M0041AMB.doc
ID No 7164468
Page 7
12. Attenuation
Setting
The attenuation of the miniRepeater can be set by
means of a rotary switch. There is a label on the
miniRepeater that shows the possible positions of the
rotary switch and the corresponding values of the
attenuation. The attenuation can be set, using a small
screwdriver, in the range from 0 dB to 20 dB in steps
of 2 dB or “auto setup” may be selected.
When auto setup is selected, the miniRepeater will
automatically set its gain to maximize RF
performance. The downlink gain will be automatically
set to operate the repeater at its maximum output
power, while not exceeding the ALC limit. The uplink
gain will be set to the value of the downlink path.
If the level of the BTS signal increases, the
miniRepeater will decrease the gain in the downlink
and uplink paths automatically. However, the
miniRepeater will increase the gain again in timely
intervals of 24 hours if the level of the BTS signal
decreases.
Rotary switch for attenuation setting
13.
Alarming and Supervision
13.1.
Functional Description of the Alarming-
Interface
For alarming and supervision, the miniRepeater is
provided with an alarming interface represented by
two LEDs and output contacts:
LEDs and output contacts
LED1:
This three-colour LED provides visual
equipment status information:
off
no power feed
green
normal operation condition
orange
hardware alarm (out of defined power-
window) or LO (Local Oscillator) does
not lock
red
temperature of repeater too high
LED2:
This one-colour LED provides visual
information about the ALC-status (Automatic
Level Control):
off
normal operation condition
red
ALC-Alarm, ALC active
13.2. Output-Contact
Configuration
a3 GND
Output1
(TTL level)
b3 Heartbeat
b1
Hardware-
Alarm – C
Output2
(Optocoupler
output)
b2
Hardware-
Alarm – E
a1 ALC-Alarm – C
Output3
(Optocoupler
output)
a2 ALC-Alarm – E
Output-contact configuration
LED 1
LED 2
