Service Manual

GSM-204-323
Compact transceiver unit (CTU)
31st Oct 01
Technical Description: Horizon macro outdoor
68P02902W02-A
CONTROLLED INTRODUCTION
Tech. 5–11
CTU connectors
and reset
The TTY RS-232 serial port has three serial links onto the 9-way connector:
 Radio subsystem (RSS).
 Equalizer and control processor (EQCP).
 Channel coder control processor (CCCP).
A test interface port on the CTU front panel provides access to critical test
points for factory alignment and maintenance.
Pressing the reset push button generates a hard reset of the processor,
initiating a normal power-up. Later versions of the CTU (mid 2001 onward), have
no reset button, reset is acheived by operation of the appproriate CTU circuit
breaker on the CBM.
Figure 5-3 shows the front panel and Table 5-2 shows connector functions.
.
Tx OUT CONNECTOR
TTY INTERFACE
TEST INTERFACE
Tx STATUS LED
RADIO STATUS LED
RECESSED MANUAL
RESET BUTTON (if fitted)
Figure 5-3 CTU front panel showing connectors and reset button
Table 5-2 CTU front panel connectors
Front panel legend Function Connection to
TRANSMIT OUT Transmitter RF output Tx Block
TTY INTERFACE Test access to processor Three RS-232s
TEST INTERFACE Factory use Test equipment