User's Manual

Internal Assembly Identification and Location68P09255A69-3
Aug 2002
1X SC4812ET Lite BTS Optimization/ATP Software Release 2.16.1.x
PRELIMINARY
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Battery Heaters
The battery heater pads warm the batteries to provide improved
cold-weather performance. A separate heater pad is required for each
battery string and is located between each battery string and its
respective support shelf.
Channel Service Units (CSU) (Optional)
The SC4812ET Lite can be equipped with up to two M-PATH 537 CSU
modules for T1 spans or two M-PATH 437 CSU modules for E1 spans.
These modules install in the CSU shelf (Figure 1-3). The CSUs allow
monitoring of span performance and provide capability for remote
network management.
CSU Shelf
The CSU shelf is an ADC Kentrox 2-slot Universal Shelf which can
accommodate two M-PATH 537 or two M-PATH 437 CSU modules.
When the optional CSU modules are not installed, cover plates are
installed over the CSU card slots (Figure 1-3).
DC Power Distribution Assembly (PDA)
Both rectifier output voltage and back-up battery voltage are routed to
the PDA (Figure 1-3) where they are combined into system DC bus
voltage. The PDA provides distribution of DC power and system DC
bus protection from the loads with MAIN BREAKER and the smaller
post-distribution circuit breakers. MAIN BREAKER permits removal of
all frame loading from the bus. The 13 post-distribution circuit breakers
permit removal of individual loads.
Duplexer, Receive filter, Dual Directional Coupler
(DRDC)
DRDCs permit duplexing of sector transmit and receive signals on a
single antenna. The DRDCs also incorporate a receive bandpass filter
and dual directional couplers which permit signal monitoring by the RF
Diagnostic Subsystem.
ET Interface Board (ETIB) and LPA Control (LPAC)
Board
The ETIB is an interconnect module with status LEDs, MMI receptacles,
and secondary surge protection for the LPA modules. The LPAC board
provides the interface for the LPA connections (Figure 1-3).
Filter/Combiner Shelf (Bandpass Filters or 2:1
Combiners)
The filter/combiner shelf (Figure 1-3) holds the transmit bandpass filters
or 2:1 combiners, depending on system configuration.
Heat Exchanger
The heat exchanger provides cooling to the frame RF compartment. The
fan speed of the heat exchanger adjusts automatically with temperature.
The heat exchanger is located in the frame main door (Figure 1-2).
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