3
Selection
and Operation
of Wireless Microphone Systems
TABLE OF CONTENTSIntroduction . . . . . . . . . . . . . . . . . . . . . . . .4
PART ONE
WIRELESS MICROPHONE SYSTEMS:
HOW THEYWORK
CHAPTER 1
BASIC RADIOPRINCIPLES . . . . . . . . . . 5
Radio Wave Transmission . . . . . . . . . . . . . 5
Radio Wave Modulation . . . . . . . . . . . . . . 7
CHAPTER 2
BASIC RADIOSYSTEMS . . . . . . . . . . . . 8
System Description . . . . . . . . . . . . . . . . . . 8
Input Sources . . . . . . . . . . . . . . . . . . . . . .8
Transmitter: General Description . . . . . . . . 9
Transmitter: Audio Circuitry . . . . . . . . . . . 10
Transmitter: Radio Circuitry . . . . . . . . . . . 11
Receiver: General Description . . . . . . . . . 12
Receiver: Radio Circuitry . . . . . . . . . . . . . 12
Receiver: Audio Circuitry . . . . . . . . . . . . . 14
Receiver: Squelch . . . . . . . . . . . . . . . . . . 14
Receiver: Antenna Configuration . . . . . . . 15
Multipath . . . . . . . . . . . . . . . . . . . . . . . . . 15
New! Receiver: Diversity Techniques . . 16
New! Antennas . . . . . . . . . . . . . . . . . . . 18
New! Antenna Cable . . . . . . . . . . . . . . .20
Antenna Distribution . . . . . . . . . . . . . . . . . 20
CHAPTER 3
WIRELESS SYSTEM OPERATION . . . . .22
New! Frequency Bands for
Wireless Systems . . . . . . . . . . . . . . . . . . . 22
VHF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
UHF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
New! Frequency Selection . . . . . . . . . . . 24
System Compatibility . . . . . . . . . . . . . . . .25
Operating Frequency Interactions:
Intermodulation . . . . . . . . . . . . . . . . . . . . 25
Internal Frequency interactions: LO, IF,
Crystal Multipliers . . . . . . . . . . . . . . . . . . . 26
Non-System Radio Interference . . . . . . . .28
New! Broadcast Television . . . . . . . . . . .28
Broadcast Radio . . . . . . . . . . . . . . . . . . . . 31
Other Radio Services . . . . . . . . . . . . . . . . 31
Non-Broadcast Sources . . . . . . . . . . . . . . 31
Spread Spectrum Transmission . . . . . . . . 32
Range of Wireless Microphone Systems . 33
New! Digital Wireless Systems . . . . . . . 34
New! Operation of Wireless Systems
Outside of the U.S. . . . . . . . . . . . . . . . . .35
PART TWO
WIRELESS MICROPHONE SYSTEMS:
HOW TOMAKETHEM WORK
CHAPTER 4
WIRELESS SYSTEM
SELECTION AND SETUP . . . . . . . . . . . 36
New! System Selection . . . . . . . . . . . . .36
New! Crystal Controlled vs.
Frequency Synthesis . . . . . . . . . . . . . . . .37
System Setup: Transmitter . . . . . . . . . . . . 37
System Setup: Receivers . . . . . . . . . . . . . 39
System Setup: Receiver Antennas . . . . . . 42
System Setup: Batteries . . . . . . . . . . . . . . 43
System Checkout and Operation . . . . . . . 43
Troubleshooting
Wireless Microphone Systems . . . . . . . . . 44
Troubleshooting Guide . . . . . . . . . . . . . .45
CHAPTER 5
APPLICATION NOTES . . . . . . . . . . . . . 46
Presenters . . . . . . . . . . . . . . . . . . . . . . . . 46
Musical Instruments . . . . . . . . . . . . . . . . . 46
Vocalists . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Aerobic/Dance Instruction . . . . . . . . . . . . 48
Theater . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Worship . . . . . . . . . . . . . . . . . . . . . . . . . .49
Bingo . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Film/Videography . . . . . . . . . . . . . . . . . . .50
Broadcast . . . . . . . . . . . . . . . . . . . . . . . . . 50
New! Point-to-Point Wireless . . . . . . . . . 51
Large Room/Multi-Room Applications . . . 51
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . 54
REFERENCEINFORMATION
Appendix A: Calculation of
Intermodulation Products . . . . . . . . . . . . 55
Appendix B: U.S. Television Channels . . .57
Glossary of Terms and Specifications . . . 58
Included Illustrations . . . . . . . . . . . . . . . . 61
Suggested Reading & Biography . . . . . . 62