I purchased this one-of-a-kind talking clock in July 2024, for $20 at my favorite charity shop in Downtown Akron. Picture was taken at a friend's house.

Introduced in 1979, the Sharp CT-660 "Talking Time" digital clock is the first consumer-grade talking clock ever made that uses actual speech synthesis (most likely LPC, or linear predictive coding*) as opposed to the electromechanical methods that were used prior. It represents a technological breakthrough, being one of the first clocks to use large-scale integration (LSI) construction, as opposed to the usual method (of the time) of mounting discrete components to a printed circuit board. The CT-660 was sold for $100 in 1979 which, adjusted for inflation, equals $460 as of June 2024. The power source is 2 'AA' batteries.

Pressing the yellow button on the top of the unit will announce the time. The dial on the right side allows you to adjust the speech volume or turn it off altogether. The foot on the bottom opens up to allow access to all of the settings of the clock, including time of day, alarm time, countdown timer of 1, 5, and 30 minute intervals, and stopwatch.

When activated, the alarm plays a short 5-note fanfare, announces the alarm time, and plays a delightful little segment of Luigi Boccherini's minuet. If undisturbed 5 minutes later, it will play the fanfare again, announce the current time and ask you to "please hurry", and the minuet plays again. The CT-660 can also announce the time on every hour, and on every half-hour.

An interesting note: a removable rubber cap on the left side reveals two pins which, if bridged by metal, serve the same function as the yellow button on the top of the unit.


*Linear predictive coding is a type speech synthesis that was used by Texas Instruments for their educational toys like the Speak & Spell and Speak & Math, and also the speech synthesizer cartridge for their TI-99/4A computer, a cartridge that gives a voice to the TI-99 game, Parsec. I previously demonstrated LPC on my Arduino using the Talkie code library.