Construction, Introduction, Safety procedures – Elenco Logic Pulser Kit User Manual

Page 4: Assemble components, What good soldering looks like, Types of poor soldering connections

Advertising
background image

-3-

Introduction

The most important factor in assembling your LP-425K Logic Pulser Kit is good soldering techniques. Using the
proper soldering iron is of prime importance.

A small pencil type soldering iron of 25 - 40 watts is

recommended.

The tip of the iron must be kept clean at all times and well tinned.

Safety Procedures

• Wear eye protection when soldering.
• Locate soldering iron in an area where you do not have to go around it or reach over it.

Do not hold solder in your mouth. Solder contains lead and is a toxic substance. Wash your hands
thoroughly after handling solder.

• Be sure that there is adequate ventilation present.

Assemble Components

In all of the following assembly steps, the components must be installed on the top side of the PC board unless
otherwise indicated.

The top legend shows where each component goes.

The leads pass through the

corresponding holes in the board and are soldered on the foil side.
Use only rosin core solder of 63/37 alloy.

DO NOT USE ACID CORE SOLDER!

CONSTRUCTION

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

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.

1.

Insufficient heat

- the

solder will not flow onto the
lead as shown.

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.

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.

What Good Soldering Looks Like

A good solder connection should be bright, shiny,
smooth, and uniformly flowed over all surfaces.

Types of Poor Soldering Connections

Foil Side

Mount Part

Bend Leads to

Hold Part

Solder and

Cut Off Leads

Advertising