78
feed
it a 0.25V SCA signal and get 8.6% injection on a 3.6V composite output setting. (The com
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 fr
om 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 are
as, the amount of perceived multipath is
reduced as well, resulting in the perception of a much cleaner overall signal with better penetration
and coverage. The Omnia ONE
FM defaults to a setting of
Stereo
, using the full L-R signal. We
suggest that you leave it in that mode, but the other settings are available for those who wish to
experiment, including a setting of full
Mono.
<Exit
Click on this option to return to the
Input/Output
menu.
Bypass
[Process]
This is the normal default setting where all processing will be active.
[Bypass]
This setting will bypass all processing for test purposes.
