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