Motorola BLE100 - Manual (Page 19)

2-8 Overview
BLE100 Installation and Operation Manual
The input and output of the return path each include a JXP-*B pad facility. You can also use
either pad socket as a test point or a signal injection point. The return output pad value is
normally selected to control the return signal level into the next upstream amplifier. Select an
appropriate return input pad to attenuate excessive input signal.
The return-input test point and the return-output test point are
−20 dB directional couplers.
Both test points present 75-ohm source impedance and do not require special test probes.
Ingress Control Switch
The ingress control switch (ICS) provides return-path signal attenuation or cutoff in the
BLE100. This is accomplished through the frequency agile LIFELINE
® status-monitoring
module, which you can purchase directly from AM Networks. (Figure 2-8 illustrates the location
of the optional ICS).
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 line extender 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 an ingress source is isolated 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.
Options and Accessories
The factory ships the BLE100 as a fully functional unit, but you must configure it appropriately
for the field-location requirements. You must install the correct forward equalizer or broadband
cable simulator and input pad to place the unit into service. Section 3, “Amplifier Setup”
provides information to assist you in this task. Use model JXP-*B pads to control field signal
levels. To compensate for temperature, install the automatic drive unit (ADU) or QAM
automatic drive unit (QADU) before placing the BLE100 in service. You can install other items,
such as return thermal attenuators or ingress control switches at your discretion, but these
options do not render the BLE100 inoperative if they are not included.
Table 2-1 provides a comprehensive list of options and accessories for the BLE100. See
Section 3, “Amplifier Setup,” or the Motorola online product catalog for additional information.
Table 2-1
BLE100 options and accessories
Model Description Function
QADU-* QAM Automatic Drive Unit This board automatically controls amplifier output levels
that change with cable attenuation and hybrid output.
The selection of an appropriate pilot frequency is
required.
ADU-* Automatic Drive Unit This board automatically controls amplifier output levels
that change with cable attenuation and hybrid output.
The selection of an appropriate pilot frequency is
required.