Rfds Modules; Rfds Preselector (700/800 Mhz); Rfds Preselector (Uhf); Figure 16: Preselector Filter (700/800 Mhz) - Motorola ASTRO 25 GTR 8000 Manual

MN003286A01-E
Chapter 2: GTR 8000 Base Radio Theory of Operation
2.3

RFDS Modules

The Radio Frequency Distribution System (RFDS) equipment included in your system depends on
which options were purchased from Motorola Solutions. The following are some examples of the RFDS
equipment available for your system.
NOTICE: If the RTTE option was selected, a duplexer is required for applicable applications.
2.3.1

RFDS Preselector (700/800 MHz)

The preselector provides a first level of band pass filtering for inbound RF signals. RF input and output
connectors are cabled to the RF Output RX-A. This filter must be included to fulfill TIA102-CAAB Class
A spurious response rejection (90 dB). The filter is not required when using a receiver multicoupler
system. This filter CANNOT be retuned in the field.

Figure 16: Preselector Filter (700/800 MHz)

2.3.2

RFDS Preselector (UHF)

The preselector rejects unwanted signals including the transmitter signals from overloading the
receiver. This filter must be included to fulfill TIA102-CAAB Class A spurious response rejection (90
dB). The filter is not required when using a receiver multicoupler system. This filter can be retuned in
the field.
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