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CONSTRUCTION
Introduction
Assembly of your TCT-255 Multi-Network Cable Tester Kit will prove to be an exciting project
and give you much satisfaction and personal achievement. If you have experience in soldering
and wiring techniques, then you should have no problem with the assembly of this kit. Care
must be given to identifying the proper components and in good soldering habits. Above all,
take your time and follow these easy step-by-step instructions. Remember, “An ounce of
prevention is worth a pound of cure”. Avoid making mistakes and no problems will occur.
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 and the board is turned to solder the
component leads on the foil side. Solder immediately unless the pad is adjacent to another
hole which will interfere with the placement of the other component. Cut excessive leads with
a diagonal cutter. Then, place a check mark in the box provided next to each step to indicate
that the step is completed. Be sure to save the extra leads for use as jumper wires if needed.
Soldering
The most important factor in assembling your cable tester 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. Many areas on the PC board are close together and care must be given not to form
solder shorts. Size and care of the tip will eliminate problems.
For a good soldering job, the areas being soldered must be heated sufficiently so that the
solder flows freely. Apply the solder simultaneously to the component lead and the component
pad on the PC board so that good solder flow will occur. Be sure that the lead extends through
the solder smoothly indicating a good solder joint.
Use only rosin core solder of 63/37 or
60/40 alloy.
DO NOT USE ACID CORE SOLDER! Do not blob the solder over the lead because this can
result in a cold solder joint.
Heat Sinking
Electronic components such as transistors,
IC’s, and diodes can be damaged by the heat
during soldering.
Heat sinking is a way of
reducing the heat on the components while
soldering.
Dissipating the heat can be
achieved by using long nose pliers, an alligator
clip, or a special heat dissipating clip. The heat
sink should be held on the component lead
between the part and the solder joint.
Mount Part
Bend Leads to Hold Part
Solder and Cut Off Leads
Foil Side
Rx - 100
W
5% 1/4W Resistor
(brown-black-brown-gold)
Heat Sink
(this can be ordered as part of Elenco’s Solder Ease
Kit Model SE-1).
Soldering Iron
Solder
Heat Sensitive
Component (Diode)
PC Board
Figure 6
