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888-2587-001
4/18/11
WARNING: Disconnect primary power prior to servicing.
FM HD Radio System
Section 1 Introduction/Specifications
The main input is the AES3 audio (32 kHz to 96 kHz) signal for the MPS (main
program service) HD digital program. The Exporter also has an AES3 (32kHz to 96kHz
input and corresponding output for the main FM channel (analog) with a fully
adjustable diversity delay. Another input is the MPS PAD data. Secondary input from
the HDI-100 Importer is
only
for supplemental program services (SPS). The outputs of
the Exporter are the delayed main channel AES audio and an HD stream of up to 300
kbps (currently this is about 128 kbps) unidirectional UDP Ethernet for the digital
carriers.
1.2.3
HDI-100 Importer
The FlexStar™ HDI-100 Importer is required for any Supplemental Program Services
(SPS). It accepts, manages, encodes and multiplexes all Advanced Application Services
(AAS) including supplemental audio channels and program associated data (PAD) for
transport to the HDE-100 Exporter or to an existing DEXSTAR Exciter. It also manages
system bandwidth allocation.
The Importer is a
dedicated server
running several programs for this purpose. Do not
use the Importer for other functions as data collisions resulting in audio drop-outs will
result. The Importer will manage the bandwidth allocated for each of the inputs for the
digital carriers. The Importer must be co-located with the Exporter. You will need a
keyboard, monitor and mouse to set up the software applications. The platform is
typically a Pentium 4 PC with windows XP operating system. The Importer works best
when not subject to automatic updates or a continuous connection to the public Internet.
The inputs are AES audio for each SPS channel to be configured. The Importer output
is an Ethernet connection to an Ethernet switch.
1.2.4
STL (Studio Transmitter Link)
The STL is a major component of the system. Its purpose is to transport all audio and
data from the studio to the remote transmitter site. Typically the STL will have
equipment on each end of a link, and the link can be a 900MHz/950MHz RF path
microwave hop, telecom, satellite, direct fiber, etc. Uni-directional systems are
sufficient however bi-directional STL’s are becoming more common.
Whatever system you select, it must have the dual throughput capability of audio and
2nd signal of UDP data at a 300kbps rate (current configurations requite a minimum
128kbps) Ethernet. Future systems will require 300kbps to accommodate additional
services later on without the need to allocate more STL bandwidth. Since the HDx-FM
Exciter audio inputs are configurable you may use AES3, composite or descrete L/R for
the FM ("analog") source.
