Orban OPTIMOD-FM 8600Si, Operating Manual

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OPTIMOD-FM DIGITAL INSTALLATION
2-29
6. Set response to an invalid or missing analog or digital input signal. (op-
tional)
Refer to step 3 on page 2-24
7. Defeat final clipper (optional).
If you are using the 8600Si to drive a network with protection audio processors
(like Orban’s Optimod-FM 5500) at each transmitter, you may wish to defeat the
8600Si’s final clipper to prevent double clipping, which will unnecessarily in-
crease distortion on-air. To do this:
A) Navigate to the Setup >
F
INAL
C
LIP . If
F
INAL
C
LIP does not appear, repeatedly
press the
Next
button until it does.
In PC Remote, this control is located in
I/O > U
TILITIES
.
B) Set
F
INAL
C
LIP
D
EFEAT to
D
EFEAT .
This will also defeat the overshoot compensator.
Note that defeating the final clipper and overshoot compensator will in-
crease peak output levels, possibly to the point where the 8600Si’s out-
put amplifier and/or digital output clips. It is wise to customize any pre-
sets you are using by reducing the
F
INAL
C
LIP
D
RIVE
and O
SHOOT
C
OMP
D
RIVE
controls to their minimum values. This will greatly reduce the
probability of inadvertently clipping the 8600Si’s output.
Unless defeated, the 8600Si’s composite limiter will continue to control
the composite output level. However, you should not use the composite
output when the 8600Si’s final clipper is defeated because this will re-
move the advantages of the distortion cancellation in the 8600Si’s final
clipper. (The composite limiter does not cancel distortion.)
This control does not work with MX presets, where final clipping is al-
ways active.
8. Set the polarity of the analog FM processing (optional).
In HD Radio installations, this command is useful when switching the 8600 be-
tween transmitters if the transmitters’ exciters produce opposite FM modulation
polarities when driven by identical digital audio input signals. This setting affects
any output emitting the analog FM processed signal, including the composite
output.
A) Navigate to the
I
NPUT
/
OUTPUT >
U
TILITES screen.
B) Set the
FM P
OLARITY control to
P
OSITIVE or
N
EGATIVE as appropriate for your
transmitter.
9. Configure Composite Outputs
A) Navigate to
Setup
> S
TEREO
E
NCODER
>
Next
> P
RE
-E
MPH . Set the pre-emphasis
to 50
µ
s or 75
µ
s, depending on your country’s standard.
B) Set
PILOT LVL
to
9%
.