The Philips EL 3581 was an office dictation machine introduced by Philips (known as Norelco in the US) in 1958 and an early magnetic tape dictation system (not the earliest though, as the Grundig Stenorette and Dictaphone Dictet were launched before it). At the time of its introduction, most dictation systems were using discs or belts onto which grooves were pressed, such as the Dictabelt, SoundScriber and Audograph systems.
Although the EL 3581 uses a cartridge so no threading is required, the tape is housed on two separate 3-inch reels with ¼-inch tape and cine spindle holes suitable for domestic open reel tape recorders. Removing a clip from the cartridge shell allows the reels to be removed.
Like some other dictation machines, the microphone also doubles as a speaker, and contains some tape controls. A foot pedal and external speaker were also available.
Sources / Resources
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