Instruction manual

-4-
What Good Soldering Looks Like
A good solder connection should be bright, shiny,
smooth, and uniformly flowed over all surfaces.
Soldering a PC board
1. Solder all components
from the copper foil side
only. Push the soldering
iron tip against both the
lead and the circuit board
foil.
2. Apply a small amount of
solder to the iron tip. This
allows the heat to leave
the iron and onto the foil.
Immediately apply solder
to the opposite side of the
connection, away from
the iron. Allow the heated
component and the circuit
foil to melt the solder.
3. Allow the solder to flow
around the connection.
Then, remove the solder
and the iron and let the
connection cool. The
solder should have flowed
smoothly and not lump
around the wire lead.
4.
Here is what a good
solder connection looks
like.
Types of Poor Soldering Connections
1. Insufficient heat - the
solder will not flow onto
the lead as shown.
2. Insufficient solder -
let the solder flow over
the connection until it is
covered. Use just
enough solder to cover
the connection.
3. Excessive solder -
could make
connections that you
did not intend to
between adjacent foil
areas or terminals.
4. Solder bridges - occur
when solder runs
between circuit paths
and creates a short
circuit. This is usually
caused by using too
much solder. To correct
this, simply drag your
soldering iron across
the solder bridge as
shown.
A poorly soldered joint can greatly affect small current flow in circuits and can cause equipment failure. You can damage
a PC board or a component with too much heat or cause a cold solder joint with insufficient heat. Sloppy soldering can
cause bridges between two adjacent foils preventing the circuit from functioning.
Solder
Soldering Iron
Foil
Solder
Soldering Iron
Foil
Component Lead
Soldering Iron
Circuit Board
Foil
Rosin
Soldering iron positioned
incorrectly.
Solder
Gap
Component Lead
Solder
Soldering Iron
Drag
Foil
TROUBLESHOOTING
1. One of the most frequently occurring problems is poor
solder connections.
a) Tug slightly on all parts to make sure that they
are indeed soldered.
b) All solder connections should be shiny.
Resolder any that are not.
c) Solder should flow into a smooth puddle rather
than a round ball. Resolder any connection that
has formed into a ball.
d) Have any solder bridges formed? A solder
bridge may occur if you accidentally touch an
adjacent foil by using too much solder or by
dragging the soldering iron across adjacent foils.
Break the bridge with your soldering iron.