Introduction 1
1 Introduction to RF electronics 1
The electromagnetic spectrum 1
Units and physical constants 2
Microwave letter bands 5
RF components, layout, and construction 7
Coaxial cable transmission line( coax ) 14
Warning 18
Vectors 19
Tuned resonant circuits 19
2 RF components and tuned circuits 19
Inductance and inductors 21
Capacitors and capacitance 33
Voltage and current in capacitor circuits 40
Tuned RF/IF transformers 51
3 Variable capacitors in RF circuits 59
Straight-line capacitance vs straight-line capacitors 63
Special variable capacitors 64
Varactor applications 69
Note and warning! 70
4 Winding your own coils 73
Amidon Associates coil system 74
Making your own toroid-core inductors and RF transformers 77
Ferrite and powdered-iron rods 92
Project 4-1 95
References 104
5 Radio receivers: Theory and projects 105
The tuner 106
Tuned radio-frequency(TRF)receivers 110
Superheterodyne receivers 112
Receiver circuits you can build 126
Basic theory of operation 143
6 Direct-conversion radio receivers 143
Problems associated with DCR designs 146
Some practical design approaches 156
References and notes 170
7 RF amplifier and preselector circuits 171
JFET preselector circuits 173
MOSFET preselector circuits 176
Noise and preselectors 179
Broadband RF preamplifier for VLF, LF, and AM BCB 179
Broadband RF amplifier(50-Ωinput and output) 187
Broadband or tuned RF/IF amplifier using the MC-1350P 188
VLF preamplifier 189
Conclusion 192
8 Building IF amplifiers 193
Amplifier circuits 193
Cascode pair amplifier 195
Universal IF amplifier 196
Coupling to other filters 200
IC IF amplifiers 200
IF processing Ics 203
Successive detection logarithmic amplifiers 203
Filter switching in IF amplifiers 205
References 206
9 Interpreting radio receiver specifications 207
A hypothetical radio receiver 207
Units of measure 211
Dynamic performance 230
Dynamic range 235
Receiver improvement strategies 240
References 241
10 Building signal-generator and oscillator circuits 243
Types of oscillator circuits 243
1-to 20-MHz crystal oscillator 245
HF/VHF buffer amplifier 247
455-kHz AM IF-amplifier test-and -alignment oscillator 248
Signal generator for the AM and short-wave bands 249
11 RF directional couplers 253
Conclusion 257
References 257
12 The RF hybrid coupler 259
Applications of hybrids 259
Phase-shifted hybrids 262
Conclusion 264
13 Building simple VLF radio receivers 267
Receiver types 268
Tuning circuit problems 270
A VLF receiver project 276
References and notes 284
14 What s that mess coming from my receiver? 285
Radio station interference 285
Other interference 289
15 Filtering circuits against EMI 293
Means of EMI transmission 293
Electronic noise 295
Counters to EMI 296
Common mode and differential currents 298
AC power line filtering 302
Special medical EMI problems 302
Computer EMI 303
Conclusion 304
16 Measuring inductors and capacitors at RF frequencies 305
VSWR method 305
Voltage divider method 307
Frequency-shifted oscillator method 309
Signal generator method 309
Using RF bridges 310
Finding parasitic capacitances and inductances 315
Conclusion 317
17 Building and using the RF noise bridge 319
Adjusting antennas 321
Resonant frequency 322
Impedance matching approaches 322
Capacitance and inductance measurements 324
18 Vectors for RF circuits 327
19 Impedance matching: Methods and circuits 331
L-section network 332
Pi-(π)networks 334
Split-capacitor network 335
Transmatch circuit 335
Coaxial cable balun transformaers 338
Matching stubs 338
Quarter-wavelength matching sections 339
Series-matching section 340
20 Using the double-balanced mixer(DBM) 343
Diplexer circuits 344
JFET and MOSFET doubly balanced mixer circuits 347
Doubly balanced diode mixer circuits 350
Bipolar transconductance cell DBMs 355
Preamplifiers and postamplifiers 359
Conclusion 363
References 363
21 PIN diodes and their uses 365
PIN diode switch circuits 366
PIN diode applications 369
Conclusion 373
22 UHF and microwave diodes, transistors, and integrated circuits 375
Diode devices 375
Introduction to negative resistance(-R)devices 382
UHF and microwave RF transistors 399
Semiconductor overview 400
Selecting transistors 413
23 LC RF filter circuits 431
Low pass, high pass, bandpass, and notch 431
Filter applications 432
Filter construction 434
Filter design approach 435
Low-pass filters 435
High-pass filters 437
Bandpass filters 440
Notch filters 443
More on bandpass filters 447
Conclusion 447
24 Time-domain reflectometry on a budget 449
The basis of TDR 449
The pulse source 450
Test set-up 451
Some actual measurements 451
25 Solving frequency drift problems 455
Frequency shift problems 455
Drift problems 457
VHF problems 458
Problems with older equipment 462
Heat problems 462
Equipment modifications 462
26 The Smith chart 463
Smith chart components 463
Smith chart applications 475
27 Detector and demodulator circuits 487
AM envelope detectors 487
Balanced demodulators 494
Noise 494
Synchronous AM demodulation 495
Double-sideband(DSBSC)and single-sideband(SSBSC) suppressed carrier demodulators 495
FM and PM demodulator circuits 502
Discriminator circuits 503
Ratio detector circuits 504
Pulse-counting detectors 506
Phase locked loop FM/PM detectors 507
Quadrature detector 508
Index 511
About the author 534