Clear-Com AB-120 - Manual (Page 25)

Clear-Com Communication Systems
AB-120 Announcer Console Instruction Manual
4 - 1
GLOSSARY
Some of the terms used when discussing critical communications for
television or theatre may be new to you as they are unique to intercom
applications. Although many of the terms are common to other audio
applications, to be certain you understand their meanings we offer the
following definitions:
All Call: Ability to push one button from the main station and talk to all
channels at once on a multiple channel system.
Ambient Noise: Those background sounds that are not part of the
specific communication but are picked up by the microphone.
Selection of a good “noise-cancelling” mic will reduce ambient noise.
Beltpack: A portable electronics package worn on the belt or mounted
on a wall or other convenient location. Interconnects to system with
mic cable and is powered by a central power supply or main station.
Bridging, High Impedance (hi-Z): A method of connecting to an
audio line (such as Clear-Com) without loading or taking appreciable
power from that line. Simply stated, as you add more and more
stations to the line, the volume remains constant.
Call Signaling: This feature is included with the majority of
Clear-Com products. It is a visual indicator on a station (red light) used
to attract the attention of an operator who has removed the headset.
Channel vs. Station: A channel is the line that connects parties
together within a party line - it is a two-way talk path. For example, if
you have six people who need to hear one director, you have a
seven-station single-channel need. If the same director needs to speak
privately to any one of the six, add a second channel. You now have a
seven-station, two-channel system.
Closed-Circuit: Any intercom which is connected via cable (also
called hard-wired). The other type of intercom is wireless and is also
available from Clear-Com. However, if you want privacy and versatility,
you probably want a closed-circuit system or a combination of both.
Crosstalk: Leakage of audio transmissions from one channel to
another.
Dry Pair: A telephone term is used to describe a pair of wires (two
conductors) that carry audio but no voltage. Contrast this with a wet
pair that carries both audio and voltage.
Duplex: Duplex refers to bi-directional communications. Normal
communication between individuals talking face to face is “full duplex”;
in other words, you can talk and listen simultaneously. The other
alternative is “half-duplex,” such as a push-to-talk situation where one
4