Basic Radio Course
Table of Contents
THE ELECTRON THEORY | The nucleus, Electron attraction, Positive and negative, Conductors, Isolators, Electromotive force, Coulomb, Amperes and milliamperes, Resistance, Ohms and megohms, Voltage |
OHM'S LAW AND THE RESISTOR | Current flow, Ohm's law, using Ohm's law, Fixed and variable resistors, Carbon and wire wound resistors, Rheostats and potentiometers, The volume control, Why resistance is important, Voltage division, Heat and power, Wattage |
WHAT IS INDUCTION? | Electron motion, Magnetic field, Left-hand rule, The inductor, Magnetic lines of force, Magnetism induces current, Self-induction, Bucking voltage, Inductance, The henry, Inductors and chokes |
CAPACITANCE | Capacitors, Stray capacitance, Charge, Dielectric, Charge storage, Farad, Dielectric constant, Leakage, Power factor, Capacitor construction |
HOW CAPACITANCE ARE MADE | Interleaved plates, Variable air capacitor, Mica capacitors, The silvered mica, Paper capacitors, Oil-filled types, Electrolyics, Oxide film, The dry electrolytic, Etched foil, Fabricated-plate electrolytics, Polarization, Ceramic capacitors, Temperature coefficient |
REACTANCE, IMPEDANCE AND PHASE | The tuned circuit, Phase : leading and lagging, In phase, Phase shift, Rate of change of current, Induced e.m.f, Capacitive reactance, Inductive reactance, Equivalent resistance, Impedance |
RESONANT CIRCUITS | Series- and parallel-tuned circuits, Resonant frequency, Figure of merit or "Q", Parallel circuits, Tuned-circuit loading, Wave traps, Tuning resonant circuits, Inductive and capacitive tuning |
TRANSFORMERS-HOW THEY WORK | High voltage or high current, Primary coil, Secondary coil, Cores, Air core, Transformation ratios, Turns ratio, Magnetic flux, Lenz's law, Magnetizing current, Hysteresis and eddy-current losses, Magnetic inertia, Laminated cores, Transformer applications and troubles |
THE DIODE VACUUM TUBE | Experimental setup, Plate (anode), Filament, A-and B-batteries. Kinetic energy, Electron emission, Indirectly heated cathode, Plate current, Saturation current, Diodes, Gassey tubes, Weak, noisy and microphonic tubes |
TRIODE AND TETRODE TUBES | Coated filaments, Thorium, Filament temperature, Space charge, Mercury vapor, Enter the triode, Control grid, Bias, Electrode arrangement, Amplification factor, Plate-load resistor, Coupling capacitor, The screen grid, The tetrode, Circuit of a tetrode amplifier |
THE PENTODE VACUUM TUBE | Secondary emission, Tetrode curve, The suppressor grid, Suppressor alters curve, The beam tube, Tube types, Hybrid tubes, Compactrons, |
VACUUM-TUBE CHARACTERISTICS | The graph, Plotting curves, Test circuit, Plate-family curves, Transfer characteristic, Amplification factor, Plate resistance, Transconductance, Mutual conductance, Mho and micromho, Dynamic characteristics, Load line, Voltage gain |
THE POWER SUPPLY | B-supply rectifiers, Half- and full-ware rectifiers, Smoothing filters, Choke-input filter, Capacitor-input filter, Power supply troubles |
POWER SUPPLY TYPES | A.c.-d.c. supply, Ballast resistor, Transformerless heater string, Line-cord resistor, Typical a.c-d.c supply, Three-way supply, Voltage-doubler supply, Auto-radio supplies, Nonsynchronous vibrator power supply, Synchronous vibrator power supply, Transistor d.c-d.c converter |
SOUND AND SPEAKERS | Brief review of sound. Compression and rarefaction of sound. Frequency. Pitch. Loudness. The dynamic speaker. Field coil. Spider. Frame. Permanent magnets. Sound and the ear. Low-note difficulties. Sound-pressure curve. Repair problems. |
THE POWER OUTPUT STAGE | Voice-coil impedance. The output stage. Plate resistance. Conditions for maximum transfer of power. Output transformer. Turns ratio. Universal output transformer. |
THE VOICE AMPLIFIER | Audio voltage amplifier. Distortion. Power. Voltage amplification verses load resistance. Phase inversion. Triode dynamic characteristics. Push-pull amplifier. Harmonics. Fundamental wave. Harmonic distortion. |
DEMODULATING THE R.F. | Modulation. Detector or demodulator. R.F. carrier envelope. Demodulating the signal. Rectify the R.F. Simple crystal set. Crystal detector. Vacuum tube diode detector. Grid-leak detector. Power detector. R.F. choke. |
RECEIVER SELECTIVITY | Getting better selectivity. Basic tuned-radio frequency (t.r.f) circuit. Cascaded R.F stages. Tuned-circuit frequency response. I.f. transformers. The superheterodyne. A converter tube. The intermediate frequency. Trimmer-tuned and slug-tuned transformers. Coupling. Critical coupling. How much bandwidth. Defects in the i.f. stage. |
THE CONVERTER STAGE | Mixers. Beat frequencies. How a mixer works. Why detection? Triode mixer. The mixer tube. Image rejection. More sophisticated circuits. Pentagrid converter. Triode-hexode mixer circuit. |
SOME OSCILLATOR CIRCUITS | Dampened oscillation. Driven oscillator. Vacuum-tube oscillator. Tickler coil. Circuit variations. Armstrong, Meissner, Hartley and Colpitts oscillators. Oscillator tracking. Padder capacitor. |
HOW TO TRAP A SIGNAL | Snaring the signal. High-impedance loop antenna. . Loopstick. Directional properties. Improved loop antennas. |
SIGNALS IN SPACE | Ground waves. Sky waves. The ionosphere layer. Fading. Automatic volume control. The detector circuit. Remote-cutoff tubes. Delayed a.v.c |
TRANSISTOR RADIOS | How transistors are made. Electrons and holes as current carriers. N- and P-type material. Leakage. Breakdown or avalanche voltage. Semiconductor rectification. Inside the transistor. Transistors compared to vacuum tubes. Transistor receiver circuits. Printed circuits and service techniques. |
SERVICING TECHNIQUES | Troubleshooting methods. Voltage measurement. Leaky capacitors. Open transformers. Service manuals. Resistance measurements. Circuit disturbance testing. Signal-injection testing. Signal-tracing method. |
INSTRUMENTS AND TOOLS | A versatile instrument. V.o.m. Basic circuitry. V.t.v.m. Signal generator. Tube tester. Signal tracer. Other tools you need. |