Control Signals - Philips SOPHO SuperVisor 25 Engineer's Manual

6.6.3.

Control Signals

The control signals on the auxiliary connector are used to control up to four announcers and/
or a recorder. The recorder can be used to record voice of the handset/headset. (This voice
is presented at the audio-out connector.)
The control signals are presented as open collector in relation to the signal 'Ground'. The
following signals are available:
- Announcer 0;
- Announcer 1;
- Trigger announcer;
- Recorder;
- Ground.
Announcer 0 and 1
Announcer 0 and 1 represent a binary code to select up to four announcers.
If the collector conducts (on state) it means that the signal is active. In this case the signal level
will be ground level.
If the collector is 'open' (off state) it means that the signal is inactive. In this case the signal level
is floating.
Trigger Announcer
By means of a trigger pulse of 250 ms the announcement is started.
If the collector conducts (signal level = ground level) it means 'trigger pulse active'.
If the collector is open (signal level = floating) it means 'trigger pulse not active'.
Recorder
The recorder signal activates a recorder in case of an incoming call. Note that the voice path
of the recorder must be connected to the 'audio out' cinch connector.
If the collector conducts (signal level = ground level), it indicates that the recorder must be
active (recording).
If the collector is open (signal level = floating) it means 'no recording'.
Ground
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