User Manual For Amron International Diving Supply, Inc.

User Manual For Amron International Diving Supply, Inc. Model 2840R/24/XX Series 4- Diver Rack Mount Communicator S/N This manual and the information contained herein are provided for use as an operation and maintenance guide. No license or rights to manufacture, reproduce, or sell either the manual or articles described herein are given. Amron International Diving Supply, Inc. reserves the right to change specifications without notice. Amron International Diving Supply, Inc 1380 Aspen Way Vista, California, 92081, U.S.A Phone (760) 208-6500 Fax (760) 599-3857 Email: Sales@amronintl.com Website: www.amronintl.com Copyright 2011 Amron International, Inc. Revised May 2011

TABLE OF CONTENTS Specifications 1 General Information 2 General Information...2.1 Front Panel Controls, Drawing 2840R/24-C601...2.2 Option Controls, Drawing 28XXR-OPT-B601...2.3 Options 3 Warranty and Service Policy 4 Limited Warranty...4.1 Service Policy...4.2 Controls & Connections 5 Controls and Connections...5.1 Tender Controls...5.2 Tender Connections...5.3 Diver Controls...5.4 Diver Connections...5.5 Other Connections...5.6 Options...5.7 Drawing, 2-Wire Connections...5.8 Drawing, Simulcom 4-Wire Connections...5.9 Drawing, Operator Connections, P.T.T. Microphone...5.10 Drawing, Operator Connections, Headset...5.11 Installation & Operation 6 Operation...6.1 Power ON...6.2 Modes of Operation...6.3 2-Wire Operation...6.4 Other Diver Controls...6.5 Simulcom (4-Wire) Operation...6.6 Other Tender Controls...6.7 Simulcom What, Why and How?...6.8 Maintenance...6.9 I

TABLE OF CONTENTS Theory of Operation 7 Theory of Operation...7.1 Amplifier Card 2832-204-03...7.2 Audio Volume Controls...7.3 Battery Charger Card, 2324-202...7.4 Option /26DSP2 Helium Unscrambler...7.5 Functional Block Diagram Model 2840R...7.6 Maintenance & Trouble Shooting 8 Diver Radio Field Check Procedures...8.1 Quick Simulcom Check...8.2 Comprehensive 2-Wire and Simulcom Check...8.3 Problems and Their Possible Causes...8.4 Drawings & Schematics 9 General Information...9.1 Schematic, 2840R/24...9.2 Schematic, Option 4002...9.3 Schematic, 2823-6002...9.4 Schematic, 2830-200...9.5 Parts Identifier, Front Panel Model 2840R/24...9.6 Parts Identifier, Options...9.7 Parts List 10 General Information...10.1 AMCOM IV Rack Mount Model 2840R/24...10.2 AMCOM IV Rack Mount, Unscrambler 2840R/24/26DSP2...10.3 AMCOM IV Model - 4002 Option...10.4 Sub Assembly 2840R-400 Front Panel Assembly...10.5 Sub Assembly 2840R/26-400M Front Panel Assembly...10.6 Sub Assembly 2840R-4002-400M Front Panel Assembly...10.7 2825R-500M Chassis Assembly...10.8 Sub Assembly 2823-6002 Internal Charger Assembly...10.9 2324-202 Power Supply Card Assembly...10.10 28XXA-FS Spares Kit for 2840R/24...10.11 Optional-PC Card Assembly Spares...10.12 II

SPECIFICATIONS SPECIFICATIONS 1.1 Electrical Input Impedance (Each Input)...250 Ohms Frequency Response...300-10000 Hz Common Mode Rejection...40 db Minimum Current Drain Maximum Full Volume...3 Amps Minimum Quiescent...0.370 Amps Output Impedance...less than 1 Ohm Power Supply Voltage... 12 VDC Nominal (9 Volts Minimum - 14 Volts Maximum) Sensitivity (Input)...0.5 mv Output Power (RMS @ 4 Ohm Load, 12 VDC)...20 Watts Audio AC Power....120/220 Volts AC 50/60 Hz Internal Power...12 Volts DC (2 ea. 6 Volt) Re-chargeable Gel Cell Battery Battery Life...10 Hours Mechanical Panel...Anodized Brushed Aluminum Enclosure... Black Anodized Aluminum Dimensions Length... 12.5 in. (31.75 cm) Width... 19.0 in. (48.25 cm) Height... 6.97 in. (17.7 cm) Weight with Batteries... 20.5 lb. (9.2 kg) 1

GENERAL INFORMATION GENERAL INFORMATION 2.1 The AMCOM IV Rack Mount is a full feature hard wire, four diver communicator system. The AMCOM IV is designed for system integration; the enclosure can be mounted in a standard electronic relay rack. All inputs/outputs are available on the rear of the unit for a clean and neat installation while maintaining front panel connectors for ad-hoc situations. All configurations of the AMCOM IV operate from AC power (100 to 240 Volts AC, 50/60 Hz), with a built in battery backup. Batteries are continuously charged when the system is operating from the line voltage, in the event of loss of AC power, the unit continues to operate, without user intervention, from the batteries. The AMCOM IV delivers 20 Watt Peak-Effective-Power to the tender and to each diver for clear communications. It has the capability to operate in 2-wire and/or 4-wire (Simulcom) mode. Operations can be mixed with divers using 2-wire requiring the use of the push-to-talk switch while 4-wire provides a hands-free, telephone like communication experience. All tender and diver input are isolation and have individual controls. The diver channel has the ability to operate with either dynamic or pre-amplified microphone in either 2-wire or 4-wire mode. Each channel independently automatically detects the type of microphone used and adjusts the system operating gain (volume) as necessary. The AMCOM IV is offered in a base configuration as well as with several options. Each option is designated by a suffix. Suffix designations are described as follows: /26DSP2 /28FDW Helium Speech Unscrambler Wireless Tender, 4-wire mode (full duplex) -4002 Chamber Lock Call Indicator & Annunciator The /26DSP2 Helium Speech Unscrambler Provides for correction of the effects of breathing Helium gas mixtures. Correction range is from the surface to 2000 FSW. Two modes of operation are provided: one for shallow depths and another for deeper depths. The /28FDW Wireless tender, 4-wire mode (full duplex) Adds the wireless tender option to the base unit. Permits the tender to carry on conversations with the divers while moving around without having to be connected to the unit with wires. Range is dependent upon surround structures, up to ¼ mile under ideal conditions. Can only be used in the Simulcom mode of operation. The -4002 Chamber Lock Call Indicator & Annunciator The call indicator has three LED s on the front panel, which are activated by a switch located in the chamber at the same time, the call annunciator sounds an audio signal alerting the operator that someone is trying to contact them. 2

GENERAL INFORMATION DRAWING, FRONT PANEL CONTROLS MODEL 2840R/24 2.2 3

GENERAL INFORMATION DRAWING FRONT PANEL OPTIONS /26,-4002 2.3 4

OPTIONS OPTIONS 3.1 Model -4002 Chamber Lock Call Indicator with annunciator. Model /26DSP2 Helium Speech Unscrambler, dual mode, surface to 2000 FSW can not be combined with the Wireless Tender or Chamber Lock options. Model /28FDW Wireless Tender option Simulcom (full duplex) Includes tender heavy duty headset. Simulcom (4-wire) operation only. Model 2829-01 Wireless Tender Headset Full Duplex Heavy Duty for use with /28FDW Wireless Tender Option. Model 2821-28 AMRON headset extension (remote walk and talk), with push-to-talk belt module (2-wire operation only), jacks for headset, 25 feet 1/4" O.D.cable. (Use with Model 2460-28 or 2401-28 headsets). Model 2822-28 Headset Extension (Simulcom 4-wire), belt module with 25 feet 1/4" O.D.cable. (Use with model 2460-28 or 2401-28 headsets). Model 2401-28 Deluxe headset with boom microphone, dual banana plugs. Model 2460-28 Headset with boom microphone, dual banana plugs. Model 2405-28 Hand held push-to-talk noise canceling microphone. 5

WARRANTY LIMITED WARRANTY 4.1 AMRON INTERNATIONAL DIVING SUPPLY, INC. warrants that its products are free from defects in material and workmanship under normal use and service, for a period of 90 days from date of shipment as described in AMRON INTERNATIONAL DIVING SUPPLY, Inc. literature covering this product. Amron s obligation under this warranty is limited to the repair of or replacement, at AMRON S option, of defective material. This warranty shall not cover defects which are the result of misuse, negligence, accident, repair or alterations. SERVICE POLICY 4.2 AMRON INTERNATIONAL encourages owners of equipment to call (760) 208-6500 for assistance if problems are encountered. Every effort will be made to assist in solving your problem. Equipment which must be returned to the factory for repairs should be safely packaged, insured, and shipped prepaid to: Be sure to include the following information: Amron International, Inc. 1380 Aspen Way Vista, Ca. 92081 Your Name Your Company Name Shipping Address Phone Number Contact Name A short description of the problem is most helpful. Valid in warranty repairs will be made at no charge. Out of warranty repairs will be handled in the same fashion, except you will be advised of the estimated repair charges before proceeding with repairs. 6

CONTROLS & CONNECTIONS CONTROLS AND CONNECTIONS 5.1 Before using the AMCOM IV diver communications system, you should familiarize yourself with the operating controls and connections. Improper use of controls and connections will deprive the user of the full benefits of this communication system. We also recommend reading the "SIMULCOM" description located in the Operation Section of this manual, for an explanation of advantages and "How to Implement" your Amcom IV Communications System. TENDER CONTROLS 5.2 POWER SWITCH - Applies power to the unit from internal batteries or from external source. SPEAKER SWITCH - Turns panel speaker and microphone on/off. To prevent acoustic feedback, it may be necessary to turn speaker off when the tender uses a headset. PUSH TO TALK ALL DIVERS SWITCH This switch allows tender to talk to all divers in 2-wire mode. (No push to talk required when operating in Simulcom (4-wire) mode). In Simulcom mode this switch allows the tender to interrupt divers with a priority message; all divers will be listening. VOLUME - DIVERS TO TENDER - Controls panel speaker and/or tender headset volume. Use as master volume control, clockwise increases volume. VOLUME - TENDER TO DIVERS Controls the tender microphone volume. Use as a master volume control, clockwise rotation increases the volume to all divers. BATTERY CONDITION INDICATOR Steady GREEN light indicates battery voltage level is good. Blinking GREEN light indicates battery voltage is approaching a low level. Steady RED light indicates battery voltage is below the level necessary to guaranty proper operation. WARNING: When Battery Condition indicator is steady RED light, communication will stop. PANEL SPEAKER - Acoustic horn speaker, it operates when Speaker Switch is ON. PANEL MIC A panel mount acoustic microphone, it operates when Speaker Switch is ON. AC POWER A LED that is illuminated when the system is connected to AC power. TENDER CONNECTIONS 5.3 HEADSET JACK (output/input) - Is a dual banana jack (color coded black) connection for headset earphones, also it is available on the rear panel. It functions as an earphone (output) and a microphone (input) when PTT switches depressed. In 2-wire mode of operation both headset microphone and earphones are plugged into this jack, conversation (up-link & down-link) are switched automatically when push to talk switch is actuated. In Simulcom mode this jack is earphone only, both up-link & downlink conversations are heard. 7

CONTROLS & CONNECTIONS MICROPHONE JACK (input) - Is a dual banana jack (color coded red) connection for the headset microphone, also it is available on the rear panel. Tender microphone volume control adjusts the sensitivity of the input. PUSH TO TALK JACK- Is a dual banana jack (color coded yellow) connection for remote keying of push to talk; also it is available on the rear panel. DIVER CONTROLS 5.4 VOLUME DIVER TO TENDER (Diver 1, 2, 3 & 4) - Controls amplification of diver s microphone signal, therefore control diver s volume to tender and to all divers. Each diver circuit has its own volume control. VOLUME TENDER TO DIVER (Diver 1, 2, 3 & 4) - Controls diver s earphone signal, therefore control diver s hearing volume from tender and to all divers. Each diver circuit has its own volume control. PUSH TO TALK DIVER 1 In the two wire mode, the PTT DV-1 momentary switch which allows the tender to talk to diver 1 only. PUSH TO TALK DIVER 2 In the two wire mode, the PTT DV-2 momentary switch which allows the tender to talk to diver 2 only. PUSH TO TALK DIVER 3 In the two wire mode, the PTT DV-3 momentary switch which allows the tender to talk to diver 3 only. PUSH TO TALK DIVER 4 In the two wire mode, the PTT DV-4 momentary switch which allows the tender to talk to diver 4 only. DIVER 1 TO DIVER 2, 3 & 3 - In the two wire mode, the DV-1 TO 2, 3 & 4 momentary switch allows diver 1 to talk to divers 2, 3 & 4, while the switch is depressed. DIVER 2 TO DIVER 1, 3 & 4 - In the two wire mode, DV-2 TO 1, 3 & 4 momentary switch allows diver 2 to talk to divers 1, 3 & 4, while the switch is depressed. DIVER 3 TO DIVER 1, 2 & 4 - In the two wire mode, DV-3 TO 1, 2 & 4 momentary switch allows diver 3 to talk to divers 1, 2 & 4, while the switch is depressed. DIVER 4 TO DIVER 1, 2 & 3 - In the two wire mode, DV-4 TO 1, 2 & 4 momentary switch allows diver 4 to talk to divers 1, 2 & 3, while the switch is depressed. 8

CONTROLS & CONNECTIONS DIVER CONNECTIONS 5.5 MICROPHONE (input/output) (Applies to Diver 1, 2, 3 & 4) - This front panel connector is a dual 5-Way Binding Post Jack (color coded red). Also it is available on the rear panel, which would be the preferred connection point for permanent installations. It functions as a microphone (input) and as an earphone (output) when PTT switch is depressed (used in both 2 & 4-wire mode). In the 2-wire mode of operation, both diver microphone and earphone banana plugs are stacked into the umbilical microphone jack (red binding posts). Conversation (up-link & down-link) is automatically switched when push to talk switch is actuated. In Simulcom (4-wire) mode, only the diver microphone banana plug is connected into the umbilical microphone jack. EARPHONE Jack (output) 4 Wire, (Diver 1, 2, 3 & 4) - This front panel connector is dual 5- Way Binding Post Jack (color coded black). Also it is available on the rear panel, which would be the preferred connection point for permanent installations. It is the connection point for the diver s earphone when operating in the Simulcom mode (4-wire). OTHER CONNECTIONS 5.6 TAPE RECORDER provides an isolated output, of both diver and tender conversations (balanced), suitable to drive a tape recorder or audio input of a VCR. This feature allows recording of conversations between diver and tender. It is located on rear panel. AC POWER AC power cord can be plugged to rear panel. Communicator operates with both 110V and 220V (50 or 60 Hz). There is an internal power supply card that detects the supplied AC voltage either 110V or 220V and automatically switches the internal relays to the proper voltage. There is no manual switch to select the supplied voltage as it switches automatically inside the power supply. Also this internal power supply regulates the voltage to 14 VDC to supply the amplifier card and charges the internal batteries at the same time. MS Connector Mounted on the rear panel, this connector provides connections to Diver and Tender inputs and outputs. This eliminates the need to run wires from the front panel. Mating connector is P/N MS-3106A-28-16P MS Connector Pin Out Identifications Pin Number Function A & B Diver 1 Microphone G & E Diver 1 Earphone L & M Diver 2 Microphone F & H Diver 2 Earphone K & S Diver 3 Microphone U & V Diver 3 Earphone Y & Z Diver 4 Microphone X & W Diver 4 Earphone J & T Tender Microphone P & Q Tender Earphone D & N Recorder Output C & R Push-To-Talk 9

CONTROLS & CONNECTIONS OPTIONS 5.7 CALL INDICATOR 4002 Lock Indicator - LED Lamp indicates a call originating from a lock, lamps are provided for each lock. Call Annunciator - Alerts the operator of a call. HELIUM SPEECH UNSCRAMBLER /26DSP2 The /26DSP2 option is located in the option section of the front panel assembly. ON/OFF SWITCH: Allows the selection of air or helium operation. In the OFF position the audio bypasses the Unscrambler. In the ON position the audio is processed by the Unscrambler, allowing for the correction of the helium speech. TREBLE BOOST: This control allows the High Frequency response of the unit to compensate for high frequency fall-off of the diver microphone. The Treble Boost control has five selections ranging 1-5. The treble boost feature allows for optimum frequency enhancement and improved intelligible speech from the diver s voice. DEPTH CONTROL: Selects the amount of frequency shift required to process the diver voice back to an intelligible level. The frequency shifting algorithm changes the amount of correction to the raw helium speech. MODE SWITCH: This switch performs two functions, Mode A/B and Noise Reduction Filter. MODE A/B: Selects two different processing modes for the correction of raw helium speech. Mode A is typically used for shallow depths with lower concentrations of Helium, while Mode B is used for deeper depths requiring higher concentrations of Helium. There is no specific depth limit for either mode; both are capable of operating to the maximum depth of 2000 FSW. Based on the mode setting, the frequency shifting algorithm s function will automatically change as well. NOISE REDUCTION FILTER (NRF): Incorporates a complex DSP algorithm which filters out background noise while allowing the diver s speech to be clear and intelligible. Amron NRF automatically captures the frequency spectrum of applied background noise within the audio frequency bandwidth and reduces it without affecting the diver s speech. The NRF has four adjustment levels for the reduction of background noise in both depth modes A & B. When in mode A, simply toggle the Mode Switch from A to B and back to A. In mode B, simply toggle the Mode Switch from B to A and back to B. Each time a toggle cycle is completed, the filter will advance to the next level. Based on the filter level, the operator will hear a number of beeping tones from 1-4 that corresponds with the blue LED indicators. NRF INDICATOR: There are four blue LED indicators that correspond to the present setting of the noise reduction filter ranging 1-4. 10

CONTROLS & CONNECTIONS OPTIONS (continued) 5.7 WIRELESS TENDER, /28FDW OPTION - This option is mounted in the right hand side of the front panel. This Wireless Tender Option is for four-wire (Simulcom) operation only. System comes standard with a remote wireless tender module. WIRELESS OPTION PANEL: Comes standard with antenna and power on/off switch. The ON/OFF switch powers the wireless PC card inside the communicator. IMPORTANT: When the wireless option is not used, turn the option panel switch to OFF. When option panel switch is turned ON, the wireless remote should be ON. Otherwise a static noise may be heard through the communicator s panel speaker as it scans for available Remote Wireless Tender. REMOTE WIRELESS TENDER MODULE: This module comes standard with an internal rechargeable battery. Headset and external 110V charger jacks are located on remote module. ON/OFF-VOLUME CONTROL: Adjusts the listening volume and turns the unit OFF when it is turned completely counter clockwise. TALK PUSH BUTTON: This button is located next to antenna. When button is in the UP position, the remote wireless is in the Standby Mode (listen only). When button is in the DOWN position, the remote wireless is in the Talk Mode (listen and talk, full duplex). Manufacture s default setting is DOWN. CHANNEL SELECTIVITY BUTTON: Located next to On/Off-Volume control. When button is in the UP position, the remote wireless operates as channel A. When button is in the DOWN position, the remote wireless operates as channel B. Manufacture s default setting is channel A. Both communicator and remote wireless have to be working on the same channel. BATTERY INDICATOR: Located next to ON/OFF volume control, this LED indicates the condition of the internal battery. When the LED is off when battery voltage is good. Red light is on when battery voltage is low or charger is plugged into module. CHANNEL Indicator: There is bicolor LED indicator located next to each channel button. LED function change based on setting of push buttons: ON-Red: Channel Button UP & Talk Button DOWN. ON-Green: Channel Button UP, Talk Button UP, and communicator wireless option is OFF. ON-Yellow: Channel Button UP, Talk Button DOWN, and communicator wireless option is ON. OFF: Channel Button DOWN. HEADSET JACK: Located on the side next to ON/OFF-Volume Knob. Plug the remote wireless headset to this Jack. CHARGE JACK: Located on the side next to antenna. Plug the remote wireless charger to this jack. 11

CONTROLS & CONNECTIONS 2-WIRE CONECTION MODEL 2840R 5.8 12

CONTROLS & CONNECTIONS SIMULCOM 4-WIRE CONNECTION MODEL 2840R 5.9 13

CONTROLS & CONNECTIONS PUSH TO TALK MICROPHONE CONNECTION, MODEL 2840R 5.10 14

CONTROLS & CONNECTIONS HEADSET CONNECTION MODEL 2840R 5.11 15

INSTALLATION & OPERATION OPERATION 6.1 The Model 2840R/24/XX AMCOM IV rack mount diver communicator is designed to mount in a standard electronic equipment rack, 19 inches wide. The unit has connections located on both the front and rear of the enclosure to facilitate system wiring. For system installation all connections can be made to the rear of the unit, eliminating the need for wires coming from the front panel. The AMCOM IV panels are graphically divided into six sections; Tender, Diver 1, Diver 2, Diver 3, Diver 4, and Options. Items within these areas are functions or controls relating to the tender, divers or optional items. POWER ON 6.2 When the unit is connected to AC power the LED power indicator in the TENDER section of the front panel will illuminate, confirming the presence of AC power. The AMCOM IV is designed to operate from AC voltage (110/220 VAC 60/50 Hz). This option includes two 6 volt gel cell batteries (connected in series for 12 VDC) for backup operation in the event of loss of AC power. The switch over to battery operation is completely automatic, and occurs whenever AC power is interrupted. The internal 12 volt battery is maintained at full charge while the unit is operating from AC power. WARNING: ALL AC POWERED EQUIPMENT SHOULD BE USED WITH A GROUND FAULT INTERRUPTER. ALL GROUND FAULT INTERRUPTERS HAVE A BUILT IN TEST CIRCUIT, CHECK FOR PROPER OPERATION BEFORE USING. CAUTION: ALWAYS EXERCISE EXTREME CAUTION WHEN OPERATING PORTABLE AC POWERED EQUIPMENT, ESPECIALLY WHEN OUTDOORS, WHEN CONDITIONS ARE DAMP OR WET OR WHEN WORKING AROUND OTHER EQUIPMENT. NEVER OPERATE UNIT WITHOUT EARTH-GROUND OR WITHOUT A WORKING GROUND FAULT INTERRUPTER. WHEN IN DOUBT DISCONTINUE USE IMMEDIATELY AND HAVE A QUALIFIED ELECTRICIAN INSPECT YOUR EQUIPMENT BEFORE USING. The operating time of the battery pack is approximately 8 to 10 hours, depending on the condition of the batteries, options installed, and state of charge. Battery life is rated at 300 charge cycles, or 3 years. As with all batteries, gel cells must be treated with a certain amount of care to achieve full life cycle. The most important single factor is not to continue to use the battery when the battery is discharged. The second precaution which must be followed is the prompt recharging of discharged batteries. Never store the unit with batteries discharged. If the unit is not going to be used for an extended period of time, the batteries should be charged at least once every 6 months. 16

INSTALLATION & OPERATION MODES OF OPERATION 6.3 The AMCOM IV has the capability of 2-wire and/or Simulcom (4 wire) communication modes. 2-Wire and Simulcom can be used simultaneously (divers on Simulcom, tender on 2-wire). NOTE: The mode of operation is determined by the wiring of the Divers Umbilical. The preferred method of operation is the Simulcom (4-wire) mode. 2-Wire communication is defined as a single communication path; normally the diver(s) is the priority signal path with the tender listening to diver(s). The signal path is reversed by pushing the push to talk switch; the diver(s) then hears tender. Often times a 4-conductor (4 wires) communication cable is used with 2 wires tied together as a pair for redundancy; this is still a 2-wire system as there is only one signal path. Simulcom communication is defined as a dual communication path; a signal path for the up-link (diver to tender) and a signal path for down link (tender to diver). Each path requires twisted pair of wires in the cable. A common example of Simulcom communication is the telephone. This permits the freedom of natural communication, lower system noise, and diver to diver communication without having to attempt cross-talk switching. For an in depth discussion on Simulcom refer to Simulcom, what, why, and how!" located in the theory of operation section of this manual. 2-WIRE OPERATION 6.4 The communications cable from the diver s umbilical (hat/helmet) to Diver 1, Diver 2, Diver 3 and/or Diver 4, is connected to the appropriate diver input. See theory of operation for details on how to wire the umbilical. In 2-wire the tender must press the Push to talk switch to be heard. If you are using the Amron remote walk and talk, Model 2821-28, the tender may press the push to talk switch on the belt module. Turn unit on and adjust volume controls as follows. VOLUME CONTROLS NOTE: The upper row of volume controls control up-link volume, the lower row of volume controls control down-link volume. Controls within a given row are interdependent. Tender controls are considered master controls. The optimum settings are when controls are closely matched, with differences compensating for differences in diver levels. Set all volume controls to mid-scale. VOLUME CONTROLS (TENDER) DIVERS TO TENDER - Adjust to comfortable level TENDER TO DIVERS - Adjust to comfortable level VOLUME CONTROLS (DIVER 1, DIVER 2, DIVER 3 & DIVER 4) TENDER TO DIVER - Adjust to comfortable level DIVER TO TENDER - Adjust to comfortable level 17

INSTALLATION & OPERATION OTHER DIVER CONTROLS 6.5 DIVER PTT SWITCHES: Depressing the appropriate PTT switch, will allow the tender to talk to only that diver when in the 2-wire mode of operation. The switch is spring-loaded and will automatically reconnect when the switch is released. CROSS TALK SWITCHES (DV-W to X, Y & Z) the cross talk switches allow conversations from diver to the other three divers in the two wire mode. Cross-talk between divers must be tender-operated via the cross-talk switches. For example, cross-talk DV-1 to DV-2, 3 & 4, allows diver 1 to speak to (but not hear) diver-2, diver-3, and diver 4. The tender will hear conversations on speaker or headset. SIMULCOM (4-WIRE) OPERATION 6.6 Connect the Diver 1 s Umbilical to the Diver 1 input. Repeat the same for diver 2, 3 & 4. Connect tender headset earphones to Headset jack, and headset microphone to Tender Microphone jack. Turn speaker off to avoid acoustic feedback. Operation with speaker is possible by extending tender's headset away from the speaker. Use Amron Model 2822-28 headset extension cable (25 foot). Turn unit on and adjust volume controls as follows. VOLUME CONTROLS: Volume controls are separated into two groups: up-link (top row), and down-link (bottom row). Set all volume controls at mid-scale. Tender should don headset and talk to himself. If adjustments are required, increase or decrease volume (controls). This will establish a system volume level. TENDER (VOLUME CONTROLS) DIVERS TO TENDER - Use as a master control TENDER TO DIVERS - Use as a master control Have divers talk one at a time, while tender adjusts to a comfortable listening level. Tender then talks and the divers determine a comfortable listening level having the tender adjust as needed. VOLUME CONTROLS (DIVER 1, DIVER 2, DIVER 3 & DIVER 4) DIVER TO TENDER - Diver talks, while tender adjusts to a comfortable listening level. TENDER TO DIVER - Tender talks and diver determines a comfortable listening level. After adjusting Diver 1 controls, repeat the procedure with Diver 2, 3 & 4 controls. If conditions change as a group, the tender volume controls can be used as master volume control. Depressing the appropriate PTT, within the divers section of the panel will allow the tender to talk to a particular diver. The switch is spring loaded and will automatically reconnect the diver's microphone when the switch is released. 18

INSTALLATION & OPERATION SIMULCOM (4-WIRE) OPERATION (cont d) 6.6 Operating the PTT and/or Diver Cross-talk switch will establish a priority channel for communication. The PTT switches cuts out the diver's microphone and prevents diver(s) from talking. This allows an important conversation to be carried on with out interruption, or the ability to establish a clear channel of communication. Note: When operating with a standby diver who does not have his hat/helmet on, acoustic feedback may occur. This can be avoided by turning his volume down (Diver to Tender), which cuts off his microphone, yet will enable him to monitor the diver/tender conversation. OTHER TENDER CONTROLS 6.7 SPEAKER ON/OFF SWITCH - for normal operation the speaker switch is left on. When operating in noisy conditions, it may be advantageous to use a headset to cut out the background noise. In this case it will be desirable to shut off the speaker. There are other conditions when turning off the speaker is desirable, situations where the nature of the work requires a confidential handling of communications. PUSH-TO-TALK SWITCH - activation of this switch connects the tender to the diver, necessary for two wire conversations, optional for Simulcom (4-wire) conversations. Always used when using the speaker for talking to the divers. MICROPHONE JACKS (RED) - connection for headset microphone. Plug red banana plug into these jacks when operating in the Simulcom mode. HEADSET JACKS (BLACK) - connection for headset earphones, external speaker. Plug both headset banana plugs (red & black) into the black headset jacks, red & black when operating in the two wire mode. Plug in only the black headset banana plug when operating in the Simulcom mode. Plug hand held microphone black banana plug into the black headset jacks. PUSH TO TALK JACKS (YELLOW) - connection for remote control of the push-to-talk function. Plug the hand held microphone yellow banana plug into this jack. Operation of the hand held microphone is simple and straight forward, hold the microphone in your hand, place the microphone within one half inch of your mouth, depress lever on side of microphone and speak clearly and distinctly into the microphone. The Model 2840R has an automatic speaker disconnect relay which disconnects the front panel speaker and microphone when using the hand held microphone. This greatly reduces the background noise during transmissions to the divers. This feature is also functional when using the AMRON headset, and headset extender (Model 2822-28). TAPE RECORD JACK (Rear panel) an electrically isolated audio output to drive a audio tape recorder or VCR. Use standard RCA type audio cable to connect the diver radio to the audio recorder. Test record audio, checking both tender to diver conversation and diver to tender conversation for proper record levels. 19

INSTALLATION & OPERATION OTHER TENDER CONTROLS (cont d) 6.7 HELIUM UNSCRAMBLER - The helium unscrambler option is installed into the option panel on right side of the unit. Diver communicators configured with this option are only supplied with the AC power option. This is due to the power requirements of the unscrambler option. The communicator can be operated in the air mode by turning off the helium unscrambler. Operation of the helium unscrambler involves turning the unit on and adjusting the depth control to provide the proper amount of voice correction. The unscrambler offers two modes of operation, mode A and mode B. The mode to use is generally related to depth. At depths less than 300 FSW, mode A is recommended. For depths greater than 400 FSW, mode B is recommended. There is an overlap between 300 to 400 FSW where it is user preference. Either mode of operation can be used at any depth; the amount of correction available is not limited by the mode, only the style of correction changes. The selection of Mode should be up to the preference of the operator as to which mode is appropriate with the selection based on the intelligibility of the speech. A treble control is provided to enhance the diver s microphone performance. Helium voice is composed of higher frequency components and microphone operation and performance is critical for proper operation. The treble adjustment allows the operator to provide frequency enhancement or correction to enhance the intelligibility of the diver s speech. Adjustment is done by subjective method, what sounds the best and is the easiest to understand. The depth control is used to change the amount of shift in the frequency of the diver s voice. The depth control is advanced as the diver s depth increases. There is a certain amount of interaction between the controls, and also a difference between diver voices, therefore it is necessary to tune the unit to the diver. Intelligibility is the desired result; each operator will find a combination which works best. SIMULCOM - WHAT WHY AND HOW 6.8 Simulcom is a communications system designed from the ground-up to take advantage of the current state of the art in semiconductor technology and to provide superior diver hard wire communication. First, the advantages and then an explanation of What, Why, and How 1. 285% More signal from the divers microphone (over 2-wire), using your existing 8 ohm microphone! 2. No Push-To-Talk Required! 3. No special diver communication wire required! 4. Diver hears himself talk! 5. Diver to diver communication without having to operate any controls. Just like a telephone! These advantages are real and can be readily demonstrated. The system is simple, easy to operate, and easy to trouble shoot (in fact, easier than 2-wire once you understand what's happening). 20

INSTALLATION & OPERATION SIMULCOM - WHAT WHY AND HOW (cont d) 6.8 It pays off in good communication. Better communication means higher production, safer diver conditions, and less down time. Now that we have made these claims, allow us to explain why and how. First, let's define some basic industry terms so that we can all start from the same point. 1. 2-Wire is used almost exclusively in the diving industry. It is technically defined as a single communication path, a minimum of 2 wires. Normally, the diver is the priority path (tender listens to diver). Signal reversing is accomplished by pushing the "Push to talk" switch (diver hears tender). Generally, most diver communications cables have 4 wires i.e., "Army surplus commocable". Most often the wires are twisted together to create a pair, this is still a 2-wire system. The tying together is done for redundancy. 2. 4-Wire communication is defined as a dual communication path. The first communication path (a pair of wires) is used for the up-link as in 2-wire and a second communication path (a pair of wires) is used for the down-link. This allows voice communications to go in both directions at the same time. A common example of "4-wire" like communications is the telephone. A telephone system which required a push to talk would be antiquated today. Another example is a system called Round-Robin. Round-Robin is a step in the right direction, however, only a half step. It has several advantages and some disadvantages which we will get into later. Remember Simulcom and round robin are not the same. WHAT IS SIMULCOM? It is a dual signal path system, with special amplifiers to take care of the problems associated with Round-Robin. It allows everyone on the circuit to talk to each other just as if you were on a telephone. WHY ARE SPECIAL AMPLIFIERS NEEDED? One of the big problems with Round-Robin is oscillation, also known as feedback. This can occur in two ways. The first is acoustic feedback which occurs when you have an open microphone next to a speaker. What happens is a noise comes out of the speaker, which is then picked up by the microphone amplified and sent back to the speaker which now is a larger noise. This process repeats itself until the amplifier hits the Rails (the signal is as large as the amplifier can handle). The solution to this problem is to turn down the amplifier and put someone's head between the speaker and microphone. The second problem is much more difficult to deal with. With two communication paths (up-link and down-link) one path is carrying a large signal (to drive the speakers) and one path a small signal (from the microphone). The signal to the speaker may be several volts, say 4.0 V and the typical output of a microphone may be 0.004 V. As you can see the large signal may be 1000 times larger than the small one. If part of this signal couples across, we again have feedback. One solution is to use shielded pairs to prevent this cross coupling, effective but expensive. Another solution is to use an amplifier which has common mode rejection. This basically means if the signal on both wires is the same the amplifier will ignore it, if the signal is different, it will amplify it. So with Simulcom we ignore the common signals and look for and amplify the different signal from the microphone. This is a simplification of CMR designs and an over-simplification of the many design rules one must abide by when designing circuits for CMR. 21

INSTALLATION & OPERATION SIMULCOM - WHAT WHY AND HOW (cont d) 6.8 This technology is not new to the electronics industry; it has been used quite extensively since the late 60's in signal processing systems. Current technology produces integrated circuits which make this easier to implement. The AMCOM series of diver communications was the first designed to implement this technology for diver communication. There are several other advantages to this system as implemented in the AMCOM II series. Because Amron uses an independent amplifier for each circuit, i.e., Diver 1, 2, 3 and 4 and Tender, each microphone has its own amplifier. This allows us to preserve CMR and provide less loading for each microphone. Example - in two wire operation we have each diver with one microphone and two speakers all tied together. When you talk into the microphone it puts out a signal which we are going to amplify. Part of this signal is absorbed by each earphone, one earphone across a microphone reduces the output of the microphone by 50%, the second earphone further reduces the signal to 35%. So by splitting the microphone from the earphones we have an immediate 2.85 times larger signal from the microphone. As you can see for the same signal level out we can turn down the gain (less noise is amplified), the system stability is better with a tremendous improvement in clarity. DOESN T THE SAME THING HAPPEN WITH ROUND-ROBIN? No. With Round-Robin you split the microphone and earphones, but stack all the microphones together. The microphones load each other and you are right back where you started. Also, you have another problem - the headset used by the tender usually has 600 Ohm earphones and a 50 Ohm microphone. With two diver microphone's we have an impedance of 4 Ohms which really loads the tender microphone and the 600 Ohm earphones tend to be rather low so you end up with a volume imbalance as well as low signal levels from the diver & tender microphones. What is required to implement Simulcom? Okay - step by step: 1. You must have 4 wires in your communications cable. 2. You must have 4 wires to your hat/helmet, (i.e., Marsh Marine connector or such). With those three things we can begin: 1. Install male marsh-marine 4 pin connector in hat/helmet. Attach the black and white wires to the binding posts along with the leads from the speakers. Black wires on one of the posts and white wires on the other. Attach the red wire to one of the wires from the microphone, and attach the green wire to the other wire from the microphone. Use 8-32 X ¼ stainless steel screws, and cover the screw and nut with shrink tubing or tape. You have now finished the hat. 2. Install 4 pin female marsh-marine connector to the divers end of the comm. cable. Red and green to the light colored pair of wires, and black and white to the dark colored pair of wires. You are now finished with this step. 3. Install black dual banana plug to the dark colored wire of the communication cable at the surface end. Install red dual banana plug to the light colored wires. You are finished! 22

INSTALLATION & OPERATION SIMULCOM - WHAT WHY AND HOW (cont d) 6.8 TO OPERATE AND/OR CHECK OUT SIMULCOM 1. Attach hat to umbilical. 2. Attach communications-cable to AMCOM IV red banana plug to the Diver 1 microphone input jacks, and the black to the Diver 1 earphone jacks. You can also use the MS connector on the rear of the unit using the corresponding pins of the connector. 3. Don hat and talk to yourself and if you hear your voice over the earphones the system is working. TO RECAP - we now have a system where diver 1's microphone is connected to via a separate set of wires to the AMCOM IV and Diver 1's earphone is connected via a separate set of wires to the AMCOM IV. All features such as diver push to talk switch and independent volume controls of the AMCOM IV remain intact. Tender uses a headset which is plugged into the tender microphone and headset jacks. With the AMCOM IV system you can mix 2-wire/simulcom systems, for example, Diver 1, 2 and 3 could be Simulcom while Tender can be 2-wire (no headset - use speaker for tender). Or, one Diver can be 2-wire and the others Simulcom. Just remember if any one person is 2-wire you must use the push-to-talk for those divers to hear. Other configurations which can be implemented with Simulcom systems: 1. Remote station for equipment operator, or second tender on 2-wire or Simulcom. 2. Several remote stations with any combination of 2-wire or Simulcom. MAINTENANCE 6.9 The inherent quality of your solid state AMC0M diver communicator will provide years of continuous failure-free service, if properly used and maintained. There are two important areas of user care which will determine the length of service you can expect from your equipment. 1. Take care of your equipment! Protect it, handle it with care, do not throw it around, set it down - don't just drop it. Select a work area where the equipment will be out of everyone's way, so that it doesn't get knocked over. 2. Clean your equipment! After the work is done at the job site, clean up the equipment. If you are on an extended work program, have the equipment operators clean the equipment during slow work periods. Cleaning involves: wiping off the dirt, use a damp cloth to wipe the front panel, and then spray the panel and case with silicone spray. Clean the terminals use mild vinegar and water solution and a small brush. Other than cleaning there is no additional maintenance required. 23

THEORY OF OPERATION THEORY OF OPERATION 7.1 Refer to the functional block diagram and schematics while reading this section. This Section describes the function of the electronic circuits. AMPLIFIER CARD 2832-204-03 7.2 There are two 2832-204-03 amplifier cards in the 2840R. Card 1 is the master card and handles Divers 1 & 2 as well as the tender circuits. Card 2 is a slave card that handles Dives 3 & 4. To distinguish between these cards, the prefix C1 will be used for components on Card 1 and C2 for components on C2. Each card has a separate fuse to protect it against over current conditions. The fuses on both cards, as well as the fuses on the battery charger Card 3, should be checked during troubleshooting. PREAMPLIFIER C1-U2, C1-U3, C2-U2 and C2-U3 are the differential microphone preamplifiers for Diver 1, 2, 3 and 4 respectively. Each diver preamplifier has a preamplifier microphone detector circuitry. This circuitry (C1-U5B, C1-U5C, C2-U5B and C2-U5C) provides the bias current required by the microphone preamplifier and adjusts the gain of the 2840R preamplifiers to prevent the signal from being overdriven. Each diver preamplifier has independent microphone detection. This allows for a mixture of diver using dynamic and preamplified microphones. C1-U1 is a differential pre-amplifier for the tender circuit. This circuit does not have the microphone preamplifier detection circuitry. MICROPHONE VOLUME CONTROL - The signals from the diver preamplifiers are attenuated through diver microphone volume controls. Each individual microphone signal can be adjusted before going to mixer C1-U6A. The tender s microphone volume has a separate volume control that attenuates the signal before going through the Diver/Tender Mixer C1-U6B. MIXER C1-U6A mixes the attenuated microphone inputs from the divers. The resulting signal is a mixture all at the diver signals and can be sent to an optional Helium Speech Unscrambler (HSU) unit for saturated diving applications. C1-U6B mixes the divers microphone signal, either directly from C1-U6A or from an optional HSU, with the tender microphone signal. If installed, the signal from the optional wireless tender is inserted at this stage. BAND PASS FILTER C1-U7A filters the signal for maximum intelligibility. The mixed tender and diver signals is filtered and sent out to the various diver and tender earphone volume controls. The filtered signal is also set to C1-U5D. This amplifier drives the signal through a transformer (T1) to provide an electrically isolated recorder output. AUDIO POWER AMPLIFIERS C1-U9-1, C1-U9-2, C1-U10-1, C2-U9-2 and C2-U10-1 are the audio power amplifiers for the tender and divers 1-4 respectively. The output levels "floats" at approximately 6 volts and should never be connected to ground. 24

THEORY OF OPERATION The input signal to each power amplifier is attenuated by tender and diver volume control. Each individual earphone output level can be adjusted before going to relays. RELAYS - The amplified audio output signal from the audio power amplifiers are directed to Divers and Tender through relays C1-K2, C1-K3, C1-K4, C2-K3 and C2-K4. These relays are used in the two-wire mode. For the divers, the associated relay directs the microphone jack to the microphone pre-amplifier. When a Push-To-Talk or Crosstalk switch is pressed, the appropriate relay(s) are switch connecting the amplified signal to the microphone jack. The relay activated by Push-to-Talk and Cross-Talk Switches in a certain function that determined by the PTT Logic PCA (CARD 4). BIAS LEVEL Resistor R77 and Voltage reference C51 determine the bias voltage for the amplifiers U1, U2, U3, U4, and U5. It should be 5.0 volts measured to ground +/- 1%. AUDIO VOLUME CONTROLS 7.3 2-WIRE OPERATION - Input audio signals from divers are amplified through the circuitry described previously, and directed to the tender's headset and speaker through relay C1- K1. When tender actuates the push to talk switch, tender's speaker and headset are connected through relay C1-K1 to microphone input. Divers are connected to audio output through relays C1- K2, C1-K3, C2-K2 and C2-K3. SIMULCOM (4-WIRE) OPERATION - Tender and diver microphone are connected to amplifier inputs at all times. Tender headset and diver earphone are connected to audio output at all times. BATTERY CHARGER CARD, 2324-202 7.4 The battery charger card is used in both the /23 & /24 options. The 2324-202 converts the AC power from the transformer T1 to a regulated DC voltage to operate the unit and charge the batteries. It maintains batteries at float charge of 13.8 To 14.4 Volts. Front panel AC power LED, indicates when AC power is applied to unit. Charger protects batteries from overcharge by automatically switching to float charge when batteries are fully charged. The power supply is automatically detecting the 110 or 220 AC voltages and adjusting the transformer winding for the proper voltage setting. This is performed by a solid-state comparator and FET transistor. No switch is provided for the customer to set, this is normal. The customer is still required to change the power cord to one appropriate for their location. AMRON can provide and install a special cord as a custom modification, if the customer so orders. There are 3 fuses located on the printed circuit card. They have been mounted in socket holders. The fuses are small round cylinders about the size of a pencil eraser. Fuses are a single use safety device. They interrupt the current in the event of a massive short circuit. Our fuses are set high enough that nuisance tripping should not occur. Consequently, a qualified technician should investigate a blown fuse properly. The unit should be examined for the cause of the failure, and its safe operation verified before replacing the fuse and returning the unit to the field. 25

THEORY OF OPERATION OPTION /26DSP2 HELIUM UNSCRAMBLER 7.5 The helium unscrambler card takes audio information coming from the diver amplifiers and corrects for the effect of helium breathing gas on the divers voice. The corrected audio is then fed back to the mixer. The technique used by the Amron helium unscrambler, is to convert the audio analog information to digital, store the digital information, and recombine the digital information so as to reconstruct the audio without the frequency shift caused by the helium gas. No additional information is provided on the helium unscrambler for two reasons. First very few companies have the expertise necessary to repair or service helium speech unscramblers. Second, the information is proprietary to Amron and not for the public. 26

THEORY OF OPERATION FUNCTIONAL BLOCK DIAGRAM L 2840R SHEET 1 OF 3 7.6 27

THEORY OF OPERATION FUNCTIONAL BLOCK DIAGRAM L 2840R SHEET 2 OF 3 7.6 28

THEORY OF OPERATION FUNCTIONAL BLOCK DIAGRAM L 2840R SHEET 3 OF 3 7.6 29

MAINTENANCE DIVER RADIO FIELD CHECK PROCEDURES 8.1 The following procedures are a step by step procedure to do a functional check of your radio, using only a headset. These steps check all communication functions of the radio in both 2-wire and Simulcom modes. This means that if your radio checks OK with these steps, any communication problems may be somewhere else in the system, such as umbilical, connections, speakers, and/or microphone. Quick Simulcom check - this brief procedure checks diver radio functions in Simulcom: set all volume controls at mid-scale, turn unit on, turn speaker off. QUICK SIMULCOM CHECK 8.2 This brief procedure checks diver radio functions in Simulcom: set all volume controls at mid-scale, turn unit on. Tender Circuit Check 1. Identify headset microphone lead and headset earphone lead. Plug into dual banana jacks. (The microphone plug is red.) 2. Plug in headset microphone to tender microphone (input) and headset earphone to tender headset (output). You should be able to hear yourself talk. This verifies Tender circuit. 3. Move headset microphone to Diver 1, Microphone (Red 5-way binding posts) and headset earphones to Diver 1, Earphone (Black 5-way binding posts). You should be able to hear yourself talk. This verifies diver 1 circuit. 4. Move headset microphone to Diver 2, Microphone (Red 5-way binding posts) and headset earphones to Diver 2, Earphone (Black 5-way binding posts). You should be able to hear yourself talk. This verifies diver 2 circuit. 5. Move headset microphone to Diver 3, Microphone (Red 5-way binding posts) and headset earphones to Diver 3, Earphone (Black 5-way binding posts). You should be able to hear yourself talk. This verifies diver 3 circuit. 6. Move headset microphone to Diver 4, Microphone (Red 5-way binding posts) and headset earphones to Diver 4, Earphone (Black 5-way binding posts). You should be able to hear yourself talk. This verifies diver 4 circuit. The basic Simulcom function of the diver radio has now been checked. 30