Clear-Com AB-120 - Manual (Page 19)

Clear-Com Communication Systems
AB-120 Announcer Console Instruction Manual
1 - 1 3
Figure 1-8: AB-120 Connected to a TW Party-Line System
TW Party-Line Systems (RTS)
A TW party-line system is described as follows:
IFB
IFB is provided by a two channel interrupt and non-interrupt system.
INTERCOM
Talkback is provided from one or two channels of a TW party-line
system Channel ‘1’ is the producer channel. Any announcer pressing
the talkback button would speak into this channel. Any or all of the
announcers may talk at any time as they are summed on the party-line
channel.
Set the channel switch on the rear panel to ‘1’. If the second power
option is installed, any announcer pressing the mute button can talk on
that channel.
POWER
Power for the AB-120 is derived from the intercom line, an external DC
supply or optionally from the IFB.