Merlin 3070 Service And Maintenance Manual page 169

EXTRA ALERT 1, 2, 3 jacks: Each jack accepts a moudlar line (D4CH) or equivalent and
provides a -48 volt output signal for operation of an external alert device. (See Figure
4.) These external alerting devices can be used to provide Night Service when there is
no one available to answer calls. The night service feature is programmable by assign-
ing individual lines to ring at any of the three extra-alerting devices. (Refer to the Ad-
ministering Your System At The Administration/Attendant Console section of the Ad-
ministration Manual.)
LINE
EXTRA JACK
ALERT
MODULAR LINE
CORD (D4CH)
PAGE Jack: This jack is a 4-pair modular jack for connecting an external paging system.
Pin assignments are shown in Figure 5. Pins 5(T) and 4(R) make up a balanced
600-ohm bidirectional voice pair. The remaining pins are paired and provide 3 sets of
relay contact closures for paging zone selection as shown in Table A.
Figure 5. Page Jack Locking Into Jack with Tab Opening Down
PART OF CONTROL UNIT
Figure 4. Extra Alert Jacks