Figure 5-29 Mcb Board - Motorola Starline SG 2000 Installation And Operation Manual

5 - 2 8 O p e r a t i o n
Description
Alarm test point
3 dB test point
Potentiometers ICS1
through ICS4
Figure 5-29 illustrates the MCB board, switches, potentiometers, and test points:
F i g u r e 5- 29
M CB boa rd
S2
S1
S G 2 0 0 0 I n s t a l l a t i o n a n d O p e r a t i o n M a n u a l
Function
( ) provides access for measuring the cross-over optical level
ALRM TP
threshold.
(3 dB ) is used to measure the optical power of the primary receiver.
TP
Measurements at this test point are 3 dB less than the actual value.
Control the attenuation of the ingress control switches (ICS) when they are
installed in the return paths of the RF output ports. The factory setting is for
minimum attenuation, however, they can be set for a maximum attenuation
of approximately 40 dB. The following list indicates the potentiometer and
its corresponding housing port:
housing port
ICS1 IN
housing port
ICS2 OUT
housing port 1
ICS3
housing port 3
ICS4
ICS4 ICS2 ALRM
ICS3 ICS1
RF chassis port 1
RF chassis port 2
RF chassis port 3
RF chassis port 4
3 dB TP
ALRM TP