Motorola BT100 - Manual (Page 23)

2-12 Overview
BT100 Installation and Operation Manual
Ingress Control Switch
The ingress control switches (ICS) provide return-path signal attenuation or cutoff in the
BT100. An ICS is required for each output port. Therefore the standard four output BT100
requires four ICS’s. Switching is accomplished through the frequency agile LIFELINE
status-monitoring transponder, which you can purchase directly from AM Networks.
Figure 2-12 illustrates the LL-BTA-HMS and the required cable connections to the electronics
chassis.
Figure 2-12
LL-BTA-HMS status monitor
The ICS provides a means of isolating sources of ingress from a centralized location. Using a
downstream command through the LIFELINE status-monitoring system, you can attenuate the
return path through the amplifier by 6 dB or by 38 dB. By reducing the ingress level at the
headend or monitoring point, you can further isolate the ingress source. After you isolate an
ingress source to the last possible amplifier, node, or line extender, you can shut the return path
off at that location. This limits the impact of the ingress on the remainder of the network while
eliminating the source of ingress.