Orban OPTIMOD-FM 8600, Operating Manual

Page: 71 / 397

OPTIMOD-FM DIGITAL INSTALLATION
2-11
drawing on page 6-37. The schematic diagram showing J400 is on page 6-
56.
Connect your subcarrier generator(s) to the 8600’s subcarrier input(s)
with coaxial cable terminated with BNC connectors.
The subcarrier inputs have greater than 600 Ω load impedance and are
unbalanced. Their sensitivity is variable from 220 mV p-p to > 10 V p-p to
produce 10% injection via trimmers that are accessible for screwdriver
adjustment through holes in the rear panel.
Using the
P
ILOT
R
EFERENCE
control (in the
I
NPUT
/O
UTPUT
> C
OMPOSITE
screen), you can set the phase of the reference to 0 ° , 90 ° , 180 ° , or 270 °
with respect to the pilot tone appearing at the composite output.
You can use the
19K R
EF
control in
S
ETUP
to determine whether the 19 kHz pilot
reference output will be in-phase (
0 DEG
) with the pilot tone present in the compo-
site output or will lead it by 90 degrees (
90 DEG
).
0 DEG
is correct for most installa-
tions. Use
90 DEG
only if your RDS/RBDS generator’s 19 kHz reference input specifi-
cally requires this phase relationship.
Digital Composite Outputs
In MPX hardware, there is also an AES3 digital composite output at 192 kHz sample
rate. Its output level is set in the Input/Output 5 screen titled Composite 2. At the PC
remote, it is located in the
I/O S
ETUP
S
CREEN
with the tab
D
IGITAL
E
NCODER
.
This output appears on a male XLR-type connector on the breakout cable supplied
with your Optimod. This output is fully compatible with and interoperable with the
de-facto industry standard digital connection being implemented by transmitter
manufacturers and others.
Digitized Subcarrier Inputs
In MPX hardware, two additional subcarrier inputs are provided on the breakout
cable. These are digitized and are summed only into the digital composite output.
Their mix level is set in the Input/Output 5 screen titled Composite 2. At the PC re-
mote, they are located in the
I/O S
ETUP
S
CREEN
with the tab
D
IGITAL
E
NCODER
.
If you need to use both the digital and analog composite outputs, you must split the
outputs of your SCA generators with Y cables so that each generator output drives
one digitized SCA input and one non-digitized SCA input.
Wordclock/10 MHz Sync Reference Input
The sync reference input (labeled
R
EF
I
N
) appears on a female BNC jack at the end of
the breakout cable that connects to the digital composite connector. It is available
only on MPX hardware. It accepts a 1x 5V p-p squarewave wordclock signal at 32,
44.1, 48, 88.2, or 96 kHz, or a 10 MHz sinewave or squarewave signal, 0.5 to 5 V
peak. 10 MHz is a common output frequency produced by GPS and rubidium fre-
quency standards. You can configure the 8600 to lock its 19 kHz pilot tone and out-
put sample frequency to this input.