Figure 5.9 TW and Matrix Signal Flows
User Station
TW Signal Flow
“Generic”
Microphone
Sidetone
Speaker
Bidirectional
Audio to
Other Stations
+
+
User Station
Matrix Signal Flow
“Generic”
Microphone
Volume
Balanced Audio
From Matrix
Balanced
Audio
To Matrix
Speaker
BASIC SIGNAL FLOW DIFFERENCES
BETWEEN TW & MATRIX INTERCOMS
In a wireless intercom system, the communication may be full duplex, with the two sides of the conversation carried on two separate frequencies. This is the case with all the Telex® RadioCom™ products. In this way, the signal format is essentially the same as the matrix intercom system shown in Figure 5.9.
In some wireless communications systems (two-way radios for example), both talk and listen may share a single frequency, in which case the communication must be half duplex, with the users taking turns between talking and listening. A good example of such a system is low cost walkie-talkies, wherein the speaker you hear audio from doubles as the microphone you speak into when you press the transmit button. In the following discussion, we do not concern ourselves with that variety of two-way radio systems because those systems are rarely encountered in installations with intercom systems. For more detailed information, refer to the chapters on wireless intercom.
Interconnecting Matrix, PL, and Wireless Systems
As discussed earlier, the signal format for ADAM™, ADAM™-CSand Zeus™ Matrices is the same as used in the Telex® RadioCom™ line of wireless intercoms. This makes interfacing between the two systems very easy, and in fact, Telex provides connectors specifically for this on the RadioCom™ products. To make the two systems work together, you simply connect two audio lines.
78 H a n d b o o k o f I n t e r c o m S y s t e m s E n g i n e e r i n g
