FM 03 and 04 are like the SinFM oscillators, but with gated "true FM' oscillators (the SinFM do not require gates).
FM 03 and 04 do not use the regular SDK modules to produce their FM carrier oscillator. Here, the Operator, which is usually a sine wave, can be any oscillator that you like, sine, pulse, or meta-osc.

• Osc Satellite section: allows you to load an oscillator satellite.
• The "In Mod" allows you to send the incoming modulation to the loaded satellite.
• Coarse and Fine allow you to detune the loaded satellite.
  
• Sat to FM: sets the volume of the Osc Satellite sent to modulate the FM Carrier.

• FM Carrier section:
  
• The coarse and fine are used to tune the Carrier.
  
• Echo Gate allows you to echo the gate signal to the osc satellite .

• Other Oscillators:
• The Sin FM oscillator includes a pulse oscillator tuned 1 octave below the Osc Satellite.
• Sub Level: sets the level of the sub oscillator.
• Detune: allows to detune the sub-oscillator. Detune is always relative to the Osc-Satellite tuning.
• +12 pitch (1 octave) can be applied with the LED switch.
  

• SRing to FM: amount of Sub+Ring sent to the FM Carrier, as a secondary source of modulation.

• Mix Section:
• You can set the levels of the Osc Sat, Sub+Ring and FM oscillator separately.
• By default, only the FM level is used, as other oscillators are used as modulators.

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