Motorola BLE100 - Manual (Page 33)

3-12 Amplifier Setup
BLE100 Installation and Operation Manual
5 Turn the auto level control potentiometer (ADU) (illustrated in Figure 2-8) fully clockwise
and then reduce to obtain the level obtained in Step 9 under Manual Gain Control.
ADU/QADU Pads and Levels
This subsection provides information regarding the proper ADU/QADU padding requirements
for the BLE100.
A JXP-*B pad is installed in the input line to the ADU/QADU location. This pad adjusts the
ADU/QADU input level for the standard application of the BLE100. You can change this pad
depending on the operational output of the BLE100.
In the BLE100 analog ADU circuit, a JXP-7B pad is generally recommended. This is the
standard ADU pad value as shipped from the factory and is appropriate for an amplifier output
level range from
+43 dBmV to +49 dBmV at 550 MHz. Use a JXP-1B pad for output levels below
+43 dBmV and a JXP-11B for output levels above +49 dBmV.
The standard pad for the QADU is a JXP-0B. This pad value works for a BLE100 output level
from
+38 dBmV to +47 dBmV at 550 MHz. Use a JXP-7B when operating above +47 dBmV at
550 MHz.
Motorola does not recommend operating the BLE100 above
+46 dBmV at 550 MHz.
Use of an ADU or QADU is recommended for improved output level stability although you can
operate the BLE100 in the manual mode. Select manual mode by placing the drive control select
jumper, illustrated in Figure 2-8, in the
MAN position. The gain of the BLE100 is then
determined by the potentiometer marked MAN on the amplifier cover.
Return Path Alignment
The following subsections describe the BLE100 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:
ƒ RF alignment levels and insertion points for all BLE100s
ƒ RF reference output level of the headend optical receivers
Equipment required for return-path alignment includes:
ƒ Full complement of JXP-*B pads and Starline Return Equalizers (SRE-*-*)
ƒ Reverse signal generator — must produce at least one signal within the return bandpass
and have variable output
ƒ Return sweep or alignment equipment
It is recommended that you:
ƒ Do not remove the electronics chassis cover when the BLE100 is powered
ƒ Do not use wire jumpers to bypass the SRE-*-* location