PRODUCT SUPPORT MANUAL Y1-03-0014 (25-60-01) Overhaul Manual with Illustrated Parts List Rev. R EM-1A, EM-1DTM Product No. 2204, 2208 FAA PMA Approved under A3-06-1402- Portable Safety Megaphone ACR Electronics, Inc. 5757 Ravenswood Road Fort Lauderdale, Fl 33312 +1(954) 981-3333 · Fax +1 (954) 983-5087 www.acrelectronics.com Email: Info@acrelectronics.com A Chelton Group company TABLE OF CONTENTS SECTION 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 TITLE Description Technical Data Operation Cleaning Battery Replacement Testing Trouble Shooting Disassembly Inspection Check Repair Assembly Parts List PAGE 1 1 2 4 4 4 5 6 6 6 7 9 ILLUSTRATION Figure 1 Block Diagram ACR/EM-1A & EM-1D Portable Safety Megaphone Illustrated Parts List ACR/EM-1A & EM-1D Portable Safety Megaphone 3 Figure 2 8 1 Y1-03-0014 Rev. R 1.0 DESCRIPTION 1.1 The ACR/EM-1A, 1D is a battery operated solid state megaphone specifically developed for use in enclosed areas such as in the interior of an aircraft or ship cabin. It has been designed to minimize regenerative acoustic feedback that results in whistling and other oscillations of this nature. It has a 90° sound projection angle to direct the sound to persons in its immediate vicinity, as well as in the rear sections of any aircraft. The amplifier frequency band-pass has been selected to produce a crisp, clear reproduction of voice signals. The operating power level is also sufficient to provide adequate sound under high ambient noise level conditions without being over-powering. Specific attention has been given to the physical size so that it can be used effectively in a crowded environment. The EM-1A & EM-1D are the same except for installed options: OPTIONS MATRIX MODEL MANUAL GAIN ALARM ACTUATOR BATTERY MONITOR Visual EM-1A EM-1D Yes Yes Yes No Yes Yes Audible No Yes 1.2 The integrated circuit amplifier only uses a small current when turned "ON". Large currents necessary to drive the speaker are utilized only on voice peaks. This extends the life of the batteries so that several hours of operation may be expected when used normally in an intermittent manner. Batteries should be replaced periodically as recommended by the manufacturer. (See section 5.0) A simplified block diagram of the megaphone is shown in Figure 1. 2.0 TECHNICAL DATA Dimensions Weight Materials 5.5" max diameter bell, 11.5" max long 2.3 lbs., including batteries Horn, handle ­ Anodized Aluminum Housing ­ Aluminum Neck strap at top of unit Attachment 2 Y1-03-0014 Rev. R Gain Control* Amplifier Speaker Thumb operated Integrated circuit, 2 watts power output Re-entrant horn and driver type; input power five (5) watts; 90° dispersion angle High Sensitivity Six (6) standard 1½ volt "AA" cells 25 milliamps static current 550 milliamps maximum current 500 to 3500 Hz Warbling tone 500 ­ 1200 Hz Plug pin, retained by nylon cord Visual Flashing Green LED* Acoustical Beep* Microphone Batteries Power Drain Frequency Response Anti-Removal Alarm* Alarm Actuator* Battery Test Circuits *Optional feature (see options matrix) 3.0 OPERATION 3.1 A siren, incorporated into the megaphone, is automatically activated by unplugging the alarm plug pin.* Note: A long lanyard with an alarm plug pin is supplied with the megaphone for use as an anti-theft alarm (optional). 3.2 Squeezing the handle automatically stops the siren, and the megaphone is ready for use. Re-insert the alarm pin so that alarm will not be reactivated when pressure on the handle is removed. Hold the megaphone in one hand. Place mouth almost in contact with the microphone mouthpiece at the rear of the assembly. Squeeze the handle, which will flex slightly, turning the megaphone "ON" and speak slowly with loud, crisp, clear tones. Megaphones without the optional gain control knob are preset to a standard level via control under access hole plug. 3.3 3 Y1-03-0014 Rev. R 3.4 Adjust the volume control knob to a suitable sound level. The volume control may be adjusted with the thumb of the same hand holding the megaphone.* When not in use, carry the megaphone by the neck strap, attached to top of unit. 3.5 SPEAKER ASSEMBLY VISUAL BATTERY CHECK LED VOLUME CONTROL MICROPHONE ASSEMBLY + + AUDIO AMPLIFIER SIREN CIRCUIT & BATTERY MONITOR MEGAPHONE SUB-ASSEMBLY N.O. * ALARM PLUG PIN N.C. HANDLE SWITCH + BATTERY PACK (6 x AA) - FIGURE 1 BLOCK DIAGRAM ACR/EM-1A, EM-1D PORTABLE SAFETY MEGAPHONE 3.6 Battery Monitor Two types of battery monitor are available on the EM-1 series megaphones.* Visual - when megaphone is activated by squeezing the handle, a green LED indication means the remaining battery capacity is greater than 50% of initial capacity. If the green LED is out, replace batteries. 4 Y1-03-0014 Rev. R Audible - when megaphone is activated by squeezing the handle, a chirp heard in the speaker means the remaining battery capacity is greater than 50% of initial capacity. If beep is not present, replace battery. 4.0 CLEANING 4.1 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. 5.0 BATTERY REPLACEMENT (see Figure 2) 5.1 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 (3) while holding the microphone and mouthpiece assembly (2) in place. The six battery 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 (2). Align keyway and secure with the three set screws (3). CAUTION: Observe polarity of cells carefully before replacement. 5.2 5.3 6.0 TESTING 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: 6.1 6.2 Squeeze the handle. If a clicking sound is heard, the speaker is operating. Remove the pin that activates the siren. If the alarm is of normal amplitude and sound character, the amplifier and siren circuitry are functioning properly. If the amplification is low, check the batteries and 5 Y1-03-0014 Rev. R then the amplifier. If the sound character is abnormal, check the batteries and then the siren circuitry.* 6.3 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. 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. To test the speaker, disassemble the speaker. Disconnect one wire and apply 1 ½ volts intermittently across the speaker. If no clicks are heard, the speaker is defective. * Optional Feature (see options Matrix) 6.4 6.5 7.0 7.1 TROUBLESHOOTING Testing procedure for locating defects is given in paragraph 6.0. Possible faults and corrections are summarized below for ready reference. POSSIBLE CAUSE Exhausted batteries, defective microphone, speaker or amplifier assembly Exhausted batteries, defective siren circuitry or defective amplifier Exhausted batteries or wrong polarity of battery series Defective speaker TROUBLE No sound from speaker when handle is squeezed (Step 6.1) CORRECTION Replace defective component No siren when alarm pin is pulled (Step 6.2)* Replace defective component Sound is abnormally low or distorted Speaker does not respond to Step 6.5 Check proper insertion of batteries or replace batteries. Replace speaker *Optional Feature (see options Matrix) 6 Y1-03-0014 Rev. R 8.0 DISASSEMBLY (see Figure 2) 8.1 Megaphone should be disassembled for repair or replacement of components only. 8.1.1 Remove microphone and mouthpiece assembly (2) by removing the three set screws (3). Remove battery cells (4) from the three tubes by tilting megaphone to allow cells to drop out into the hand. Unplug alarm plug pin (5) from side of housing.* Remove volume control knob (6) (pulls off). Remove the three oval head screws (11) at periphery of the speaker end of the housing (15). Extract speaker (7) and megaphone assembly (10) by firstly turning horn (18) clockwise 45°. Pull entire assembly gently until it stops. Turn horn (18) counterclockwise 45°, then pull the entire assembly out. Separate Speaker Assembly (7) and Megaphone Subassembly (10) by firstly unplugging the speaker wires from the "out" header. Remove hex screw that holds the assemblies together. Disassembly in steps 8.1.1 through 8.1.7 above is sufficient to examine the megaphone for faults and testing. Further disassembly is not recommended. 8.1.2 8.1.3 8.1.4 8.1.5 8.1.6 8.1.7 8.1.8 9.0 INSPECTION / CHECK 9.1 Inspect unit for any evidence of damaged parts, loose mountings or broken leads and dirty electrical contacts. 10.0 REPAIR 10.1 The megaphone consists of three major sub-assemblies; the Microphone and Mouthpiece Assembly, the Megaphone Sub-Assembly, and the Horn and Speaker Assembly. Repairs are restricted to the replacement of these defective sub-assemblies or the batteries and lanyard assemblies. 11.0 ASSEMBLY 7 Y1-03-0014 Rev. R 11.1 Assembly of the megaphone is in reverse order of disassembly. Follow these instructions: 11.1.1 Attach Horn (18) and Speaker Assembly (7) to Megaphone Subassembly (10). Ensure alignment with location pins. Pass speaker wires through the provided slot. 11.1.2 Plug speaker connector into the "out" header on PCB. 11.1.3 Push entire assembly gently into the housing (15), until it stops. Turn clockwise 45° and push all the way in. Turn counterclockwise 45° and align holes. 11.1.4 Secure with screws (11). 11.1.5 Replace volume control knob (6) on volume control shaft. 11.1.6 Plug the alarm plug (5) attached to lanyard into jack in the side of the case near volume control.* 11.1.7 Replace the six batteries (4) in three tubes at microphone end of megaphone case. CAUTION: Observe polarity of batteries during installation procedure (see instructions at battery tube openings of the megaphone). 11.1.8 Replace microphone and mouthpiece assembly (2). Align keyway, and secure with the three setscrews (3). 11.1.9 Steps 11.1.1 through 11.1.8 complete the assembly of the megaphone. After assembly, test unit in accordance with Paragraph 6.0, Testing. 8 Y1-03-0014 Rev. R FIGURE 2 ACR / EM-1A, EM-1D PORTABLE SAFETY MEGAPHONE ILLUSTRATED PARTS LIST 8 12.0 PARTS LIST 12.1 Replaceable parts are illustrated in Figure 2, and listed below in the table. Part numbers shown in the "Part Number" column may be ordered from ACR unless another manufacturer's name is given in parenthesis in the "Description" column., In this case, replacement parts can be obtained directly from the original manufacturer. Standard parts (MS-, AN-, etc.) and commercially available hardware (`Commercial') should be obtained from commercial sources. NOMENCLATURE ORDER SPARE PARTS EM-1A S/N < 9000 EM-1A S/N 9000 #2204 9211 9416 Commercial 9022.1 9418 N/A N/A 9420 Commercial 9423 9233 9164 A1-18-1149 9161 A1-17-0809 ITEM QTY EM-1D ALL S/N #2208 9211 9416 Commercial 9022.1 9418 N/A N/A 9422 Commercial 9423 9233 N/A A1-18-1151-1 N/A A1-17-0809 1 2 3 4 6 7 8 9 10 11 12 13 & 17 14 15 16 18 1 1 1 6 1 1 3 2 1 3 1 1 1 1 1 1 Megaphone, Safety Microphone & Mouthpiece Assy Socket Setscrew Kit Battery AA Alkaline Knob, control Speaker Assembly Screw, Self tap (#4 x ¾) Wire leads speaker (#26AWG) Megaphone Subassy Screw Machine (#4-40 x 3/8) Handle Kit Strap Assembly Kit Lanyard Assembly, Anti theft Housing Megaphone Lanyard Assembly, Siren Horn, Megaphone Obsolete 9211 9416 Commercial 9022 9417 (upgrade kit) Commercial Commercial 9417 (upgrade kit) Commercial 9423 9233 9164 A1-18-1149 9161 A1-17-0809 S/N 9000 are date coded 4/99 + 9 ...