Wireless Microphones

A wireless microphone is a microphone without any physical cable connecting. It is directed to the sound recording or amplifying equipment with which it is linked. Usually, it requires a wireless transmitter, and a wireless receiver. The transmitter either is connected by a short cable to a body pack transmitter built or is into the microphone. The wireless transmitters require a broadcast and battery through an external antenna or internal antenna. The wireless receiver is tuned to electromagnetic wavelength as same to the transmitter. It is physically attached to an output device like a closed system headset or a PA system.

Here now we need to know how a wireless microphone works. So the wireless microphone system consists of a microphone, a transmitter and, a receiver.

In a conventional wired microphone sound waves are converted into an electrical audio signal which travels to the PA system through a cable. A wireless microphone system is advanced. It converts the audio signal created by the microphone to a radio signal or an Infrared signal.

Transmitters are of two basic types.

• Body-pack transmitter
• Belt-pack transmitter

Body-pack transmitter and Belt-pack are like a small box about the size as a TV remote control. The transmitter clips to the user's belt are worn on the body.

In the handheld wireless microphone, the transmitter is fixed into the handle of the microphone, making it a wireless mic which is slightly larger than a standard wired microphone. These types of all the wireless transmitters require a battery to work.

The receiver works to catch the signal broadcast by the transmitter and change it back into an audio signal.

§         Single antenna receivers

A single antenna receiver consists of one receiving antenna and one tuner antenna, similar to that of an FM radio. Single antenna receivers work well in many applications. But sometimes focus to temporary interruptions or dropouts in the signal occur.

§         Diversity receivers

A diversity receiver provides better performance. A diversity receiver consists of two separate antennas fixed a short distance apart and usually having two separate tuners. The intelligent circuit present in the receiver automatically selects the better one of the two signals. Here the chances of a dropout are greatly reduced.

• Handheld microphone looks like a normal wired microphone, but have a bigger body to house the transmitter and battery pack.
• Plug-on or cube-style transmitters are attached to the bottom of the standard microphone, converting it into wireless operation.
• Bodypack is a small box accommodating the transmitter and battery pack, but not the microphone. It can be attached to a belt or elsewhere and have a wire going to headset, or a lavalier microphone.

• Gives freedom of movement for the artist or speaker.
• No cabling problems common with wired microphones, caused by constant moving and stressing the cables.
• Reduces cable trip hazards in the performance space

• Limited range.
• Interference of the radio equipment or other radio microphones, though models with many frequency-synthesized switch-selectable channels are now plentiful and cost effective.
• Operation time is limited relative to battery life
• Noise or dead spots occur
• Limited number of operating microphones can be used at the same time and place.

UHF Transmitters:

• You can use it in various locations
• You can use more than 4 wireless microphones all together with multichannel systems
• You can use it in crowded VHF radio environments such as large cities and airports
• You do not have line of sight between transmitter and receiver
• You need to spend a little extra

VHF Transmitters:

• You need to use less than 5 systems at the same time
• You can perform in open radio environments, free of interference
• You do not need to have line of sight between transmitter and receiver
• You need not spend extra