5
Y1-03-0057 Rev. K
SECTION 3 – MAINTENANCE
3.1 Cleaning
External surfaces of the megaphone may be cleaned with a soft cloth, dampened in a
solution of mild household detergent. Do not immerse in water or use strong solvents. Clean
electrical contacts with cloth dampened with isopropyl alcohol.
3.2 Battery Replacement
The power supply used in the megaphone consists of six standard 1 ½ volt “AA” size
batteries. Current drain is minimal (12 mA) with the megaphone “ON”, and increases when
the user speaks into the microphone.
Battery replacement is accomplished by removing three set screws () while holding the
microphone and mouthpiece assembly (1) in place. The six cells, contained in three tubes
with two cells per tube, are immediately accessible and will drop out when the megaphone
is tilted. New batteries may be dropped into the tubes, observing polarity marking adjacent
to each tube.
Replace microphone and mouthpiece assembly (1). Align keyway and secure with the three
set screws ().
CAUTION: Observe polarity of cells carefully before replacement.
SECTION 4 – TESTING, TROUBLESHOOTING & REPAIR
Note: The megaphone consists of three major assemblies; the microphone and
mouthpiece assembly, the megaphone sub-assembly, and the horn and speaker
assembly. To locate a defect, follow the procedure outlined below:
4.1 Testing
1. Squeeze the handle. If a clicking sound is heard, the speaker is operating.
. If no sound is heard, remove the microphone and mouthpiece assembly and the
batteries. Check that both the microphone and battery contacts are clean. If not, clean
with a mild, non-abrasive cleaner such as alcohol.
3. Test amplifier and speaker assembly by replacing the microphone with a spare
microphone assembly. If no sound can be produced after microphone replacement, it
may be assumed that the amplifier or speaker assembly is defective.
4. To test the speaker, disassemble the speaker. Unplug the wires and apply 1 ½ volts
intermittently across the speaker. If no clicks are heard, the speaker is defective.
Possible faults and corrections are summarized below for ready reference.
TROUBLE
POSSIBLE CAUSE
CORRECTION
No sound from speaker
when handle is squeezed
(Step 1)
Exhausted batteries, defective
microphone,
speaker
or
amplifier assembly
Replace defective component
Sound is abnormally low or
distorted
Exhausted batteries or wrong
polarity of battery series
Check proper insertion of
batteries or replace batteries.
Speaker does not respond to
Step 4
Defective speaker
Replace speaker
