Official National Sources of Time NTP Canada: NRC Japan: NICT Germany: PTB United Kingdom: NPL United States: NIST, USNO Long Wave Japan: JJY: 60 KHz and 40 KHz Germany: DCF77: 77.5 KHz United Kingdom: MSF: 60 KHz United States: WWVB: 60 KHz Short Wave Canada: NRC, CHU: 3330, 7850, and 14,670 kHz United States: NIST, WWV: 2.5, 5, 10, 15, and 20 MHz
