GAI-Tronics 751-901 SmartSeries Speaker Amplifier - Manual (Page 7)

Pub. 42004-659L2F
751-901 SmartSeries ® Speaker Amplifier P AGE
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f:\standard ioms - current release\42004 instr. manuals\42004-659l2f.doc
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Maintenance
Regular inspection and a good preventive maintenance program will increase the reliability of your
GAI-Tronics station. The GAI-Tronics Field Service Department can formulate a service contract suited
to your facility’s specific need for preventive maintenance.
If the equipment requires service, contact your Regional Service Center for a return authorization number
(RA#). Equipment should be shipped prepaid to GAI-Tronics with the return authorization number and a
purchase order number. If the equipment is under warranty, repairs will be made without charge. Please
include a written explanation of all defects to assist our technicians in their troubleshooting efforts. Call
800-492-1212 for help in identifying the Regional Service Center closest to you.
WARNING
Before performing any of the following preventive maintenance steps, remove
all power from the station.
1. Inspect and replace frayed or cracked wiring.
2. Secure/replace loose wires and spade terminals.
3. Remove corrosion from terminals.
There are three replaceable fuses (F1, F2, and F3) mounted on the Speaker Amp/Power Supply PCBA.
Refer to Figure 2.
 Fuse F1 protects the low voltage power supply circuits. Replace with GAI-Tronics Part No.
51801-027.
 Fuse F2 protects the current to the speaker amplifier. Replace with GAI-Tronics Part No. 51801-003.
 Fuse F3 limits the amount of current to any external device connected to J2. Replace with
GAI-Tronics Part No. 51801-024.
Adjustments
The User Adjustment Control is located beneath the GAI-Tronics nameplate on the front panel. Refer to
Figure 1. It is used to make all user adjustments normally required for installation. Loosen the two
screws on the GAI-Tronics nameplate and rotate it counterclockwise to access the adjustment hole. Make
adjustments by inserting a 1/8-inch flat blade screwdriver through the access hole and into the
potentiometer located directly behind the hole.
The User Adjustment Control potentiometer can be used to make three separate adjustments:
 Minimum speaker amplifier output level setting
 Offset amplifier level (difference between the ambient noise and the amplifier output levels)
 VLC (volume level control) adjustment (sets a preset speaker level to override the normal volume
control setting).