You are here: Home USNO Precise Time Telephone Time
The USNO websites aa.usno.navy.mil, ad.usno.navy.mil, aristarchus.usno.navy.mil, maia.usno.navy.mil, rorf.usno.navy.mil, and toshi.usno.navy.mil are undergoing modernization efforts. The expected completion of the work and return of service is estimated as 30 April 2020. Please submit a requirements form to the USNOPAO if the information you are seeking is not accessible via other means.
 

Telephone Time

USNO provides both voice announcements of the time, and services to synchronize systems over telephone modems.

Voice Announcers

The voice announcements have the same pattern at both sites, and always begin with the local time (daylight or standard). The local time announcements are made on the minute, and 15, 30, and 45 seconds after the minute. Coordinated Universal Time (UTC) is announced five seconds after the local time.

Time may be delayed on long distance calls.

Time Voice Announcer, Washington, DC:       

  • 202-762-1401
  • 202-762-1069
  • DSN 762-1401
  • DSN 762-1069

Time Voice Announcer, Colorado Springs, CO:

  • 719-567-6742 
  • DSN 560-6742

Digital Time for MODEMS

These MODEMS operate at 1200 baud, 8N1 only.

From Washington, DC:           

  • 202-762-1594
  • DSN 762-1594

From Colorado Springs, CO:      

  • 719-567-6743
  • DSN 560-6743
USNO Master Clock Time
Javascript must be Enabled