PAGE 9 of 28Talkback to a given zone is accomplished by plugging the provided handheldmicrophone into the AUX Mic Jack[30] on the DG-MA front panel and holding downthe respective Zone Selector Switch[1]. To talk to all zones at once, press the AllCall Pushbutton Switch[33]. The volume of the talkback audio heard at the zone isset by the Talkback Level Control [31] on the front of the DG-MA.INSTALLATION-Mechanical:The DG-25III and DG-MA units mount to a 19” wide equipment rack. They should belocated away from extreme dampness or heat to ensure long life and reducemaintenance requirements. Adequate space should be provided around the unitswhen placed inside the rack to prevent heat build-up due to poor air circulation. Theair must be vented out of the cabinet. The fan's filter filament should be taken out ofthe guard and cleaned with warm water after 3 months and replaced every sixmonths. The filter filament should be cleaned more often when subjected to dust ordirt. Additional filter filaments can be obtained from Louroe Electronics (part #28-0074-1.)OPERATION (cont.):INSTALLATION AND OPERATING INSTRUCTIONSLOUROE ELECTRONICS 6 9 5 5 VA L J E A N AVENUE, VAN NUYS, CA 91406 TEL (818) 994-6498 FAX 994-6458website: www.louroe.com e-mail: sales@louroe.com(818)®dg_25_inst_1/12