book

Build Your Own Transistor Radios

by Ronald Quan

November 2012

Intermediate to advanced

496 pages

12h 12m

English

McGraw-Hill Education TAB

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Tuned Radio-Frequency (TRF) RadiosBlock Diagram of a TRF RadioCircuit Description of a TRF RadioRegenerative RadioBlock Diagram of a Regenerative RadioCircuit Description of a Regenerative RadioReflex RadioBlock Diagram of a Reflex RadioCircuit Description of a Reflex RadioSuperheterodyne RadioBlock Diagram of a Superheterodyne RadioCircuit Description of a Superheterodyne RadioSoftware-Defined Radio Front-End CircuitsBlock Diagram of a Software-Defined Radio Front EndDescription of Front-End Circuits for a Software-Defined Radio SystemComparison of the Types of Radios
Alignment ToolsTest GeneratorsInductance MeterCapacitance MeterOscilloscopesRadio Frequency (RF) Spectrum AnalyzersWhere to Buy the Tools and Test Equipment

Antenna CoilsVariable CapacitorsTransistorsEarphonesSpeakersPassive ComponentsVector and Perforated BoardsHardwareParts Suppliers
The Continuous-Wave SignalThe Amplitude-Modulated SignalFirst Project: A CW RF Test OscillatorModulator Circuit for the CW GeneratorParts ListAlternate CircuitsParts List
Design Considerations for TRF RadiosImproving Sensitivity and/or Selectivity via Antenna Coils or CircuitsFirst Design of TRF RadioParts ListCircuit DescriptionVariation of the Design (Alternate Design of the TRF Radio)Parts ListAuthor’s Earlier TRF Designs
Motivation Behind Amplifying Both Radio-Frequency and Audio-Frequency SignalsOne-Transistor TRF Reflex RadioParts ListMultiple-Transistor Reflex Radio CircuitParts List
Improving Sensitivity by RegenerationImproving Selectivity by Q Multiplication via RegenerationDesign Considerations for a Regenerative RadioParts ListParts ListParts List
Commercially Made Transistorized Superheterodyne RadiosA Four-Transistor Radio SchematicParts ListAn Eight-Transistor RadioParts ListAlternative Oscillator and Antenna Coil CircuitAn Item to Note
Design Goals for Low PowerLow-Power Oscillator, Mixer, and Intermediate-Frequency CircuitsLow-Power Detector and Audio Circuits“First” Design of a Low-Power Superheterodyne RadioParts ListAlternative Low-Power Superheterodyne Radio DesignParts ListPhotos of Low-Power AM Superheterodyne Radios
A One-Transistor Superheterodyne RadioDesign Considerations for a One-Transistor Superheterodyne RadioParts ListA Two-Transistor Superheterodyne RadioParts List
Ceramic FiltersParts ListGyrators (aka Simulated or Active Inductors)Inductor-less (aka Coil-less) Superheterodyne RadioParts List
SDR Front-End Circuits, Filters, and MixersPhasing Circuits for 0- and 90-Degree Outputs for I and Q SignalsMultipliers for Generating 0- and 90-Degree PhasesExample Radio Circuits for Software-Defined RadiosParts ListSecond SDR Front-End Circuit for the 40-Meter Amateur Radio BandParts List
One-Transistor OscillatorDifferential Pair OscillatorReferences
Adding Circuits Versus Mixing CircuitsDistortion Can Be a Good Thing (for Mixing)Single-Bipolar-Transistor DistortionSimple Transistor Mixer and Its Conversion TransconductanceDifferential-Pair MixerHarmonic Mixer CircuitsMixer Oscillator CircuitsConversion GainReferences
Sampling Signals as a Form of Muliplication or MixingFinite Pulse-Width SignalsAliasing Is a Mixing EffectMultiplexer Circuits as Balanced MixersTradeoffs in Performance of the MixersReferences
Introduction to Suppressed-Carrier Amplitude ModulationHow I and Q Signals Are GeneratedDemodulating I and Q SignalsI and Q Signals Used in Software-Defined Radios (SDRs)References
IF AmplifiersGain-Controlled IF AmplifiersConsiderations of Distortion Effects on IF AmplifiersReferences
Average Envelope DetectorsPower DetectorsSynchronous DetectorsIQ Detectors for AM Broadcast SignalsMeasuring an Average Carrier or Providing Automatic Volume ControlReferences
Introduction to Operational AmplifiersAmplifier CharacteristicsConnecting Multiple Amplifiers for an Amplifier SystemPractical Considerations for Using AmplifiersReferences
Simple Parallel and Series Resonant CircuitsResonant Circuits in OscillatorsExamples of Band-Pass and Band-Reject FiltersReferences
What Is an Image Signal?Methods to Reduce the Amplitude of the Image SignalAnalysis of an Image-Rejection Mixer Using I and Q SignalsAnalysis of the Image-Reject MixerConsequences of an Imperfect 90-Degree Phase Shifter on Reducing the Image SignalReferences
Sources of Random Electronic Noise and Some Basic Noise Theory Paralleling Transistors for Lower NoiseDifferential-Pair Amplifier NoiseCascode Amplifier NoiseSelecting Op AmpsReferences
Update on the One-Transistor Superheterodyne Radio 41Comments on SDR 40-Meter Front-End CircuitExperimenting with Mixers and Using the Spectran Spectrum Analyzer ProgramConducting Experiments on Op Amps and AmplifiersExperiments with a Resonant CircuitThevenin-Equivalent CircuitAnalyzing a Bridge CircuitSome Final Thoughts on the BookReferences

Content preview from Build Your Own Transistor Radios

Appendix 3Short Alignment Procedure for Superheterodyne Radios

IF Transformer Alignment

With a modulated 455-kHz signal, place the signal generator’s output via a wire near the antenna coil or loop antenna. Set the variable capacitor to maximum capacitance or fully closed. With the earphone or loudspeaker, listen for the modulating signal and adjust each of the IF transformers for maximum volume.

Oscillator Coil and Trimmer Capacitor Adjustments

With the variable capacitor’s trimmer capacitors for the RF and Oscillator sections set to half capacitance, provide a modulated 540-kHZ source (or 537-kHz source from Chapter 4) by coupling a wire near the antenna coil or loop antenna. Set the variable capacitor to an almost fully closed position with ...