TAG MCLAREN AUDIO 100 5R Series, Service Manual

Page: 6 / 34

F3 series 100X5R service manual 2
1.3 Soldering
How to de-solder components
Components should be removed, wherever possible, using a de-soldering
tool. Be careful not to damage tracks and pads by applying too much
pressure.
How to make good solder joints
1. Ensure surfaces are clean.
2. Keep soldering iron clean and wetted with solder. Use
an appropriate bit. Do not leave soldering iron on when
not in use.
3. Apply soldering iron to both component lead and pad
before applying solder. Make sure that the soldering
iron is applied long enough for the solder to wet
properly, but do not apply for too long or component
damage may occur.
4. Allow a small gap between component body and pad.
Solder must not reach the base of the component.
How to detect acceptable joints
1. Solder joints should have from a shiny to satin lustre and
a generally smooth appearance.
2. Solder should have wetted both the component lead
and pad.
3. There should be a concave meniscus between the
objects being soldered. The angle of solder to pad
should be less than 90
E
unless the solder joint extends
over the edge of the pad.
4. Solder should fill the component pad and wet
component lead around the full circumference (360
E ).
How to detect unacceptable joints
1. Poor wetting produces a bead of solder. The fillet will be convex instead of concave,
and there will not be a feather edge.
2. On double-sided PCBs, solder should wet all round plated-through hole, on both
sides of the PCB.