Fröken Ur

Purpose

'Fröken Ur’ has been a reliable source of accurate Swedish local time for over 90 years. The service is aimed at both the general public and professional users who need access to accurate time and frequency.

How does it work?

You can reach the service from Sweden at the phone number 90 510. From abroad, you can reach the service via +46 33 19 05 10.

The current Swedish local time is announced every ten seconds, followed by a beep for precise time indication. The date and year are announced once per minute. The call is terminated after 90 seconds.

The service is directly connected to the Swedish official time scale UTC(SP), which is maintained by RISE using atomic clocks

Technical information

The service can be considered an acoustic 0.1 PPS signal (PPS = pulse per second) with interleaved time indication. The time indicated is based on UTC(SP), which is traceable to UTC and can be used for, for example, calibration of stopwatches. Note that there may be requirements for a user method that describes execution and measurement uncertainty calculation approved by the supervisory authority or equivalent, and that the end user is responsible for this. Calibration against 'Fröken Ur' results in higher measurement uncertainty than equivalent calibration performed in the national metrology institute’s calibration lab.

Any delay and variance in the time indication are dominated by effects from the telephone network. These effects are beyond RISE’s control and should be considered by the end user in cases where these uncertainties may be significant for the application.

The service is sometimes used for marketing purposes for RISE. This means that the spoken messages may periodically differ from the normal ones. Neither the functionality of the service nor the accuracy of the time indication is affected by this