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A similar time signal from the National Research Council is used by CBC radio services at noon and 1pm ET each day. See NRC time signal.

1 Signal Format

CHU transmits 3 kW signals on 3330 and 14670 kHz, and a 10 kW signal on 7335 kHz. The signal used is amplitude modulatedAmplitude modulation (AM is a method used to modulate a signal, typically using radio. In the case of an analog signal to be sent, the amplitude of the radio wave is modulated to be directly proportional to the value of the analog signal at the time., with the lower sidebandIn radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing energy as a result of the modulation process. While all forms of modulation have sidebands by definition, it is most commonly discusse suppressed ( emission typeThe International Telecommunication Union uses a special system for classifying radio frequency signals. Each type of radio emission is classified according to its bandwidth, method of modulation, nature of the modulating signal, and type of information t H3E). The same information is carried on all three frequencies simultaneously. The actual time signal is a series of 300 ms-long tones, transmitted once per second, on the second. The top of the minute is marked by a half-second-long beep, and the top of the hour is marked with a one second-long beep, followed by nine seconds of silence. Thereafter, every second except for the 29th second past the minute, CHU transmits a 300-millisecond tone. Between one and sixteen seconds past the minute, CHU transmits the difference between UT1 and Coordinated Universal TimeCoordinated Universal Time or UTC also sometimes referred to as Zulu time , the basis for civil time differs by an integral number of seconds from atomic time and a fractional number of seconds from UT1. Time zones around the world are expressed as positi (UTC), in much the same way that the value is transmitted on WWV, but with split tones instead of doubled "ticks". Between 31 and 39 seconds past the minute inclusive, the once-per-second tones are reduced to 10-millisecond "ticks" while a digital time code is transmitted. The digital time code used by CHU is unique, in that it is decodeable by a Bell 103 -compatible modem. At ten seconds before each minute, the once-per-second tones are again cut to 10 milliseconds each, this time while voice announcements of the next minute in UTC, alternating between FrenchFrench le francais la langue francaise is one of the most important Romance languages, outnumbered only by Spanish and Portuguese. French is the 11th most spoken language in the world, spoken by about 77 million people (called Francophones) as a mother to and EnglishThe English language is a West Germanic language, originating from England. It is the third most common "first" language (native speakers), with around 402 million people in 2002. English has lingua franca status in many parts of the world, due to the mil, are transmitted. French announcements are transmitted first on the odd minutes, while English announcements come first on the even minutes.