Forward path alignment, Before you begin – Motorola BLE100 User Manual
Page 23
3-2
Amplifier Setup
BLE100 Installation and Operation Manual
To successfully setup the BLE100, you need to perform the following tasks:
Forward path alignment
Return path alignment
Check powering and surge protection options
Forward Path Alignment
You must perform the following BLE100 alignment procedures for proper performance in the
forward path:
Select the appropriate cable equalizer or cable simulator
Select the appropriate input and midstage pads
Verify proper flatness control
Verify proper level control
Before You Begin
Before you begin to set-up the amplifier and perform forward-path alignment, please read the
following instructions and recommendations.
For proper forward alignment obtain:
RF output levels and tilts of all BLE100s in the forward or return path
RF input level for the BLE100 being set up (from system design or as-built map)
A carrier at the system’s highest frequency. It can be modulated or continuous wave (CW)
and should be inserted in the headend at standard video levels. This carrier is used to
simplify field set-up.
It is recommended that you:
Install the system design value SFE-100-* and a high value (20 dB or above) input pad
(
JXP
IN
) before you install or remove the electronics chassis or apply power to the BLE100.
Leave the
JXP IN
pad location open if a high value pad is not available. A more accurate
forward input test point reading is achieved with a high value pad installed.
Do not remove the electronics chassis cover while the BLE100 is powered.
Do not use wire jumpers to bypass the SFE-100-* location.
Recognize that actual pad and SFE-100-* values may differ slightly from their design
values. This is caused by factors such as walkout errors, worst-case data utilization during
design and temperature variation from 70
°F.
Secure the electronics chassis in the housing base and torque to 18-22 in-lbs. to facilitate
heat transfer and avoid damage from overheating.
If the electronics chassis cover was removed for any reason, shut off the AC power
before you reinstall the cover. Verify that all chassis cover screws are tightened to
10–12 in-lbs.
Perform a bench alignment. Pre-aligning the BLE100 response on the bench (Section 4,
“Bench Testing”) for a system signature simplifies field alignment.