public time” in the period before the establishment of this service. In the second part, the text deals with the question of the use of the Postal Time Service infrastructure as an essential part of the air raid alarm siren system. The emergence of this system will be set in the broader context of the deteriorating security and political situation in Central Europe in the second half of the 1930s. In addition to the technical aspects of the warning system itself, the text will also introduce its author, Prof. František Rieger of the College of Mechanical and Electrical Engineering of the Czech Technical University in Prague, and the practical tests of the device, which took place in 1936 and 1937.

Keywords

• history of technology
• Prague Postal Time Service
• Czechoslovakia
• 1930s
• synchronised clocks
• anti-aircraft sirens