AT&T System 75 Wiring Diagram page 293

CHAPTER 5. AUXILIARY EQUIPMENT INSTALLATION
For 110-type hardware, install a yellow (auxiliary) label on the
5.
110-type terminal block. For 66-type hardware, write the lead
designations on the 66-type connecting block with a felt-tipped pen.
6. Remove the cover from the 36A voice coupler, and install the voice
coupler.
7. At the 36A voice coupler;
Make connections to the 110-type wiring blocks on the
ED-1E443-10 intra-connection panel (Figure 5-10).
Connect a 2012D transformer to terminals AC and ACG.
Install the cover.
Install music source per the manufacturer's instructions.
8.
9. Connect a 2-pair line cord (modular plug at one end) from the
information outlet to the music source (Figure 5-10).
10. Install patch cord/jumper wires at the cross-connect field.
11. Plug the 2012D transformer into a 117-volt ac receptacle not under
control of a wall switch.
12. Administer per AT&T System 75 and System 75 XE—Implementation
( 5 5 5 - 2 0 0 - 6 5 1 ) a n d AT&T System 75 and System 75
XE—Administration (555-200-500).
Installing Loudspeaker Paging With Background Music
Requirements
Figures 5-11 and 5-12 show the additional connections required when
loudspeaker paging is installed with background music. Refer to the
installation procedures for installing loudspeaker paging (278A adapter
or 89A control unit) and music-on-hold.
Installation Using 278A Adapter
Connect the 278A adapter as follows:
1 . On the 278A adapter (Figure 5-11), connect the music source to
terminals M1 and M2.
5-20