Motorola BT100 - Manual (Page 26)

BT100 Installation and Operation Manual
Section 3
Amplifier Setup
This section provides instructions on how to properly handle and configure the BT100. It also
describes the proper forward and return path alignment procedures. It is recommended that you
read this entire section before you install the BT100.
Proper Handling Procedures
The following information is useful in reducing GaAs RF amplifier failures caused by
Electrostatic Discharge (ESD) or Electrical Over Stress (EOS).
Many electronic components are vulnerable to ESD and EOS. Improper handling during service
and installation can subject the BT100 to performance degradation or failure. All closed
operational units are equally protected. Compliance with proper handling procedures can
significantly reduce ESD and EOS related failures.
To avoid excessive signal level which causes EOS, follow the procedures listed below:
Field Practice
Proper field procedures include:
ƒ Installing the system design value forward equalizer and a high value (20 dB or above)
input pad before you install or remove the electronics chassis or activate the system. This
significantly reduces RF signal level and avoids possible EOS which can damage the
hybrids.
ƒ Leaving the input 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.
ƒ Avoiding handling of the hybrids. If you need to remove or install the hybrids, follow proper
ESD grounding practices as stated under Bench Setup.
Bench Setup
Proper bench handling practices include:
ƒ Grounding of the test bench with ESD matting on the work surface and wearing a wrist
strap connected to a continuous ground monitor checker. These practices are particularly
important when handling hybrids.
ƒ Terminating all unused ports with a 75-ohm load.
ƒ Securing all electronics module cover screws or removing the cover completely. Loose screws
can cause the BT100 to oscillate and degrade performance.
To successfully setup the BT100, you need to perform the following tasks:
ƒ Forward path alignment
ƒ Return path alignment
ƒ Check powering and surge protection options