MPA-101 100-Watt PA Amplifier
(320-2039)                      Troubleshooting       Faxback Doc. # 14627

If you have problems with the amplifier, use the following checklist to 
solve the problem.  If these suggestions do not solve the problem, take
the amplifier to your local Radio Shack store for assistance.

    Be sure the sound source and speaker connections are correct.

    Be sure there are no short circuits in the speaker wiring.

    Be sure you have provided adequate ventilation.

    Be sure you have correctly calculated the speaker impedance.

    Be sure all cables and microphones are functional.

    Be sure the speaker wire is a large enough gauge:  18-gauge for wire 
    lengths up to 25 feet and 16-gauge wire for lengths over 25 feet.  For
    the best results, use the shortest length of speaker wire possible.

    If you hear feedback, use a PA Amplifier with a feedback filter and
    adjust the FEEDBACK FILTER.  This should decrease the feedback by up
    to 12 dB. If necessary, reposition your microphones or speakers.  If
    this does not eliminate the feedback, a frequency equalizer can help
    decrease the feedback even more.

    If the system suddenly stops working, check the PROTECTION indicator. 
    If it is lighted, the system overheated and the built-in protection
    circuit temporarily interrupted the power.  Press POWER to turn off
    the amplifier.  Let the amplifier cool for about 15 minutes and
    correct whatever caused the overload.  Then press POWER to turn on the
    power.

    If the amplifier does not work at all, check the fuse (located on the
    back panel).  If is blown, replace it with an identical 3-amp,
    250-volt fuse.


(SP/ir-04/08/96)