Samsung NX-308, Programming & Installation Manual

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The system has two music sources which may be selected by the related shunt pin, J37, on the base
board (Figure 4).
Near shunt pin J37 are two identifying marks INT and EXT:
INT position - Selection for Internal Music Source
EXT position - Selection for External Music Source.
Volume levels are adjusted by the variable resistor, RV1, near the shunt pin.
Use one-pair twisted cable, 24 AWG. The external music source can be connected through MDF.
IMPORTANT
When Music On Hold is used it may be necessary for a
Performing Rights License to be held. Consult your supplier.
External System Paging Connections
Use one-pair twisted cable, 24 AWG. The external amplifier is connected through the MDF. Refer to
the Amphenol connection table in Figure 3.
Ring and Tip terminal for external system paging has no polarity. The output impedance is 600 ohms.
If the amplifier input impedance is less than 600 ohms, the output level is reduced.
The output level of the external page circuit is fixed. Volume adjustments must be made at the
customer
’
s amplifier.
This external speaker and amplifier may be installed at the system for use by all users. External
individual paging is different from this speaker; external individual paging is set up on a keyset basis
and can be installed at each keyset.
Connecting Door Phone and Lock Control
NX - 308 system users can communicate with an optional door phone when it is installed.

Prepare a three-pair twisted cable for the door phone and lock release.

Connect the voice pair and power pair to the door phone unit. Take care when connecting the power
pair because of its polarity.
Connect the third pair to the customer-provided electronic door lock unit for control of the door lock
release mechanism. Refer to the Amphenol connection table in Figure 3.
Note: Door lock release control is to be used for low-voltage relay control only. Do not connect to
commercial AC power.
Relay maximum rating : 1 AMP, 24 VDC
When the door phone is required by the user, you should install the unit provided by Securicor
Telecoms. Any other unit will not work with the system.