Orban OPTIMOD-FM 8600Si, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL INTRODUCTION
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need to use the delay built into the HD Radio exciter and permitting the
8600Si’s internal stereo encoder and composite limiter to drive the ana-
log FM exciter
. Each output (Analog, Digital 1, Digital 2, Composite) can be in-
dependently configured to emit the delayed or undelayed signal .
•
The analog inputs are transformerless, balanced 10k
Ω
instrumentation-
amplifier circuits . The analog outputs are transformerless balanced and float-
ing (with 50
Ω
impedance) to ensure highest transparency and accurate pulse re-
sponse.
•
The 8600Si has two independent composite baseband outputs with digi-
tally programmable output levels. Robust line drivers enable them to drive 100
feet of RG-59 coaxial cable without audible performance degradation.
•
The 8600Si’s two subcarrier inputs are mixed with the output of the 8600Si’s
stereo encoder before application to the composite output connectors. One in-
put can be re-jumpered to provide a 19 kHz pilot reference output. Both inputs
have internal level trims to accommodate subcarrier generators with output lev-
els as low as 220 mV.
•
The 8600Si precisely controls the audio bandwidth of its analog FM proc-
essing to 16.5 kHz. This prevents significant overshoots in uncompressed digital
links operating at a 44.1 kHz-sample rate or higher and prevents interference to
the pilot tone and RDS (or RBDS) subcarrier. The bandwidth of the 8600Si’s
digi-
tal radio output is adjustable in 1 kHz increments between 15 kHz and 20 kHz.
•
The 8600Si has a defeatable multiplex power limiter that controls the multi-
plex power to ITU-R BS412 standards. An adjustable threshold allows a station to
achieve maximum legal multiplex power even if the downstream transmission
system introduces peak overshoots into the 8600Si-processed signal. Because this
limiter closes a feedback loop around the audio processing, it allows the user to
adjust the processor’s subjective setup controls freely without violating
BS412 limits, regardless of program material. The multiplex power limiter acts on
all outputs (not just the composite output). In its most common configuration, it
reduces clipper drive when it reduces power, simultaneously
reducing clipping
distortion . However, to accommodate customers who wish to use heavier
clipping to achieve a certain sound , the MPX power controller can be con-
figured to reduce gain after the clippers.
•
All input, output, and power connections are rigorously RFI-suppressed to
Orban’s traditional exacting standards, ensuring trouble-free installation.
•
The 8600Si is designed and certified to meet all applicable international
safety and emissions standards .