Page 137 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

3 Compression Connectors
Description: Compression connectors use a mechanical compression force to join conductors together within a
connector or terminal block.
Advantages: Provides a reliable and gas-tight connection, resistant to environmental factors such as moisture
and corrosion.

Applications: Commonly used in power distribution systems, telecommunications, and RF coaxial cables.
4 Press-Fit Connections:
Description: Press-fit connectors feature pins or terminals that are pressed into plated through-holes on a PCB
without soldering.
Advantages: Offers a high-density, reliable connection without the need for soldering. Facilitates easy assembly
and disassembly.

Applications: Used in PCB manufacturing, backplane assemblies, and modular electronic systems.
5 Mechanical Fasteners:
Description: Mechanical fasteners such as screws, nuts, bolts, and clips are used to secure components or
terminals together.
Advantages: Provides a strong and easily reversible connection. Allows for easy maintenance and repair.
Applications: Widely used in electrical enclosures, panel assemblies, and grounding systems.
6 Twist-On Wire Connectors:
Description: Twist-on wire connectors feature insulated caps with internal threads that twist onto the exposed
ends of wires to form a connection.
Advantages: Provides a quick and convenient way to join multiple wires together. Offers electrical insulation and
strain relief.
Applications: Used in residential and commercial electrical wiring, lighting fixtures, and junction boxes.
Considerations
Electrical Performance: Ensure that the chosen method provides adequate electrical conductivity, insulation,
and reliability for the application.
Environmental Factors: Consider the operating environment, including temperature, humidity, vibration, and
exposure to chemicals or contaminants.
Ease of Assembly: Evaluate the ease of assembly, maintenance, and repair, especially for applications requiring
frequent modifications or upgrades.

Construction of Printed Circuit Boards (PCB)

1 Single-Layer PCBs:
Substrate: Typically made of a non-conductive material such as fiberglass (FR-4).
Copper Layer: A single layer of copper foil is laminated onto one side of the substrate.

Etching: The unwanted copper is removed using chemical etching, leaving behind the desired circuit traces.
Through-Hole Plating (Optional): Holes are drilled for component leads and plated to provide electrical connections.
2 Double-Layer PCBs:
Substrate: Similar to single-layer PCBs but with copper foil laminated on both sides of the substrate.

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CITS : E & H - Electronics Mechanic - Lesson 73 - 76