Nortel BCM50, Installation And Maintenance Manual

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Chapter 9 Connecting the cables to the BCM50 system 109
BCM50 Installation and Maintenance Guide
4 Select the appropriate option for your system:
• If you are adding more auxiliary equipment, proceed to “Connecting an external music
source” or “Connecting an auxiliary ringer” on page 107 .
• If you are finished adding auxiliary equipment, proceed to “Next step” on page 112 .
Connecting an external music source
Use this procedure to connect an external music source to the BCM50 system. You can use any
customer-supplied, approved, low power device as a music source. A music source includes
equipment such as a radio with a high impedance earphone jack.
Refer to the following sections for information on connecting an external music source:
• “Music source specifications”
• “To connect the music source using the music source jack” on page 110
• “To connect the music source using the RJ-21 telephony connector” on page 110
Music source specifications
Ensure that the music source follows these guidelines:
• Nominal input impedance is 3.3 kilohms.
• Nominal sensitivity of this interface returned to digital encoded PCM is -22 dBm0 for a 0.25 V
rms input signal.
• The input is limited so that the encoded analog content at the digital interface to the network
does not exceed -12 dBm when averaged over any three-second interval.
• The maximum non-clipped input level is 1 V rms.
• The interface is protected against ringing cross.
The music source jack is located on the front of the main unit. If you use the music source jack to
connect the music source, do not connect a music source to the music source pair on the RJ-21
telephony connector.
Warning: The paging connections must not be connected to unprotected telephony
plant wiring.
Tip: Paging tips
External paging does not support talk back paging equipment unless you use an
external line port.
The BCM50 system provides paging over the telephone speakers when there is no
external paging equipment.