Chippmann Omega-PhiCS-8 Series, Руководство пользователя

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CS-8 Series Omega-Phi Rev1.04, Oct. 2015
-27-
PM result
(Index=2)
Sinus
(VCO-Kern)
Sinus
(Modulator)
PM result
(Index=12)
Fig. 7b PM with doubled index by frequency doubling (modulator)
One can say, that the phase modulation is a "harder" modulation than FM,
since one cannot generate stepping waves due to modulation; an infinite
short and infinite high voltage pulse would be needed to generate a definite
jump in a sine carrier. With the PM it becomes easy. Take a step function as the
modulator and the phase jumps.
Because it is the phase
change which could be heard, with low-frequency saw-
tooth waves, e.g., which amplitude is adjusted to shift the phase by exactly
360° or 720°, constant detunes can be generated. E.g. with a rising saw-tooth
of 1 Hz, which shifts the phase repetitive by 360°, detunes the output
frequency by 1 Hz, with 720° phase shift by 2 Hz. Superposition with VCO core
output (Omega) one obtain a fat beat as y ou would have two detuned
oscillators.
8.6.1. The PM VCA
Fig. 3b above shows that the control input of the Phase-shifter is fed by a value
of the
Phi -controller on the one hand and by an output of a VCA on the other
hand. the modulation signal will be applied at the