Service manual

Soldering
Printed Circuit
Boards
The etched circuit boards in the multimeter 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.
CAUTION
Do not use a sharp metal object such as an awl or twist drill, since
sharp objects may damage the plated-through conductor.
• 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
(a 38-watt soldering iron is recommended), 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
the equipment is properly grounded to prevent electrostatic
discharge from damaging CMOS devices.
Post-Repair
Safety Checks
After making repairs to the Agilent E1326B multimeter, inspect the
multimeter 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 run the self-test (*TST? command) to verify that the multimeter is
functional.
Service 8-9