Adu Pads And Levels; Return Path Alignment; Before You Begin; Table 3-4 Ble*/* Agc Pad Levels - Motorola BLE Series Installation And Operation Manual

3-12 Amplifier Setup

ADU Pads and Levels

This subsection provides information regarding the proper ADU padding requirements for the
BLE*/*.
A JXP-*B pad is installed in the input line to the ADU location. This pad adjusts the ADU input
level for the standard application of the BLE*/*. You can change this pad depending on the
operational output of the BLE*/*.
In general, a JXP-6B pad is recommended in the BLE*/* ADU circuit or a JXP-0B for the QAM
ADU. These are the standard ADU pad values as shipped from the factory and are appropriate
for an amplifier output level range from +43 dBmV to +49 dBmV at 550 MHz. For the QAM
ADU, the 0 dB pad works up to +47 dBmV at 550 MHz.
To determine the correct ADU pad value for other output levels, refer to Table 3-4:
Table 3-4
BLE*/* AGC pad levels
Option Pad Value
(below +43 dBmV)
ADU 0 dB
QADU 0 dB
The use of the ADU or TDU is recommended for improved output level stability although you
can operate the BLE*/* in the manual mode. Select manual mode by placing the drive control
select jumper, illustrated in Figure 2-8, in the
determined by the potentiometer marked

Return Path Alignment

The following subsections describe the BLE*/* alignment procedures required for proper
performance in the return path.

Before You Begin

Before you begin to set-up the amplifier and perform return-path alignment, please read the
following instructions and recommendations.
For proper return alignment obtain:
RF alignment levels and insertion points for all BLE*/*s
RF reference output level of the headend optical receivers
Equipment required for return-path alignment includes:
Full complement of JXP-*B pads and Starline Return Equalizers (SRE-*-*)
Reverse signal generator — must produce at least one signal within the return bandpass
and have variable output
Return sweep or alignment equipment
BLE*/* Installation and Operation Manual
Pad Value
(above +47 dBmV)
N/A
6 dB
position. The gain of the BLE*/* is then
MAN
on the amplifier cover.
MAN
Pad Value
(above +49 dBmV)
10 dB
N/A