Agilent Technologies E1364A service manual Repair and Maintenance Guidelines, ESD Precautions

Repair and Maintenance Guidelines

ESD Precautions

Soldering Printed Circuit Boards

Post-Repair Safety Checks

This section provides guidelines for repairing and maintaining the E1364A Switch Module, including:

•ESD precautions

•Soldering printed circuit boards

•Post-repair safety checks

Electrostatic discharge (ESD) may damage static sensitive devices in the E1364A Switch Module. This damage can range from slight parameter degradation to catastrophic failure. When handling switch assemblies, follow these guidelines to avoid damaging switch components:

•Always use a static-free work station with a pad of conductive rubber or similar material when handling switch components.

•If a device requires soldering, be sure the assembly is placed on a pad of conductive material. Also, be sure that you, the pad, and the soldering iron tip are grounded to the assembly.

Some of the components on the etched circuit boards in the switch have plated through-holes that allow a solder path to both sides of the insulating material. Soldering can be done from either side of the board with equally good results. When soldering to any circuit board, keep in mind the following guidelines:

•Avoid unnecessary component unsoldering and soldering. Excessive replacement can result in damage to the circuit board and/or adjacent components.

•Do not use a high-power soldering iron on etched circuit boards, as excessive heat may lift a conductor or damage the board.

•Use a suction device or wooden toothpick to remove solder from component mounting holes. When using a suction device, be sure that the equipment is properly grounded.

After making repairs to the E1364A Switch Module, inspect the switch for any signs of abnormal internally generated heat, such as discolored printed circuit boards or components, damaged insulation, or evidence of arcing.

Determine and correct the cause of the condition. Then perform the Functional Verification Test described in Chapter 2 to verify that the switch is functional.

46 Service Chapter 4