Operating instructions

Amplifier Setup 3

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BLE*/* Installation and Operation Manual

Equipment required for return-path alignment includes:

! Full complement of JXP-*T 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

It is recommended that you:

! Do not use wire jumpers to bypass the SRE-*-* location

! Perform the return optical link set up before performing amplifier set up

! Specify reverse alignment design levels for a single carrier

! Consider sweep equipment as a single carrier and operate at design levels

! Do not include injection point losses in reverse design levels

If JXP THERM devices (JXP-TH*T) are specified for level control, they should be installed in

the JXP THERM pad facility (illustrated in Figure 2-9) after alignment has been performed.

Alignment Procedure

The return amplifier configuration includes one low-gain (25 dB) or 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 BLE*/* is powered, remove all fuses before you perform the following steps.

2 Carefully install a reverse hybrid amplifier, if necessary, and install the design value pad

and equalizer in the output locations.

3 Ensure that both hybrid screws are tight. Torque the screws to 10 to 12 in-lbs. Over torque

can damage the hybrid.

4 Verify that there is a 0 dB pad (JXP-ZXT jumper) installed in the return input pad location

(JXP-IN).

If the optional ICS was ordered, verify that it is in the ICS location. If it was not ordered,

the factory installed jumper should remain in the ICS location.

5 Verify that the output pad closest to the hybrid output (JXP-OUT) has a 0 dB pad

(JXP-ZXT jumper) installed.

6 Verify that the output pad socket (JXP THERM), located between the hybrid output and the

SRE-*-*, has a 0 dB pad (JXP-ZXT jumper) or a JXP-TH*T installed.

7 Set the sweep equipment output level to the amplifiers design input level. Add insertion

point loss.

8 If required, change the output pad and/or equalizer to achieve, as close as possible, a match

of the reference level as compared to the node.

9 Verify the sweep response of all insertion points if applicable.

10 Verify that the pad and equalizer values are similar to the map design values.