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MUSIC-ON-HOLD-45 1 A OR B KTU
6. 1 9
The same music source used for background
music can be multipled at the 33A voice
coupler to furnish music-on-hold. The 451A or B
KTU is required to furnish an output to the seven
CO/PBX lines.
When the lines are in a talk
condition, the output of the 451A or B KTU is
shorted by contacts in the associated line circuit.
When placed on hold, the output is impressed on
the ring side of the CO/PBX line and can be heard
by the held party.
ISS 3, SECTION 5 1 8-450- 1 00
6.20
Tables AG, AH, AI, AJ, and Fig. 72 are
provided as an aid in the maintenance of
background music and music-on-hold circuits.
POWER DISTRIBUTION
6.2 1
Refer to Fig. 73 for power distribution circuit
information.
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