Hammond E-100 Tonewheel Organ

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In 1965, the Hammond E-100 appeared on the market as a supplement to older models. It was slightly reduced in its functions with modified electronics, but retained the tonewheel equipment. It was built under licence by Jorgensen in Copenhagen. 
The features are: two keyboards of 5 octaves; two octave radial pedal board; 9 upper drawbars; 16', 5' 1/3, 8', 4', 2' 2/3, 2' ,1' 3/5 ,1' 2/3,. 1'; upper presets String 8', Full Tibias 16' and Theatre Brass 16; upper percussion Chimes, Guitar, Marimba, Xylophone, Banjo; reiteration for Harp Sustain, Add Vibrato, Cymbal Pedal, Brush Lower; 
lower Brush Volume knobs for Vibrato Small, Vibrato  / Chorus, Celeste I, Celeste II, Upper On/Off, Lower On/Off tabs, 9 lower presets 16', 5' 1/3, 8', 4', 2' 2/3, 2' ,1' 3/5 ,1' 2/3,. 1'; lower presets Flutes & Strings 8', Tibias 8', Ensemble 8'; Bass pedal 16' and 8'; Stereo Reverb I and II;
soft volume; all-valve circuits, except transistorized pedal divider and brush / cymbal circuitry; built-in 5-pin Leslie controller. (source: Orgelsurium)

The sound production of the Hammond organ begins in the cogwheel oscillator. Metal tone wheels with a wavy edge rotate in front of electromagnetic pickups (iron cores in coils). The waveform causes the edge of the wheel to periodically move away from and towards the iron core. This changes the magnetic field, which induces an alternating voltage in the coil, resulting in an alternating current. The shape of the wheel results in a sinusoidal oscillation. The gearwheel oscillator contains 91 tone wheels with different numbers of teeth, which are mounted on a common axle and driven by a synchronous motor via a transmission gear. As the sine tones produced in this way are not very musically appealing, several tones can be continuously assigned to each key of the manual via drawbars. The Hammond sound was supplemented by a mechanically generated reverb, a vibrato generated with rotary capacitors and electronic percussion. (source: music web.ch)