Crown FM250G, Руководство пользователя

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Rev A
Getting Acquainted 1—5
1.2.5 Translator
The FM30GR receiver option replaces the audio processor and stereo generator
boards with a receiver module. This added feature makes Crown transmitters ideal
for translator service in terrestrial-fed networks. These networks represent a
popular and effective way to increase your broadcasting coverage. Translators,
acting as repeater emitters, are necessary links in this chain of events.
Traditionally, network engineers have relied on multiple steps and multiple pieces of
equipment to accomplish the task. Others have integrated the translator function
(receiver and exciter) to feed an amplifier. Crown, on the other hand, starts with an
integrated transmitter and adds a solid-state Receiver Module to form the ideal
translator.
This option enables RF in and RF out on any of Crown’s FM series of transmitters.
In addition, the module supplies a composite output to the RF exciter portion of the
transmitter. From here, the signal is brought to full power by the built-in power
amplifier for retransmission. The Receiver Module has been specifically designed to
handle SCA channel output up to 100 kHz for audio and high-speed data.
FSK ID programming is built-in to ensure compliance with regulations regarding
the on-air identification of translators. Simply specify the call sign of the repeater
station when ordering. Should you need to change the location of the translator,
replacement FSK chips are available. The Receiver Module option should be ordered
at the time of initial transmitter purchase. However, an option kit is available for
field converting existing Crown units.
In the translator configuration there are differences in the function of the front
panel, See Section 3.7, Digital Multimeter for a description.
Illustration 1–3 Crown’s Integrated Translator
RF Exciter
Receiver
Module
(Option)
RF In
Low-Pass
Filter
RF Out
Metering