In the late 1960's or early 1970's I came upon the PIP,
constructed by Philips, Holland.
The PIP was a desktop-machine, not unlike an early
Macintosh one-piece desktop computer, but with no
keyboard, and a back projection screen replacing the
The PIP contained a Super-8-cassette still-frame
projector. It advanced to the next frame after one pulse
from a pulse generator. The generator was triggered by
inaudible pulses recorded on an audio compact cassette
player, also integrated into the machine. The audio
cassette, running at normal compact cassette speed, also
contained the audio part of the show, delivering mono
sound to the PIP's built-in speaker.
When a motion picture sequence was needed, the audio
compact cassette player delivered a corresponding sequence
of pulses, at up to, say, 18 frames per second. When no
motion picture was needed there were no pulses, and the
PIP behaved like a slide-projector, displaying individual
frames. It could also show short animated sequences at any
necessary frame rate.
With the PIP, one compact audio cassette and a Super-
8-film cassette could create a slide-and-film-and-audio
show of, say, half an hour.