Trunk Mount Amplifier
(120-1975/A)           Care and Maintenance           Faxback Doc. # 17490

CARING FOR YOUR AMPLIFIER

Your Optimus 4-Channel 150-Watt Trunk Mount Amplifier is an example of
superior design and craftsmanship.  The following suggestions will help you
care for your amplifier so you can enjoy it for years.

    Keep the amplifier dry.  If it gets wet, wipe it dry immediately.
    Liquids can contain minerals that corrode electronic circuits.

    Use and store the amplifier only in normal temperature environments.
    Temperature extremes can shorten the life of electronic devices and
    distort or melt plastic parts.

    Handle the amplifier gently and carefully.  Dropping it can damage
    circuit boards and cases and can cause the amplifier to work
    improperly.

    Keep the amplifier away from dust and dirt, which can cause premature
    wear of parts.

    Wipe the amplifier with a damp cloth occasionally to keep it looking 
    new.  Do not use harsh chemicals, cleaning solvents, or strong 
    detergents to clean your amplifier.

Modifying or tampering with amplifier's internal components can cause a
malfunction and invalidate your amplifier's warranty.  If your amplifier
is not performing as it should. take it to your local Radio Shack store for
assistance.

CORRECTING AN OVERLOAD

The amplifier's overload protection circuit automatically shuts down the
amplifier and the yellow PROTECTION indicator lights.

Follow these steps if the amplifier automatically shuts down.

1.  Turn off your sound system.

2.  Disconnect your vehicle battery's negative (-) terminal and the stereo
    system's wiring harnesses.

3.  Find the problem, and try the solution listed in the following chart.

Problem:                                Solution:

The amplifier overheats.                Increase the amount of space around
                                        the cooling fins to improve the
                                        airflow and cooling.
                                        Move the amplifier farther away 
                                        from a heater vent.

The speaker wires are                   Recheck all speaker wire connections.
shorted.

The ground wire is open                 Recheck ground wire connections.

The existing speakers have              Replace the speakers with 4-Ohm (or
an impedance less than 4                greater) speakers.
Ohms.

4.  Let the amplifier cool down before you restart it.

REPLACING A FUSE

If the amplifier shuts down but the yellow PROTECTION indicator does not
light, you might need to replace either the 20-Amp tube-type fuse (Cat. No.
270-1074) in the fuse holder of the red power wire or the blade-type 
automotive fuse (Cat. No. 270-1083) on the back panel, or both.

Follow these steps to check a fuse and replace it, if necessary.

1.  Turn off your sound system.

2.  Disconnect your vehicle battery's negative (-) terminal and the stereo
    system's wiring harnesses.

3.  To remove the red power wire's fuse, grasp the two ends of the fuse 
    holder, push them in and twist them counterclockwise, then pull the 
    ends apart.

    To remove the back panel's automotive fuse, grasp the fuse's plastic 
    ends and pull it out.

4.  Remove and replace the fuse.

    Caution:  Do not use a fuse other than the specified fuse.  Doing so 
    might damage your amplifier.

5.  Let the amplifier cool down before you restart it.


(CS/all-10/23/95)