Motorola BLE100 - Manual (Page 34)

Amplifier Setup 3-13
BLE100 Installation and Operation Manual
ƒ Perform the return optical link set up before performing amplifier set up
ƒ Specify reverse alignment design levels for a single carrier
ƒ Consider sweep equipment as a single carrier and operate at design levels
ƒ Do not include injection point losses in reverse design levels
If JXP THERM devices (JXP-TH*C) are specified for level control, they should be installed in
the JXP THERM pad facility (illustrated in Figure 2-8).
Alignment Procedure
The return amplifier configuration includes one high-gain (30 dB) return amplifier hybrid, and
an appropriate SRE-*-* equalizer. All components are plug-in and are easily installed.
To align the return path:
1 If the BLE100 is powered, remove all fuses before you perform the following steps.
2 Install the design value pad in the return output pad location ( JXP OUT ).
3 Install the design value return equalizer, SRE-*-*, in the RTN EQ location.
4 Verify that the return input pad location ( JXP - IN ) has a 0 dB pad (or JXP-ZX jumper)
installed.
5 If you require an ICS, install it in the ICS location. If you plan to install the ICS later,
install a JXP-2B to simulate the through-loss of the ICS. This eliminates the need to
rebalance the return path if you install the ICS later.
6 Verify that the return output pad socket ( JXP OUT ), located between the hybrid output and
the SRE-*-*, has a 0 dB pad (or JXP-ZX jumper) installed.
7 Verify that the return thermal pad socket ( JXP THERM ), located between the hybrid output
and the SRE-*-*, has a 0 dB pad (or JXP-ZX jumper) or JXP-TH*C installed.
8 Set the sweep equipment output level to the amplifier’s design input level. Add insertion
point loss.
9 If required, change the return output pad ( JXP OUT ) and/or return equalizer to achieve, as
close as possible, a match of the reference level as compared to the node.
10 Verify the sweep response of all insertion points if applicable.
11 Verify that the pad and equalizer values are similar to the map design values.
You can verify proper return alignment by injecting a carrier, at the design level, into any
amplifier at random. Proper alignment is achieved if you observe the reference level at the
headend optical receiver output.