Guide to Reading Schematic Diagrams--Article Index

TABLE OF CONTENTS:

SECTION 1. TYPES OF ELECTRONIC DIAGRAMS: Schematic Diagrams - Block Diagrams - Chassis-Layout Diagrams - Photos and Pictorial Diagrams - Mechanical Diagrams-Review of Fundamentals

SECTION 2. RESISTORS: What Is a Resistor?-Fixed Resistors-Tapped and Adjust able Resistors-Variable Resistors-Special Resistors

SECTION 3. CAPACITORS: What Is a Capacitor?-Capacitance-Fixed Capacitors Electrolytic Capacitors-Variable Capacitors-Code Letters

SECTION 4. COILS AND TRANSFORMERS: What Is a Coil?-Air-Core Coils-Powdered-Iron Coils Iron-Core Chokes-Transformers

SECTION 5. ELECTRON TUBES: Diode Tubes-Tube Bases-Triode Tubes-Tube Voltages--Symbols-Tetrode Tubes-Pentode Tubes-Beam-Power Tubes-Pentagrid Tubes-Dual-Section Tubes-Gas-Filled Tubes - Phototubes - Electron-Ray Tubes - Cathode-Ray Tubes-Code Letters

SECTION 6. SEMICONDUCTORS: What Is a Semiconductor? - Rectifiers - Signal Diodes -Transistors-Other Semiconductors

SECTION 7. SWITCHES AND RELAY: SPST Switches-SPDT Switches-Double-Pole Switches Wafer Switches-Push-Button Switches-Relays

SECTION 8. MISCELLANEOUS COMPONENTS: Antennas-Speakers-Fuses-Circuit Breakers-Lamps Batteries-Crystals-Vibrators-Microphones-Transducers - Headsets and Earphones - Phono Pickups - Tape Heads - Rotating Machines - Solenoids - Meters - Other Symbols

SECTION 9. CONNECTING THE COMPONENTS: Wires-Ground and Chassis Symbols-Other Methods of Denoting Connections - Connecting Devices - Printed Circuits-Component Combinations

SECTION 10. COMBINING THE COMPONENTS: Rectifier Circuits-Basic Tube Circuits-Basic Transistor Circuits-Summary

SECTION 11. READING AND INTERPRETING SCHEMATIC DIAGRAMS: Radio-Receiver Schematic Analysis-Transistor Radios From Schematic to Chassis-Other Types of Equipment

SECTION A. HOUSE WIRING SYMBOLS

SECTION B. ANSWERS TO QUIZ QUESTIONS

OVERVIEW

Who would think of starting on a cross-country trip with out first consulting a road map and plotting the route? Schematic diagrams and road maps have a lot in common-both show the "highways" from one point to another, and both use symbols to designate the various "landmarks." Yet, many students try to embark on a much more important trip--a career in electronics--without first learning how to properly read the "road maps" of the trade.

A simple key to the symbols, such as that included on most maps, is not sufficient for electronic schematics. The high ways, cities, rivers, etc., on the road map are familiar to everyone--you immediately have a picture of what is being represented. The components which make up electronic circuits, however, are not as familiar. Before you can look at an electronic symbol and get a mental picture of its effect on the circuit, you must first know something about the component it represents. This guide was written to help you gain this needed understanding. The comments and letters received have indicated this goal has been accomplished. This second edition contains many added symbols and expanded explanations to keep in step with the latest developments.

Only the theory considered necessary for this knowledge is given. Once the purpose of a component is understood, you will see that its symbol is just as representative as the line across a map is of a highway.

The later Sections in this guide show how these components are combined to form circuits. Then, step by step, you follow signals through a schematic diagram of a radio receiver. The function of each stage and the meaning of the information on the schematic is explained.

This guide has been written with the beginner or hobbyist in mind, but it can also serve as an invaluable reference for the technician.

Also see:

Complete Guide To Reading Schematic Diagrams (1972)

Guide to Linear Analog Circuits