Chippmann Omega-PhiCS-8 Series, Руководство пользователя

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CS-8 Series Omega-Phi Rev1.04, Oct. 2015
-28-
PM -jack: It channels the input unabated to an VCA-input. These input voltages
shouldn't exceed 10 V, if linear working of the VCA is wished, best is 5 V.
Index/Depth - controller: The
Depth
-controller attenuates the modulation
signal at jack 9 (Envelope symbol) between 0 and 1. This signal will be added
to the value of the
Index
-controller. In case that nothing is applied at
Depth
or
it's in full CCW position in the first instance
Index
, turning from the middle
position (no effect) to full CW, the modulation depth will increase. Turning it to
the left up to full CCW, nothing more will happen. At
Depth positive as
negative voltages could be applied, which either increases or decreases the
index value. By turning the
Index
-controller to the left high (positive)
modulation voltages at the
Depth
-controller can be cut.
A capacitive decoupling is not necessary, because offsets only leading to a
constant phasing, what could be corrected with the
Phi
-controller. But, as
mentioned above, the polarity could be of interest and therefore there is the
Polarity -switch: This switch inverts or not the modulation signal at the PM-
input, inverting in position "180°", non-inverting in position "0°".
9. THEORETICAL PRINCIPLES
To understand the mathematics behind these modulating operations, specific
knowledge are absolute requirements. So, this short chapter turns to complete
experts, but shouldn't be unmentioned for the sake of completeness.
9.1. Frequency modulation FM
In general terms the frequency modulation with a sinus function as a carrier
could be written as follow
ൌ ∙ ࣓ ∙ ࣓ ∙
࢚
FM(t) is the modulation result, A
0
its amplitude,
ω
0
is the basic angular
frequency of the oscillator (that is 2
π
f
0
, with f
0
the oscillator frequency) given