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4

ANTENNA SETUP

Wireless Systems Guide for

Introduction

Introduction

The world of professional audio is filled with 

transducers. A transducer is a device that converts

one form of energy to another. In the case of 

microphones and loudspeakers, sound waves are

converted to electrical impulses, and vice versa.

The proliferation of wireless audio systems has 

introduced yet another category of transducer to

professional audio, the antenna. As defined in the

ARRL (American Radio Relay League) Antenna

Book, “The purpose of an antenna is to convert

radio-frequency electric current to electromagnetic

waves, which are then radiated into space.” 

Attached to a receiving device, antennas can also

work in the reverse fashion, converting the 

electromagnetic wave back to an electric current.

This reciprocity is similar to the manner in which

a loudspeaker can also function as a microphone

when attached to an audio input. 

As with any transducer, following certain 

guidelines helps ensure maximum performance.

When dealing with radio frequencies in particular,

considerations such as antenna size, orientation,

and proper cable selection, are important 

factors not to be overlooked. Without getting too 

technical, this guide presents a series of good

practices for most typical wireless audio 

applications. Note that these recommendations

only apply to professional wireless systems with

detachable antennas. For entry-level systems

with permanently affixed antennas, antenna 

distribution and remote antenna mounting are

simply not possible. 

One final note: These recommendations are 

useful guidelines to help achieve satisfactory 

performance from wireless audio systems, but

not hard-and-fast rules that need to be followed

to the letter. However, if a wireless system fails 

to operate as expected, it is often due to the 

disregard of several of these guidelines, 

compounding the negative effects. Rarely 

does a system fail to function if only a single 

recommendation is overlooked!

Содержание ANTENNA SETUP

Страница 1: ...A Shure Educational Publication ANTENNA SETUP WIRELESS SYSTEMS GUIDE By Gino Sigismondi and Crispin Tapia...

Страница 2: ......

Страница 3: ...bution 3 or more receivers 8 Antenna Remoting 8 Antenna Combining 10 Multi room Antenna Setups 10 Antenna Combining for Personal Monitor Transmitters 10 Quick Tips 11 Suggested Reading 11 Section Two...

Страница 4: ...hen attached to an audio input As with any transducer following certain guidelines helps ensure maximum performance When dealing with radio frequencies in particular considerations such as antenna siz...

Страница 5: ...an be mounted directly to the wireless receiver or antenna distribution system this also includes front mounted antennas on the rack ears These antennas require a ground plane for proper reception whi...

Страница 6: ...the front When deciding where to mount antennas always try to maintain line of sight between the receiving and transmitting antennas For example if the back of the rack faces the performance area the...

Страница 7: ...sulting in erratic coverage Additionally closely spaced antennas can aggravate local oscillator bleed which is a potential source of interference between closely spaced receivers Finally for remote an...

Страница 8: ...ncies over a large range typically several hundred Megahertz Narrowband devices may be limited to no more than 20 or 30 MHz Since these are active devices frequencies outside the bandwidth of the dist...

Страница 9: ...ntenna amplifiers are also band specific available as both narrow or wideband Each connection between two sections of cable may result in some additional signal loss depending on the connector To incr...

Страница 10: ...at could result in signal dropout Certain receiver designs will be better equipped to deal with this situation than others but it is a worthwhile precaution nonetheless Antenna Combining for Personal...

Страница 11: ...account Antennas are designed to be sensitive to particular frequencies Be sure to use the proper antenna for the frequency of your wireless system Antenna efficiency degrades somewhat outside of the...

Страница 12: ...a 3 4 receivers 1 active antenna distribution system w 4 outputs 2 receivers 2 passive splitters A antenna B antenna SLX4 SLX4 SLX4 SLX4 UA844 POWER UHF ANTENNA POWER DISTRIBUTION SYSTEM SLX4 SLX4 SLX...

Страница 13: ...w 4 outputs each A antenna B antenna SLX4 SLX4 SLX4 SLX4 UA844 POWER UHF ANTENNA POWER DISTRIBUTION SYSTEM SLX4 SLX4 SLX4 SLX4 UA844 POWER UHF ANTENNA POWER DISTRIBUTION SYSTEM SLX4 SLX4 SLX4 SLX4 UA8...

Страница 14: ...tenna combining 2 4 systems 1 4 to 1 antenna combiner 1 2 3 4 5 6 7 8 PA821 PSM Antenna Combiner 470 870 MHz 50 OHMS ACTIVE COMBINER MAIN OUT INPUT SIGNAL A IN B IN A B OUT POWER Shown Shure PA821 wit...

Страница 15: ...2 3 4 5 6 7 8 PA821 PSM Antenna Combiner 470 870 MHz 50 OHMS ACTIVE COMBINER MAIN OUT INPUT SIGNAL A IN B IN A B OUT POWER Shown Shure PA821 with built in 2 to 1 passive combiner 1 2 3 4 5 6 7 8 PA821...

Страница 16: ...enna 0 dB Amplifier 10 dB 100 RG213 Cable 7 dB Net Gain 3 dB Net Gain Calculation Antenna 0 dB Amplifier 1 3 dB Amplifier 2 10 dB 75 RG8X Cable 10 dB Net Gain 3 dB Net Gain Calculation Antenna 0 dB Am...

Страница 17: ...a 30 feet Net Gain Calculation Antenna 0 dB Amplifier 3 dB 25 RG8X Cable 3 dB Net Gain 0 dB Net Gain Calculation Antenna 0 dB 6 RG58 Cable 1 dB Net Gain 1 dB 30 ft 10 m RG8X 6 ft 2 m RG8X 10 m Many mo...

Страница 18: ...nd recording engineer Gino s experience includes performing and composing and sound design for modern dance and church sound Crispin Tapia Crispin Tapia is an Applications Engineer at Shure Incorporat...

Страница 19: ...e of charge To obtain your complimentary copies call one of the phone numbers listed below or visit www shure com Microphone Techniques for Studio Recording Microphone Techniques for Live Sound Reinfo...

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