The instrument
Eko probably launched the Rhythmiker and the much simpler Rhythmbox at the same time in 1972. The Rhythmiker has 16 patterns and 7 rhythm instruments that can be mixed.
Details
The Rhythmaker has the adjustable 7 patterns snare, timbale, clave, charleston, cymbal, block and bass. The 16 presets are march, slowrock, foxtrot, rock, shuffle, bossanova, jazz, samba, swing, mambo, chacha, waltz, beguine, western, rhumba and tango. There are also controls for volume, sustain and tempo.