It used to be that time was a lot more relative than it is today. With smartphones synced to GPS and network providers’ clocks, we all pretty much have access to an authoritative current time, giving few of us today the wiggle room to explain a tardy arrival at work to an impatient boss by saying our watch is running slow.
Even when that excuse was plausible, it was a bit weak, since almost every telephone system had some sort of time service. The correct time was but a phone call away, announced at first by live operators then later by machines called speaking clocks. Most of these services had been phased out long ago, but one, the speaking clock service in Australia, sounded for the last time at the end of September.
While the decommissioned machine was just another beige box living in a telco rack, the speaking clocks that preceded it were wonderfully complex electromechanical devices, and perfect fodder for a Retrotechtacular deep-dive. Here’s a look at the Australian speaking clock known as “George” and why speaking clocks were once the highest of technology.
Worst Job Ever
While we laugh – or cry – at stories today of the idiotic things people call emergency service numbers like 911 for, such behavior is far from new and at least somewhat understandable. People have always had a need for authoritative answers to simple questions, and one of the most common question fielded by operators in the early days of the telephone network was, “What time is it?” At first, the number of subscribers on any system was low enough that queries like that didn’t cause a problem, but network growth made it increasingly costly, since an operator telling someone the time wasn’t connecting a profitable call.
Telephone companies reacted to this by assigning one operator to time requests. Sitting at a special station, she – operators were invariably female – would read the time over and over on a special circuit, which people would connect to using a dedicated number. It had to be the most boring job in the world, so much so that operators rotated between regular duties and the time announcement station.
But as we see today, automation eventually threatens every job, and by the 1930s the technology for recording and playing back the human voice had progressed to the point where a “speaking clock” was feasible. The first speaking clock telephone service was installed in Paris in 1933, using optically recorded voice snippets that would form the core of most speaking clocks for the next 30 years.
Voice on Glass
While the French l’horloge parlante used glass cylinders, most speaking clocks would record the voice clips on three glass discs. The soundtracks were very similar to the optical soundtracks used in cinema at the time, and were read from the discs using photocell vacuum tubes, just like movie projectors. The discs rotated at a stately speed on a common shaft, driven by an electric motor that was synchronized to a time standard. AC mains frequency was nowhere near precise enough for this application, so external time standards ranging from precision pendulums to atomic clocks were used to control the motor speed.
In the Australian clock, each announcement was composed of phrases recorded separately and stored on different parts of the three optical discs. A series of cams and followers moved the photocells to the correct position on each disc to pick up the correct phrase, composing the message for the current time. Each announcement started with “At the third stroke, the time will be…” The mechanism then switched to a different disc to add the hour, then again to add the minute. Finally, the upcoming 10-second interval was called out, followed by three pips at one-second intervals. So the entire message might be, “At the third stroke, the time will be twelve twenty-three and 40 seconds; pip – pip – pip.” At the top of each minute, the word “precisely” was substituted for the seconds, projecting the appropriate air of confidence users were to have in the accuracy of the system.
With the Utmost Care
The video below shows the original 1954 installation of the first speaking clocks installed in Australia. The film is a classic bit of corporate showmanship and a time capsule of telephone operations in the Post War era. The two speaking clocks were a monstrous undertaking, being delivered by ship in 37 crates each and painstakingly installed in Melbourne and Sydney simultaneously. We’re told that every step was performed “under the supervision of Post Office engineers” – as in England at the time, telephone services were provided under the auspices of the post office.
The care that went into these devices was apparently well worth it; not only did the phone companies a lot of money with them, but they also managed to stay in service for decades. The Australian electromechanical clocks remained on the job until 1966, at which time they were replaced with machines using magnetic recordings. Those remained in service until replaced with fully digital speaking clocks in 1990, which were the units that were retired only last month.
It’s a little sad but understandable to see devices like these, especially the mechanical ones, retired. There’s something remarkably satisfying about hearing those machines in action — not just the perfect diction of the carefully chosen speakers but the clicks and clacks of the mechanism as it goes through its motions. It’s a pity that the world doesn’t need such brilliant engineering anymore, but at least a few examples live on in museums today.
Thanks to [macsimski] for the tip.
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