Standard frequency and time signal service


Standard frequency and time signal service is – according to Article 1.53 of the International Telecommunication Union's Radio Regulations – defined as «A radiocommunication service for scientific, technical and other purposes, providing the transmission of specified frequencies, time signals, or both, of stated high precision, intended for general reception.»
See also:

Classification

In accordance with ITU Radio Regulations variations of this radiocommunication service are classified as follows:

Standard frequency and time signal service
In general this radiocommunication service uses radio stations as follows:
The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations.
In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations which is with-in the responsibility of the appropriate national administration. The allocation might be primary, secondary, exclusive, and shared.
; Example of frequency allocation:

Time signals in use

The following are the known HF time signal stations currently operational.

United States

The Standard Time and Frequency Signal is a Radiocommunication service providing the transmission of specified frequency and time signal, of stated high precision, intended for general reception in the United States and beyond. The radio signals are broadcast on very precise carrier frequencies by the U.S. Naval Observatory and the National Institute of Standards and Technology, formerly the National Bureau of Standards. The technical specification of that particular service is in line to the provisions of the International Telecommunication Union's Radio Regulations