![]() ![]() The civil time code generators and two tone generators were designed and built within TRL. Design 2000 incorporated TRL oscillators in the phase locked oscillator units designed at TRL and controlled by two tone from the Telstra Caesium beam frequency standards. Assmann Australia used a German announcing unit and built a supervisory unit to TRL specifications. The various components were sent for commercial production after a working prototype was built in the Telstra Research Laboratory (TRL). The voice was provided by Richard Peach, a former ABC broadcaster. Each speaking clock ensemble consisted of two announcing units (Zag 500), a supervisory unit (CCU 500), two phase-locked oscillators, two pulse distribution units, a Civil Time Receiver (plus a spare), and two or four Computime 1200 baud modems. This mechanical system was replaced with a digital system in 1990. Building M5), the control signals were duplicated and a second bank of Caesium Beam Primary standards installed so the cutover was transparent with no loss of service.Īssmann digital speaking clock at the Victorian Telecommunications Museum When Time & Frequency Standards moved from 59 Collins Street to Clayton Research Labs (3rd Flr. From a maintenance point of view, the most important part of the mechanical clocks was to ensure that they were well oiled to minimise wear on the cams and to replace blown bulbs in the optical pickups from the glass disk recordings. The Time and Frequency Standards Section in the PMG Research Laboratories at 59 Little Collins Street, Melbourne maintained the frequency checks to ensure that the system was "on time". In addition to the speaking clocks, there was ancillary equipment to provide timing signals, 1 pulse per second, 8 pulses per minute and 8 pulses per hour. For daylight saving time changes, one would be on line while the second was advanced or delayed by one hour and at the 02:00:00 Australian Eastern Standard time, would be switched over to the standby unit. ![]() Both units in Melbourne and Sydney were run in tandem (primary and backup). The units were designed for continuous operation. Because of the low torque available, a hand wheel was used to spin the motor on start up. This was amplified to give sufficient impetus to drive the motor. A synchronous motor drove the disc with the driving source derived from a 5 MHz quartz oscillator via a multi stage valve divider. The mechanical speaking clock used rotating glass discs where different parts of the time were recorded on the disc. In 1954, British-made systems were installed in Melbourne (1st floor, City West Exchange) and Sydney. This was not precise and the operator could not always answer when the subscriber wanted. Prior to automatic systems, the subscriber rang an operator who would quote the time from a central clock in the exchange with a phrase such as "The time by the exchange clock is ……". Mechanical speaking clock at the Victorian Telecommunications Museum ![]() Originally there was only one stroke e.g.:“At the stroke, it will be……” etc. The time announcement was announced in 10 second increments and the beep was 1 kHz. "At the third stroke, it will be three thirty three and forty seconds". A male voice, often known by Australians as "George", would say "At the third stroke, it will be (hours) (minutes) and (seconds) seconds/precisely. ![]() Landline, Payphone and Mobile customers who called the 1194 time service would receive the time. It was always the current time from where the call originated, in part due to Telstra's special call routing systems. The service started in 1953 by the Post Master General's Department, originally to access the talking clock on a rotary dial phone, callers would dial "B074", during the transition from a rotary dial to a DTMF based phone system, the talking clock number changed from "B074" to 1194. In Australia, the number 1194 was the speaking clock in all areas. Some countries have sponsored time announcements and include the sponsor's name in the message. ten seconds) a voice announces (for example) "At the third stroke, the time will be twelve forty-six and ten seconds……", with three beeps following. The format of the service is similar to that of radio time signal services. The first telephone speaking clock service was introduced in France, in association with the Paris Observatory, on 14 February 1933. Time of day voice service A human speaking clock prior to the introduction of automated equipment, October 1937 Newspaper notice (1918) warning telephone subscribers that New England Telephone & Telegraph Company operators will soon refuse to provide time of day on subscriber request.Ī speaking clock or talking clock is a live or recorded human voice service, usually accessed by telephone, that gives the correct time. ![]()
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