Motorola BT100 operation manual Alignment Procedure

Amplifier Setup 3-13

ƒReverse signal generator — must produce at least one signal within the return bandpass and have variable output

ƒReturn sweep or alignment equipment

It is recommended that you:

ƒDo not remove or install the electronics chassis cover when the BT100 is powered

ƒDo not use wire jumpers to bypass the SRE-100-* location

ƒPerform the return optical link set up before performing amplifier set up

ƒSpecify reverse alignment design levels for a single carrier

ƒConsider sweep equipment as a single carrier and operate at design levels

ƒDo 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 2-13) prior to alignment.

Alignment Procedure

The return amplifier configuration includes one high-gain (30 dB) return amplifier hybrid, and an appropriate SRE-100-* equalizer. All components are plug-in and are easily installed.

To align the return path:

1If the BT100 is powered, remove all fuses before you perform the following steps.

2Install the design value pad in the return output pad location (JXP) which is located directly beneath the JXP THERM.

3Install the design value return equalizer, SRE-100-*, in the location “RTN EQ”.

4Verify that the return input pad locations (JXP, JXP 1, JXP 3, and JXP 4) have 0 dB pads (or JXP-ZX jumpers) installed.

5If you require ICSs, install them in the ICS locations illustrated in Figure 2-13. If you plan to install the ICSs later, install JXP-2Bs to simulate the through-loss of the ICSs. This eliminates the need to rebalance the return path if you install the ICS later.

6Verify that the return pad (JXP location located to the right of the return hybrid) has a 0 dB pad (or JXP-ZX jumper) installed.

7Verify that the return thermal pad socket (JXP THERM), located between the hybrid output and the SRE-100-*, has a 0 dB pad (or JXP-ZX jumper) or a JXP-TH*C installed.

8Set the sweep equipment output level to the amplifier’s design input level. Add insertion point loss.

9If required, change the return output pad and/or equalizer to achieve, as close as possible, a match of the reference level as compared to the node.

10Verify the sweep response of all insertion points, if applicable.

11Verify that the pad and equalizer values are similar to the map design values.

For systems that must meet especially stringent return-path flatness requirements, you may need additional flatness response correction in the return path. You can obtain additional flatness by installing the JXP-RPC board in one of the return-path JXP pad facilities. The recommended location is the JXP-THERM pad facility. However, if you are using JXP-THERMS in the return

BT100 Installation and Operation Manual