Location of Master Oscillator Components
on a Vox 304 Jaguar Tone Generator Card
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Location of Master Oscillator Components
on a Vox 304E Jaguar Tone Generator Card
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The Vox Jaguar organ utilizes twelve printed circuit "tone generator" cards to produce four octaves of notes in the chromatic scale. These generator cards are mounted side by side inside the organ, as shown here.
Although the tone generator cards for the V304 Jaguar (produced for Vox in Italy by GEM) and V304E Jaguar (produced for Vox in Italy by EME) have a different component layout, the circuitry of these tone generator cards is essentially identical.
Each tone generator card includes a "master oscillator" circuit which creates the twelve notes in the highest octave of the organ and a three stage "frequency divider network." The first stage of the divider network drops the pitch of tones coming from the master oscillator circuit by one octave. The pitch from the first divider network is then directed to the second divider network dropping the pitch a second octave. Finally, the pitch from the second divider network is directed to the third divider, dropping the pitch yet another octave and completing the generation of four octaves of notes for the Jaguar organ.
The master oscillator circuit combines a variable inductor (L1 in the illustrations at left), two capacitors (C1 and C2), one transistor (Q1) and three resistors (R1, R2 & R3) to create what is known as an variable "LC circuit." The LC circuit creates an organ tone whose pitch is |
