Omnia Audio Omnia.ONE - Manual (Page 64)

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Stereo Generator
SCA Input Gain (Control On Rear Panel)
The SCA Input Gain control is an analog trimpot and does not appear in the menu. This trimpot is
located just above the SCA Input BNC jack on the rear panel. A small flat-blade screwdriver will
be needed to adjust it.
Signals input to the SCA jack are simply mixed into both composite outputs through the Gain
trimpot.
The gain range is from 0.034 (-29dB) to 1.35 (+2.6dB). At the lowest gain setting, you can feed it
a 10V SCA signal and get 8.6% injection on a 3.6V composite output setting. At the highest gain
setting, you can feed it a 0.25V SCA signal and get 8.6% injection on a 3.6V composite output
setting. (The composite + 9% pilot should be 3.6 Vp-p in these cases. The SCA adds to this,
making the total higher and the SCA 8.6% of the total).
There are five controls in the Stereo Generator menu and each will be explained in the order in
which they appear in the menu.
[Comp #1]
[Comp #2]
These composite MPX output level controls individually set the level at the two
separately buffered rear-panel composite outputs over a range of 0 to 10 volts in precise
0.05v increments. Rotate the jog-wheel to select the desired output, click and rotate to
adjust the modulation level for each composite output. Once the desired peak modulation
level is displayed, click the jog-wheel to set the level and return to the Stereo Generator
menu.
NOTE: Always use typical program material and a calibrated modulation monitor to
properly set modulation. To aid quick adjustment, it sometimes helps to advance the
Clipper Drive control before adjusting the composite outputs. Note that reference line-up
tones applied at the Omnia’s input cannot be used since the RMS level of a steady state
tone does not crest at 100% modulation.
[Pilot Lvl] (19 kHz Stereo Pilot Level)
Sets the pilot injection level from 4.0% to 12.0%, in 0.1% steps, relative to 100%
modulation. To defeat the pilot, simply adjust the Pilot Injection control below 4% and
the control indicates “Off”.
[Pilot Phs] (Pilot Phase)
This parameter sets the phase relationship between the 19 kHz pilot and the 38 kHz
suppressed carrier. The system default is 0.0º. The performance of the DSP based digital
stereo generator is theoretically perfect, however should the phase need adjustment in
order to offset time domain errors in the overall transmission system, the pilot phase can
be adjusted ±32º, in 1º increments.
We recommend that a calibrated modulation monitor be used for this adjustment.
[Separation]
The stereo “sound field” can be reduced by 3 dB or 6 dB to suppress processing-induced
multipath that can occur in certain terrain and within certain transmission systems when
heavy processing is used. When a setting of -3 dB or -6 dB is used, the amount of L-R
(perceived stereo effect) is also reduced. However in difficult RF signal coverage areas,
the amount of perceived multipath is reduced as well, resulting in the perception of a