Autopsy:

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from Wikipedia:

The Speak & Spell line is a series of electronic handheld educational toys created by Texas Instruments that consist of a speech synthesizer, a keyboard, and a receptor slot to receive one of a collection of ROM game library modules (collectively covered under US patent 3934233 ).

The first Speak & Spell was introduced at the summer Consumer Electronics Show in June 1978, making it one of the earliest handheld electronic devices with a visual display to use interchangeable game cartridges.

The Speak & Spell was created by a small team of engineers led by Paul Breedlove, himself an engineer, with Texas Instruments (TI) during the late 1970s. Development began in 1976 with an initial budget of $25,000, as an outgrowth of TI’s research into speech synthesis.

The completed proof version of the first console utilized TI’s trademarked Solid State Speech technology to store full words in a solid state format similar to the manner in which calculators of the time stored numbers. Additionally purchased cartridges (called expansion modules) could be inserted behind the battery receptacle to provide new solid state libraries and new games.

This represented the first time an educational toy utilized speech that was not recorded on tape or phonograph record (as with Mattel’s See ‘n Say line or the earlier Chatty Cathy dolls).

source: wikipedia speaknspell.co.uk