User Manual

For
Amron International Diving Supply, Inc.

MODEL 2830R/24/XX
Three 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 © 2010 AMRON INTERNATIONAL, INC.

REVISED FEBRUARY 2011
 TABLE OF CONTENTS

Specifications 1

General Information 2
General Information ......................................................................................................2.1
Drawing Front Panel Controls Model 2830R.................................................................2.2
Drawing Front Panel Options ........................................................................................2.3

Options 3

Warranty & 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, Push to Talk Microphone Connection ..........................................................5.10
Drawing, Headset Connection ....................................................................................5.11

Installation & Operation 6

Operation ......................................................................................................................6.1
AC Power ......................................................................................................................6.2
Battery Condition Check ...............................................................................................6.3
Battery Installation.........................................................................................................6.4
Modes of Operation.......................................................................................................6.5
Volume Controls 2-Wire ...............................................................................................6.6
Other Diver Controls 2-Wire .........................................................................................6.7
Volume Controls 4-Wire (Simulcom) ............................................................................6.8
Other Diver Controls 4-Wire .........................................................................................6.9
Other Tender Controls ................................................................................................6.10
Options........................................................................................................................6.11
Simulcom - What Why and How .................................................................................6.12

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 TABLE OF CONTENTS

Theory of Operation 7
Theory of Operation ......................................................................................................7.1
Amplifier Card 2832-202 ...............................................................................................7.2
Audio Output Volume Controls......................................................................................7.3
Battery Charger Card, 2324-202...................................................................................7.4
Option /26DSP2 Helium Speech Unscrambler .............................................................7.5
Option /28FDW Wireless Tender ..................................................................................7.6
Functional Block Diagram .............................................................................................7.7

Maintenance & Trouble Shooting 8

Diver Radio Field Check Procedures ...........................................................................8.1
Quick Simulcom Check .................................................................................................8.2
Comprehensive 2-Wire & Simulcom Check ..................................................................8.3
Problems and Possible Causes ....................................................................................8.4

Drawings & Schematics 9

General .........................................................................................................................9.1
Schematic 2830R/24.....................................................................................................9.2
Schematic Option /26DSP2 ..........................................................................................9.3
Schematic Option /28FDW............................................................................................9.4
Schematic 4002 Option.................................................................................................9.5
Parts Identifier, 2832-203..............................................................................................9.6
Parts Identifier, 2324-202..............................................................................................9.7
Parts Identifier, Front Panel Model 2830R/24 ...............................................................9.8
Parts Identifier, Options /26DSP2, /28FDW, -4002.......................................................9.9

Parts List 10
General Information ....................................................................................................10.1
2830R/24 Top Assembly.............................................................................................10.2
2830R/24/26DSP2 Top Assembly ..............................................................................10.3
4002 Option.................................................................................................................10.4
2830R-400 STD Front Panel Assembly ......................................................................10.5
2830R/26-400M DSP2 Front Panel Assembly............................................................10.6
2830R-4002-400M Call Front Panel Assembly...........................................................10.7
2825R-500D Chassis Assembly .................................................................................10.8
2825R-500M Chassis Assembly .................................................................................10.9
2823-6002 Charger Assembly ..................................................................................10.10
2324-202 Power Supply Card Assembly ..................................................................10.11
28XXR-FS Shop Spares Kit ......................................................................................10.12
Optional PC card Spares ..........................................................................................10.13

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 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.................................................................... 0.25 Amps
Output Impedance ............................................................................................................... 4 Ohm
Power Supply Voltage ......................................................................................... 12 VDC Nominal
(9 Volts Minimum - 18 Volts Maximum)
Sensitivity (Input) .................................................................................................................0.5 mV
Output Power (RMS @ 4 Ohm Load, 12 VDC) ......................................................20 Watts Audio

Battery Life…………………………………………………………………………….………….10 Hours

Operating Voltage…………… ……………………………………………………………………12 VDC
AC Power………………………………………………………………..…..110/220 Volts AC 50/60 Hz

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)

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 GENERAL INFORMATION

GENERAL INFORMATION 2.1

The AMCOM Rack Mount series of diver communication systems are full feature hard wire, three
diver communicators.

The units are 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.

All standard units can be operated from either a 110/220 VAC and internal 12 VDC battery.

The AMCOM III has the capability of 2-wire and/or Simulcom (4-wire) communication modes. 2-
Wire and Simulcom (4-wire) modes can be used simultaneously. Simulcom is a communications
system designed from the “ground-up” to take advantage of the current “state of the art” in
semiconductor technology and provide superior diver hard wire communication.

This diving communicator has the ability to work with both dynamic and pre-amplified microphones
in either 2-wire or 4-wire modes. The circuit detects the type of microphone that each diver is
using then automatically switches from the preamp mode to dynamic mode, adjusting the specific
diver’s gain (volume).

2
 GENERAL INFORMATION

DRAWING FRONT PANEL CONTROLS MODEL 2830R/24 2.2

3
 GENERAL INFORMATION

DRAWING FRONT PANEL OPTIONS 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 feet (approx.), must be ordered with AC
option (Model /24).

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:

Amron International, Inc.

1380 Aspen Way
Vista, Ca. 92081

Be sure to include the following information:

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.

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 CONTROLS & CONNECTIONS

CONTROLS AND CONNECTIONS 5.1

Before using the AMCOM III series diver communications system, you should familiarize yourself
with its 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 III 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. It may be necessary to
turn speaker off when using a headset to prevent feedback.

PUSH TO TALK ALL DIVERS SWITCH – This Switch allows tender to divers
communication 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 tender microphone volume. Use as master

volume control, clockwise increases volume.

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.

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 CONTROLS & CONNECTIONS

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.

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. Short across jacks for
downlink, open for up-link.

DIVER CONTROLS 5.4

VOLUME DIVER TO TENDER (Diver 1, 2, & 3) - 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) - 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.

DIVER 1 TO DIVER 2 & 3 - In the two wire mode, the DV-1 TO DV-2 & DV-3 momentary
switch allows diver 1 to talk to diver 2 & diver 3, while the switch is depressed.

DIVER 2 TO DIVER 1 & 3 - In the two wire mode, DV-2 TO DV-1 & DV-3 momentary
switch allows diver 2 to talk to diver 1 & diver 3, while the switch is depressed.

DIVER 3 TO DIVER 1 & 2 - In the two wire mode, DV-3 TO DV-1 & DV-2 momentary
switch allows diver 3 to talk to diver 1 & diver 2, while the switch is depressed.

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 CONTROLS & CONNECTIONS

DIVER CONNECTIONS 5.5

MICROPHONE (input/output) (Applies to Diver 1 & 2 & 3) - 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 system 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’s (up-link &
down-link) are switched automatically when push to talk switch is actuated. When a pre-
amp microphone is used in the 2-wire mode setup, it is required to have special speakers
supplied only by Amron.

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) - 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 system 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 - Military series connector, providing connections to Diver and Tender

inputs and outputs to facilitate connections without having to run wires to 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
H&F Diver 2 Earphone
S&K Diver 3 Microphone
U&V Diver 3 Earphone
J&T Tender Microphone
Q&P Tender Earphone
D&N Recorder Output
R Push To Talk
C Common

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 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.

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 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. Indicates the condition
of the internal battery. Light 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

DRAWING, 2-WIRE CONNECTION 5.8

12
 CONTROLS & CONNECTIONS

DRAWING, SIMULCOM (4-WIRE) CONNECTIONS 5.9

13
 CONTROLS & CONNECTIONS

DRAWING, OPERATOR CONNECTIONS, P.T.T. MICROPHONE 5.10

14
 CONTROLS & CONNECTIONS

DRAWING, OPERATOR CONNECTIONS, HEADSET 5.11

15
 INSTALLATION & OPERATION

OPERATION 6.1

The Model 2830R/24/XX AMCOM III 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 wires hanging from the front panel.

The AMCOM III panels are graphically divided into sections; Tender Controls, Diver Controls, and
Options. Items within these areas are functions or controls relating to the Tender, Diver(s) or
Optional items.

AC POWER 6.2

When the unit is connected to AC power the LED power indicator on the STATUS section of the front
panel will illuminate, confirming the presence of AC power.

The AMCOM III 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 rechargeable battery is maintained at full charge
while the unit is operating from AC power. AC power indicator on the optional panel confirms the
presence of AC power.

CAUTION: ALWAYS exercise extreme caution when operating portable AC powered equipment,
especially when outdoors, where conditions are damp or wet, or when 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.

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.

NOTE: Do not continue to operate rechargeable batteries below the low battery condition or
permanent damage will occur. When the battery condition indicator turns to red color, shut unit off
and charge batteries

16
 INSTALLATION & OPERATION

BATTERY CONDITION CHECK 6.3

POWER ON - BATTERY CHECK

Turn power switch “ON” and observe the battery condition indicator. The battery indicator will
display the condition of the battery.
A steady green light indicates the battery has sufficient voltage to operate the unit.
A blinking green light indicates the battery is low and will need charging shortly, 2 hours of
operating time remain.
A steady red light indicates the battery voltage is too low to operate the unit.
Communication should stop.

Operating time for the rechargeable battery depends upon the age of the batteries. Gel Cell
batteries have a life of 300 cycles, or 3 years. Gel Cell batteries do not have memory; therefore
they can be topped up (placed on charge) at any time.

NOTE: Batteries which have not been used for a period of time will display a higher voltage state
when initially turned on, this will rapidly dissipate. This condition is known as a surface charge,
when the battery is placed under a load the voltage will fall rapidly. It is a good idea to leave the
unit on for 5 minutes before relying upon the battery condition indicator.

BATTERY INSTALLATION 6.4

The unit is supplied with two gel cell sealed lead acid batteries and an internal charger. To remove
and install the battery, set unit on flat stable surface, disconnect all cables, and front panel power
switch to OFF. Remove the two screws associated for the top lid from rear panel. Remove top lid
cover. Remove the four screws located on the sides of the battery box. Lift out both old batteries.
Install the new batteries and close unit in the reverse order.

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 INSTALLATION & OPERATION

MODES OF OPERATION 6.5

The Model 2830R 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).

2-Wire communication is defined as a single communication path, normally the diver is the priority
signal path, tender listens to diver. Signal reversing is accomplished by pushing the push to talk
switch, diver 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.

Simulcom (4-Wire) communication is defined as a dual communication path, a signal path (a pair
of wires) for up-link and a signal path (a pair of wires) for down link. 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 Push to 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
Connect the communications cable from the divers umbilical (hat/helmet) to Diver 1 and/or Diver
2, microphone (input) under the words 2-wire. Wires should be well-fastened to the binding posts
and not touching each other. If more than one diver is connected to any Microphone (input), (Diver
1 or Diver 2), the divers on the same two terminals will not be able to cross-talk (talk to each
other).

The earphone connection is not used by the divers. The earphone jacks can be used to operate a
remote speaker. Both diver and tender conversations will be heard.

In 2-wire mode 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.

4-WIRE OPERATION
Connect the two wires from the diver’s microphone to the Microphone (input) Diver 1. Connect the
two wires from diver’s earphones to the Earphone (inputs) Diver 1. Repeat the same for diver 2.

Connect tender headset earphones to Headset (input), and headset microphone to Tender
Microphone (input). Turn speaker off to avoid acoustic feedback. Operation with speaker is
possible by extending tenders headset away from the speaker. Use Amron Model 2822-28
headset extension cable (25 foot).

Note: Diver microphone is louder in 4-wire than 2-wire operation.

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 INSTALLATION & OPERATION

VOLUME CONTROLS - 2-WIRE 6.6

NOTE: The upper row of volume controls, set the microphone volume, the lower row of volume
controls, set the earphone volume. Tender controls are considered master controls. The optimum
settings are when controls are closely matched, with differences compensating for differences in
diver levels.

Tender (Volume Controls)

DIVERS TO TENDER Volume - Divers talk, while tender adjusts to a comfortable listening
level.
TENDER TO DIVERS Volume - Tender talks while depressing PTT All Divers Switch,
divers determine a comfortable listening level, having the tender adjust as needed.

Diver 1 (Volume Controls)

TENDER TO DIVERS Volume - Tender talks while depressing Diver 1 PTT Switch, diver 1
determines a comfortable listening level, having the tender adjust as needed.
DIVERS TO TENDER Volume - Diver 1 talks, while tender adjusts to a comfortable
listening level.

Diver 2 (Volume Controls)

TENDER TO DIVERS Volume - Tender talks while depressing Diver 2 PTT Switch, diver 2
determines a comfortable listening level, having the tender adjust as needed.
DIVERS TO TENDER Volume - Diver 2 talks, while tender adjusts to a comfortable
listening level.

Diver 3 (Volume Controls)

TENDER TO DIVERS Volume - Tender talks while depressing Diver 3 PTT Switch, diver 3
determines a comfortable listening level, having the tender adjust as needed.
DIVERS TO TENDER Volume - Diver 3 talks, while tender adjusts to a comfortable
listening level.

OTHER DIVER CONTROLS – 2-WIRE 6.7

PTT All Divers Switch - Push to Talk to All Divers switch is located on the left bottom corner
below Power ON/OFF switch. This switch allows all divers to hear the Tender, it changes all divers
to be listening and tender in talking mode.

Cross Talk Switches - The cross talk switches allow conversations from diver to diver in the
two wire mode. Cross-talk between divers must be tender-operated via the cross-talk switches.
Cross-talk Diver 1 to 2 & 3 allows diver 1 to speak to (but not hear) diver 2 & 3. Cross-talk Diver 2
to 1 & 3 allows diver 2 to speak to (but not hear) diver 1 & 3. Cross-talk Diver 3 to 1 & 2 allows
diver 3 to speak to (but not hear) diver 1 & 2. The tender will hear conversations on speaker or
headset.

Diver PTT Switches (Diver 1, Diver 2 & Diver 3)

Diver Push to Talk switches located below earphone volume control for each diver section. PTT
will allow the specific diver to hear Tender and other divers, it change the diver to be listening and
tender in talking mode.

19
 INSTALLATION & OPERATION

VOLUME CONTROLS - 4-WIRE (SIMULCOM) 6.8

Turn unit on and adjust volume controls as follows.

NOTE: The upper row of volume controls, set the microphone volume, the lower row of volume
controls, set the earphone volume. Tender controls are considered master controls. The optimum
settings are when controls are closely matched, with differences compensating for differences in
diver levels.

Tender (Volume Controls):

DIVERS TO TENDER Volume - Divers talk, while tender adjusts to a comfortable listening
level.
TENDER TO DIVERS Volume - Tender talks and divers determine a comfortable listening
level, having the tender adjust as needed.
Diver 1 (Volume Controls):
TENDER TO DIVERS Volume - Tender talks and diver 1 determines a comfortable
listening level.
DIVERS TO TENDER Volume - Diver 1 talks, while tender adjusts to a comfortable
listening level.

Diver 2 (Volume Controls):

TENDER TO DIVERS Volume - Tender talks and diver 2 determines a comfortable
listening level.
DIVERS TO TENDER Volume - Diver 2 talks, while tender adjusts to a comfortable
listening level.

Diver 3 (Volume Controls):

TENDER TO DIVERS Volume - Tender talks and diver 3 determines a comfortable
listening level.
DIVERS TO TENDER Volume - Diver 3 talks, while tender adjusts to a comfortable
listening level.

OTHER DIVER CONTROLS (4-WIRE MODE) 6.9

Connect the Diver 1’s Umbilical to the Diver 1input. Repeat the same for diver 2.

Connect tender headset earphones to Headset (input), and headset microphone to Tender
Microphone (input). 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).

Operating the PTT (push-to-talk) switch will establish a priority channel for communication. PTT
cuts out the diver’s microphone and prevents divers 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.

20
 INSTALLATION & OPERATION

OTHER TENDER CONTROLS 6.10

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 jack 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 communicator has an automatic speaker disconnect relay which disconnects the front panel
speaker when using the hand held microphone. This greatly reduces the background noise during
transmissions to the divers. This feature is also functional when using an AMRON headset, and
headset extender (Model 2821-28).

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.

TAPE RECORD JACK (Rear panel) - Isolated audio output to drive an 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.

21
 INSTALLATION & OPERATION

OPTIONS 6.11
WIRELESS TENDER OPTION /28FDW

This option is installed in the right hand section of the panel. Amron’s Full Duplex (Simulcom™)
Wireless Tender is designed for the top-side tender to communicate to divers with hands-free
operation and no required buttons to push. This wireless unit allows mobility for the tender while
checking equipment and still maintaining constant contact with the divers. This Option can also be
used in the two wire mode to monitor the diver conversations, but not to talk to the diver.

The Wireless system comes standard with 40 channel combinations which gives the ability to use
up to 40 different radios set at different channels in close proximity without cross-frequency
problems. Additional 2829-01 Wireless Headset and Transceiver Kits can be purchased for use
with the Amcom as standby “listen only” devices, as only one headset on the system can have
listen and talk priority to the divers. The design allows the capability to add an unlimited number of
remote listen only headsets for topside personnel. The units operate on the FM band at 902-928
MHz up to a range of ¼ mile. There is no requirement for FCC approval because the RF Power is
only 200mW and transmitter output 50mV/m (FCC part 15).

The remote unit (transmitter/receiver) is housed in a rugged plastic casing that can be clipped to a
belt or slipped into a pocket. A single charge of the NiCad battery from the included AC adapter is
capable of operating (transmitting and receiving) continually for up to 5 hours. In standby mode,
battery will last for up to 8 hours. The standard headset is a tough over-the-ear single ear muff
design with adjustable boom microphone.

Operation of the unit is automatic; speaking into the remote unit transmits a RF signal to the diver.
Diver speaking activates the option, causing it to transmit a RF signal to the remote tender.
Because of the duplex operation the transmission occur in both directions at the same time.

In addition to the remote unit, there is a master transceiver inside the communicator. Both channel
selector switch (A&B) and dipswitches (located under the battery) accommodate 40 different
channels with operating frequency range 902-928MHz. Manufacture sets both wireless
communicator and wireless remote module to work on Channel A with dip-switches setting
1,1,1,1,0,0,0,0 (1 is ON). In order to change channel of operation, it is required to apply changes
to both units (communicator and remote). Manufacture recommends changing wireless channels
to be done by technician.

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 the available Remote
Wireless Tender.

OPERTATION: Turn option power switch to ON, turn remote unit ON/OFF Volume to ON, set
remote unit to Talk Mode (Talk Button is DOWN) and Channel A (Channel Button is UP), and plug
headset to remote unit.

At the remote unit, confirm that Battery Indicator (located next to ON/OFF Volume) should be OFF,
as indication that battery is good. Also confirm that Channel A Indicator is ON (Yellow).

When battery drains below operation level, Battery Indicator turns ON (RED), communication
becomes noisy and will cut out.

22
 INSTALLATION & OPERATION

OPTIONS (Continued) 6.11

HELIUM SPEECH UNSCRAMBLER OPTION /26DSP2

The Helium Unscrambler option is installed into the option panel located on right side of the
communicator. A Communicator with this option accommodates a wide range of operating depths.
This state of the art digital design can accommodate a multitude of functions ranging from the
correction of the diver’s raw helium speech to normal intelligible voice levels, advance treble boost
and complex noise reduction filters (NRF).

Diver radios configured with this option are only supplied with the AC power option. This is due to
the power requirements of the Unscrambler option. The radio can be operated in the air mode by
turning off the helium Unscrambler.

The Unscrambler offers two modes of operation, Modes A and B. 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. Based on the mode setting, the frequency shifting
algorithm’s function will automatically change as well.

Amron’s advanced 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.

The Treble Boost Control provides means of adjustment to enhance the diver’s microphone
performance. The treble boost feature allows for optimum frequency enhancement and improved
intelligible speech from the diver’s voice.

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. The frequency shifting algorithm changes the amount of correction to the raw helium
speech.

Simplex and Simulcom operations are possible with the Amcom Unscrambler. In Simplex mode,
the tender's push-to-talk switch interrupts signals from the diver. In Simulcom mode, the tender will
hear the diver at all times and tender must use a headset to talk to the divers without using the
push-to-talk switch. Use of a headset to monitor HeliOx speech is recommended to enhance
Intelligibility.

23
 INSTALLATION & OPERATION

SIMULCOM - WHAT WHY AND HOW 6.12

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. Simulcom has the following advantages:

1. 285% More signal from the divers microphone (over 2-wire), using your existing 8-ohm
microphone!

2. No push to talk!

3. No special diver communication wire required!

5. Diver hears himself talk!

6. 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).

SIMULCOM pays off in good communication, which after all these years is still a goal some have
yet to achieve. 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 communication cable has 4 wires i.e., “Army
surplus comm-cable”. 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 communications is defined as a dual communication path, a signal path (a pair of

wires) for up-link and a separate signal path (a pair of wires) for downlink. 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.

24
 INSTALLATION & OPERATION

SIMULCOM - WHAT WHY AND HOW (continued) 6.12

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 an open
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. (Grey matter does not transmit sound well).

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.

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 is the first designed
to implement this technology for diver communication.

We use an independent microphone amplifier for each circuit, i.e., Diver 1, Diver 2, Diver 3 and
Tender. This allows us to preserve CMR and provide less loading for each microphone. Let us
explain - 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.
Each earphone absorbs part of this signal, one earphone across a microphone reduces the output
of the microphone by 50%, and 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.

25
 INSTALLATION & OPERATION

SIMULCOM - WHAT WHY AND HOW (continued) 6.12

DOESN’T THE SAME THING HAPPEN WITH ROUND ROBIN? NO!

With Round Robin you split the microphone and earphones, but also 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's microphones 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.

So it sounds as though it might be worth trying; how do you go about doing it?
Okay - step by step:

1. First you must have an AMCOM III series unit.

2. You must have 4 wires in your communication cable.

3. 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 black and white wires to
binding post and both speakers. Attach red and green wires to leads from microphone. It
doesn’t matter which color goes to which lead. Use 8-32 x 1/4 SS screw and nuts, cover
each with tape or shrink tubing. You are now finished with the diving hat/helmet.

2. Install 4-pin female marsh-marine connector on diver's end of communication cable with
red and green wires to the light colored pair of comm cable wires and black and white
wires to black pair of comm-cable wires. You are now finished with this step.

3. Install black dual banana plug to black pair of wires on tender end of diver comm-cable
and attach red dual banana plug to lighter color pair of wires. If you don’t have red dual
banana plugs, red tape will serve to identify that pair as the microphone circuit.
YOU ARE FINISHED!

26
 INSTALLATION & OPERATION

SIMULCOM - WHAT WHY and HOW (continued) 6.12

TO OPERATE AND/OR CHECK-OUT SIMULCOM

1. Attach hat to umbilical.

2. Attach comm-cable to AMCOM III, red banana plug to Diver 1 microphone, black banana
plug to Diver 1 earphone.

3. Don hat and talk to yourself; if you hear your voice over the earphones the system is
working.

To revert back to 2-wire, remove black banana plug from earphone jacks (AMCOM III) and plug
into top of microphone banana plug (red).

TO RECAP - We now have a system where diver 1’s microphone is connected to the Diver 1
microphone input of the AMCOM III and Diver 1’s earphone is connected to the earphone for Diver
1. All features such as diver push to talk switch and independent volume controls of the AMCOM
III remain intact. Tender uses a headset, which is plugged into the tender microphone and headset
jacks.

With the AMCOM III system you can mix 2-wire/simulcom systems, for example, Diver 1 and 2
could be Simulcom while Tender can be 2-wire (no headset - use speaker for tender). Or, one
diver can be 2-wire and one can be Simulcom. Just remember if any one person is on two-wire
you must use the push to talk (PTT) for that diver to hear or for the tender to talk.

Note: the PTT switch overrides diver conversations, (see operating guide for details).

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.

27
 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 2832-202 7.2

INPUT AMPLIFIER CIRCUIT - U1, U2, and U3, are differential input amplifiers, which accept
dynamic microphone and Pre-Amplifier Microphone, level signals (0.1 to 50mv.) and amplify them.
Signals common to both inputs are rejected. C common mode rejection (CMR) is 40db.

MIXER – U6-A mixes all divers microphone inputs. U6-B mixes tender, divers and FDW signals.

BUFFER – U6-C is a unity gain, it is used to buffer the FDW input signal.

TAPE RECORDER – U6-D is amplifier circuit to drive the taper recorder transformer.

FILTER – U7 is band pass filter. U7-A is first filter for tender output and U7-B is second for diver
output.

AUDIO POWER AMPLIFIERS – U9 and U10 are audio power amplifier integrated circuits
connected in a bridge configuration. The output "floats" at approximately 6 volts and should never
be connected to ground. The amplified audio output signal is directed to Diver or Tender through
relays K1, K2 K3, and K4.

PRE-AMP MIC DETECTION – U5 is voltage comparator IC, the circuit detect the microphone
resistance, then attenuate the diver signal through Q7, Q8, and Q9

MUTE CIRCUIT – U8 is used for mute circuit which reduces the clicking noise when depressing
PTT switch.

BATTERY VOLTAGE SENSES CIRCUIT – U11 is used to electronically sense the battery
voltage. Controls the panel LED (battery condition indicator) that indicates operational status:
Good battery voltage - steady green light
Low battery - blinking green light
Below reliable operational range – steady red light

RELAYS Circuit – The fife relays K1,K2,K3,K4, and K5 are activated through PTT switches.
K1 relay cut the Panel Speaker and Panel Microphone, when Tender PTT Jack is activated by
Hand Held PTT Microphone Jack.
K2 relay switch Tender Earphone Jacks from Output to Input, when activating PTT All Divers
Switch or Hand Held PTT Microphone Jack.
K3 relay switch Diver 1 Microphone Jacks from Input to Output, when activating PTT All Divers
Switch or Diver 2 Cross Talk switch.
K4 relay switch Diver 2 Microphone Jacks from Input to Output, when activating PTT All Divers
Switch or Diver 1 Cross Talk switch.

28
 THEORY OF OPERATION

AUDIO OUTPUT VOLUME CONTROLS 7.3

Microphone Volume Control

The output of each INPUT AMPLIFIER CIRCUIT is attenuated through microphone volume control
for tender and each diver circuit. Each individual microphone signal can be adjusted before going
to mixer U6-A and U6-B.

Earphone Volume Control

The output of the first filter circuit U7-A is attenuated through tender earphone volume control
before signal go to Power Amplifier circuit.
The output of the second filter circuit U7-B is attenuated through diver earphone volume control
before signal go to Power Amplifier circuit.

BATTERY CHARGER CARD, 2324-202 7.4

The 2324-202 converts the AC power to a regulated DC voltage to operate the unit and charge the
batteries. The charger card consists of Primary and Secondary Circuits, these two separated
circuits are connected together through step down transformer.

This Charger has a high level of insulation between Primary and Secondary circuits to prevent AC
line to pass to the amplifier circuit in order to protect divers from electric shock. The Creepage
Distance and Air Clearance on the charger meet UL2601-1 Medical Electrical Equipments
requirements. The transformer is split bobbin with high insulation between primary and secondary
winding.

The primary circuit detects AC line voltage (110 or 220), then activates latching relays K1 & K2 to
select the proper transformer primary winding connections. On the primary circuit there are 2
Micro fuses F1&F2 (400mA 250 Volt) have been mounted in socket holders. The fuses are small
round cylinders mounted next to the AC cord connection, about the size of a pencil eraser. The
Fuses are a single use safety device. They interrupt the current in the event of a massive short
circuit. Consequently, a qualified technician should thoroughly investigate the cause of a blown
fuse. 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.

The Secondary Circuit receives low voltage (20V AC) from transformer secondary winding then
regulates the voltage at 14V DC. It automatically reduces the output voltage, in order to limit the
maximum output current for charging the battery. It is designed to properly charge the internal
battery without getting damage when battery is completely drained to zero. It protects batteries
from overcharge by automatically switching to float charge of 13.8 To 14.0 Volts when batteries
are fully charged. The secondary circuit provides low current to power front panel LED which
indicates AC power is applied to unit.

There is a fuse F3 in the secondary circuit located next to J2. If accidental

reversing of internal battery terminals occurs, the fuse will blow to protect the
electronic circuits and wires from damage. F3 fuse is replaceable with 3.15A-250V
Slow Blow Micro Fuse.

29
 THEORY OF OPERATION

OPTION /26DSP2 HELIUM SPEECH UNSCRAMBLER 7.5

The New Amron DSP2 is the third generation of Helium Speech Unscramblers (HSU). The
unique design utilizes the latest technological advancements including dual digital signal
processors. The real-time audio processing uses both frequency and time domain technologies
for optimized performance over a wide range of depths and background noise. This state of the art
digital design can accommodate a multitude of functions ranging from the correction of the diver’s
raw helium speech to normal intelligible voice levels, advance treble boost and complex noise
reduction filters (NRF).

Amron’s advanced 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. Based on the
filter level, the operator will hear a number of beeping tones from 1-4 that corresponds with the
blue LED indicators.

OPTION /28FDW WIRELESS TENDER 7.6

The wireless tender option uses a transceiver to relay audio from a remote unit to the divers. The
wireless tender is a full duplex communication for Simulcom (four-wire). Amron’s Full Duplex
(Simulcom™) Wireless Tender is designed for the top-side tender to communicate to divers with
hands-free operation and no required buttons to push.

In addition to the remote unit, there is a master transceiver inside the communicator. Both channel
selector switch (A&B) and dipswitches (located under the battery) accommodate 40 different
channels with operating frequency range 902-928MHz. Manufacture sets both wireless
communicator and wireless remote module to work on Channel A with dip-switches setting
1,1,1,1,0,0,0,0 (1 is ON). In order to change channel of operation, it is required to apply changes
to both units (communicator and remote). Manufacture recommends changing wireless channels
to be done by technician.

Changing the system operation channel will allow more than one radio to operate in the same area
without interference. In addition, this will help to avoid interference between Amron wireless
system and any other wireless device (like telephone).

The communicator master transceiver card receives divers & tender audio signal from U6B. The
master transceivers transfer the audio signal to RF then transmits it through the antenna. At the
same the master transceiver receives at different frequency the RF signal from the remote
wireless, then it feeds remote wireless audio signal to the mixer U6C. The remote wireless
receives from and transmits to the communicator master wireless transceiver.

30
 THEORY OF OPERATION

FUNCTIONAL BLOCK DIAGRAM MODEL 2830R 7.7

31
 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 with these steps, any communication
problems must be somewhere else in the system, such as umbilical, connections, speakers,
and/or microphone.

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 (input) and headset earphones to Diver 1
earphone (output). You should be able to hear yourself talk. This verifies Diver 1 circuit.
4. Move headset microphone to Diver 2, Microphone (input) and headset earphones to Diver 2
earphone (output). You should be able to hear yourself talk. This verifies Diver 2 circuit.
5. Move headset microphone to Diver 3, Microphone (input) and headset earphones to Diver 3
earphone (output). You should be able to hear yourself talk. This verifies Diver 3 circuit.
The basic Simulcom function of the diver radio has now been checked.

COMPREHENSIVE 2-WIRE & SIMULCOM CHECK 8.3

Set all volume controls at mid-scale and turn power on.

Tender Circuit Check

1. Identify headset microphone lead and headset earphone lead. Plug into dual banana jack
adapters. (The microphone plug is red.)
2. Plug headset earphone into Tender, Headset (output) and the headset microphone into
Tender, Microphone (input).
3. Turn power on, speaker off.
4. Put on headset and speak into microphone, listening for your own voice.
5. Adjust tender microphone and earphone volume, and check that controls respond and there is
adequate volume. If you can talk to yourself, then tender circuit is operating properly.

Diver 1 Downlink Check

6. Move Headset microphone plug to tender Headset jack and move headset earphone plug to
Microphone jacks, Diver 1.
7. Talk into headset while pressing Push To Talk switch. You should be able to talk to yourself
with plenty of volume as long as the “Push To Talk, all Divers” switch is depressed, repeat
using Diver-1 PTT switch. This verifies 2-wire communication from tender to Diver 1.
8. Move headset earphone plug from Microphone (input) Diver 1 to Earphone (output) Diver 1.
9. Talk into headset. There should be plenty of volume. This checks earphone output for diver 1.

32
 MAINTENANCE

COMPREHENSIVE 2-WIRE & SIMULCOM CHECK (Continued) 8.3

Diver 2 Downlink Check

10. Move Headset microphone plug to tender Headset jack and move headset earphone plug to
Microphone jacks, Diver 2.
11. Talk into headset while pressing Push To Talk switch. You should be able to talk to yourself
with plenty of volume as long as the “Push To Talk, all Divers” switch is depressed, repeat
using Diver-2 PTT switch. This verifies 2-wire communication from tender to Diver 2.
12. Move headset earphone plug from Microphone (input) Diver 2 to Earphone (output) Diver 2.
13. Talk into headset. There should be plenty of volume. This checks earphone output for diver 2,
Simulcom.

Tender’s Speaker Downlink Check

14. Unplug headset from Microphone (input) and turn Speaker on. Press Push-To-Talk switch and
talk into speaker. You should hear yourself in headset earphones.
This verifies speaker section.
15. Turn speaker off.

Diver 1 Up-link Check

16. Place headset microphone into the Diver 1 Microphone jacks (input) and the headset
earphone plug into the Tender Headset jacks (output).
17. Talk into headset. You should hear yourself in the headphones with plenty of volume.
This verifies Diver 1, Microphone (input).

Diver 2 Up-link Check

18. Move headset microphone into Microphone (input) Diver 2.
19. Talk into headset. You should hear yourself in the headphones with plenty of volume.
This verifies Diver 2 Microphone (input).

PROBLEMS AND THEIR POSSIBLE CAUSES 8.4

Unit Not Operating

Check to see that unit is turned on, (speaker and headset switch). Check that battery condition
indicator is steady green (ok). Check to see that connections are proper, correct if necessary. Use
diver radio field check procedure to determine if problem is within the unit or elsewhere within the
communication system. Check to see that the P.C. Card connectors are properly seated, there
should be no gap between the bottom of the connector housing and the connector header on the
circuit card. Check that connectors are installed correctly, (headers are not offset left or right).
Push connector down and recheck.

A great number of problems are very simple failures and can often be found by a very careful and
close inspection of the unit or system. Logical deductions and equipment familiarity can often
reduce the suspected area to just one component or circuit. Often upon examination, clues are
revealed which can also aid in locating and correcting the problem. Visual inspections should
include checking all screws for tightness, all solder joints for correctness, broken parts, corrosion,
electrolysis, foreign material, check connectors for proper insertion and alignment. Check to see
that unit is turned on, speaker on.

33
 MAINTENANCE

PROBLEMS AND THEIR POSSIBLE CAUSES (continued) 8.4

Check that battery condition is ok, (battery condition indicator). Operate from line voltage or
charge batteries, depending upon options.

Check to see that connections are proper, correct if necessary.

Check operating voltage, using a digital voltmeter or equivalent, measure the voltage across the
yellow push to talk jacks on the front panel of the unit. The voltage must be greater than 9.5 volts
D.C. for the unit to operate reliably. Normal voltage for an AC powered unit is from 11.9 to 14.4
volts D.C. Normal voltage for an A.C. Powered unit operating from the backup battery is from 10.5
to 14.4 volts, when not connected to A.C. Power.

Low Volume

Check volume control settings, adjust if desired. Check diver connections, correct if bad. Use diver
radio field check procedure. Check for low batteries.

Garbled Voice To Diver

Tender volume to diver is set too high – reduce tender microphone volume or diver earphone
volume. Divers earphones corroded or defective, replace same. Tender’s microphone (speaker)
defective or full of moisture, empty water out of speaker or replace tender headset. Check diver
communication cable and connections.

Garbled Voice To Tender

The diver volume to tender is set too high; reduce diver microphone volume or tender earphone
volume. Tender’s headset is marginal, speaker has water in it, or diver’s microphone is marginal,
damaged communication cable or connections. Substitute with known good units to determine
exact problem and correct.

Diver Cuts Out

Check for intermittent connection, substitute system components with known good units to
determine exact problem and correct fault.

Connections
Most diver communications problems are caused by bad connections. The time spent in making
good connections will result in years of good communications. All connections must be soldered to
last for any period of time. Copper wire must be tinned as a minimum, it is strongly suggested that
dual banana plugs be used for topside connections. This provides a convenient and secure
connection which will last for several years if treated with a reasonable amount of care.
All cable splices must be soldered, splices should be staggered, covered with shrink tubing
preferably shrink tubing with an adhesive sealant, and a general splice cover to protect the
connections. Potting of splices is a very good and professional approach, however not necessary
to create a reliable splice.

Push To Talk Does Not Function But Tender Hears Diver (2-Wire Mode)
Find which push to talk switch is not working (PTT All Divers, PTT-Diver 1 & PTT-Diver 2). Check
connection to tender headset microphone if used. Check battery condition indicator to be steady
green. It could be a broken wire on the switch terminals or a bad connection with PC card.

34
 MAINTENANCE

PROBLEMS AND THEIR POSSIBLE CAUSES (continued) 8.4

Diver Hears Tender But Tender Cannot Hear Diver, Or Volume Is Very Low
Check to see if diver is connected to microphone and not earphone. Check to see that volume
levels are not turned down. Inspect diver connections, hat components.

Feedback - Simulcom
Check orientation of cable wiring, earphone and microphone wire pairs should be opposing wires.
These situations may cause feedback, tender’s speaker on while headset is connected, unused
diver communications connected to system, damaged communications cable or connections,
(open or shorted wires or connections). Resistance for a new cable should be in excess of 10 Meg
ohms.
In a situation where the communication cable is damaged, reduce volume to diver as low as
possible (reduce side-tone), or go to 2-wire operation until cable can be repaired.

Feedback can be caused by leakage between the microphone and earphone wires in the umbilical
better know as a cross coupling signal between umbilical wires. Adjust the diver microphone
volume to determine which umbilical has cross coupling signal between wires. Rotate the
earphone banana plug (black) 180 degrees on the communicator as this it may stop the feedback.
We highly recommend using Amron’s CC1 communication cable that has been specially designed
and tested for use with our communicators.

Distortion
This can be caused by several conditions – microphone volumes is adjusted too high, system is
on the verge of feedback, marginal components (earphones or microphone). Check by
substitution, replace defective component. Note: when operating with a standby diver who does
not have his hat/helmet on, acoustic feedback or distortion may occur. Correct by turning his
volume down or disconnecting his communication cable (at least his microphone, which will
reduce overall system noise.).

Low Battery Indication

If battery voltage is low, charge batteries for a minimum of 24 hours to fully charge battery. Battery
will charge anytime the unit is plugged into the AC line, make sure the AC power circuit being used
is not switched off at night. The preferred method to charge the battery is with power off. The
charger circuit is designed to maintain the battery at full charge during normal operation, and
power can be left on without damage to the battery.

The battery voltage can be checked by measuring across the yellow jacks on the front panel. Turn
the unit on; if the unit is plugged into the AC line, the measurement will be the output of the battery
charger. To measure the battery voltage, disconnect the unit from the AC line.

The voltage at full charge with the charger on should be between 13.0 and 14.0 volts. With the
charger off, a fully charged battery should be between 11.75 and 12.5 volts. The battery voltage of
a discharged battery (rechargeable) is 10.0 volts; the battery should not be operated below this
point as permanent damage will occur. The rechargeable batteries used in the Amron
communicators are a gel cell design.

35
 DRAWINGS & SCHEMATICS

General 9.1

The following drawings illustrate the electrical and mechanical details of the AMCOM II Diver
Communications. The corresponding parts lists for each drawing are detailed in the parts lists
section, or are included as part of the drawing.

Revisions

As drawings are updated, information about changes is incorporated into a revision sheet. This
revision sheet appears in the manual immediately after the drawings. It lists the drawing number,
reference designator of the part or parts involved a description of the revision, and the effective
serial number of the change. With this information the technician can determine the correct
drawing for the current version, and any previous version, of the unit covered by this manual. If the
revision is applicable for all versions of the unit, it is not included in the revision notice, as the
change applies to all units.

36
 DRAWINGS & SCHEMATICS

SCHEMATIC 2830R/24 9.2

37
 DRAWINGS & SCHEMATICS

SCHEMATIC OPTION /26DSP2 9.3

38
 DRAWINGS & SCHEMATICS

SCHEMATIC OPTION 2828-FDW 9.4

39
 DRAWINGS & SCHEMATICS

SCHEMATIC 4002 OPTION 9.5

40
 DRAWINGS & SCHEMATICS

PARTS IDENTIFIER, 2832-203 9.6

41
 DRAWINGS & SCHEMATICS

PARTS IDENTIFIER, 2324-202 9.7

42
 DRAWINGS & SCHEMATICS

PARTS IDENTIFIER, FRONT PANEL MODEL 2830R/24 9.8

43
 DRAWINGS & SCHEMATICS

PARTS IDENTIFIER, OPTIONS /26DSP2, /28, -4002 9.9

44
 PARTS LIST

GENERAL 10.1

The following parts lists include all mechanical and electrical parts. The following information will
be useful in interpreting data which is not self-explanatory.

Revisions

The parts lists in this manual are for the current model of diver communicator as of the printing
date. If a different part was used in a previous build, details of the parts change are included in the
revision listing sheet. This will enable you to determine the correct replacement part. If the new
part is the recommended replacement part for all units, the old part is not listed in the revision
listing.

To Order Replacement Parts Contact:

Amron international Diving Supply, Inc.

1380 Aspen Way, Vista, California, 92081 U.S.A.
Telephone: (760) 208-6500 Fax: (760) 599-3857
Email: sales@amronintl.com
Web: www.amronintl.com

When ordering replacement parts, you should give as much information as possible to enable us
to supply the correct part. This information should include the part number, description, reference
designator, value, radio model number, and serial number. Failure to provide sufficient information
may hinder our ability to fill your parts orders promptly and correctly.

45
 PARTS LIST

AMCOM III RACKMOUNT MODEL 2830R/24 10.2

Reference Part Number Description
N/S ................................2832-203-03...............................PC CARD ASSEMBLY AMCOM III
N/S ................................2830R-400 .................................AMCOM III RM FRONT PANEL ASSBY
N/S ................................2825R-500D...............................CHASSIS RACK MOUNT ASSEMBLY
N/S ................................2405-28 ......................................MICROPHONE PUSH TO TALK
N/S ................................2890-04 ......................................BATTERY RECHARGE 6V GEL 5AMP
N/S ................................2825R-002 .................................LID RACK MOUNT TOP AND BOTTOM
N/S ................................MS-3106A-28-16P .....................MS CONN CABLE 20 PIN M
N/S ................................MS-3057-16A .............................MS CABLE CLAMP 24/28 SHELLS
N/S ................................2830R/MANUAL.........................MANUAL FOR 2830R DSP2
N/S ................................8-32X1/4SSPHP ........................SCREW 8-32 1/4IN SS PH PHILL
N/S ................................8-32X1/2SSPHP ........................SCREW 8-32 1/2IN SS PH PHILL
N/S ................................8-32X3/8SSPHP ........................SCREW 8-32 3/8IN SS PH PHILL
N/S ................................8ISW...........................................WASHER NO 8 INTERNAL STAR S/S
N/S ................................3500 ...........................................CABLE TIE NY 3/32IN X 3.5IN
N/S ................................10-32X1/2SSPHP ......................SCREW 10-32X1/2IN SS PH PL
N/S ................................10LWSSS...................................WASHER SPLIT LOCK NO10 S/S
2 ....................................492 .............................................HANDLE ROUND 1.5X5.5X5/16
N/S ................................TAT-1/8 ......................................HEAT SHRINK TUBING 1/8IN BLACK
N/S ................................P-2392........................................CORD AC EURO 3 COND (7421.072)

AMCOM III RACK MOUNT, UNSCRAMBLER 2830R/24/26DSP2 10.3

Reference Part Number Description
N/S ................................2832-203-03...............................PC CARD ASSEMBLY AMCOM III
N/S ................................2830R/26-400M-DSP2...............AMCOM III FRNT PANEL R/M /26
N/S ................................2825R-500D...............................CHASSIS RACK MOUNT ASSEMBLY
N/S ................................2826-DSP2-200 .........................PC CARD ASSEMBLY UNSCRAMBLER
N/S ................................2405-28 ......................................MICROPHONE PUSH TO TALK
N/S ................................2890-04 ......................................BATTERY RECHARGE 6V GEL 5AMP
N/S ................................2825R-002 .................................LID RACK MOUNT TOP AND BOTTOM
N/S ................................MS-3106A-28-16P .....................MS CONN CABLE20 PIN M
N/S ................................MS-3057-16A .............................MS CABLE CLAMP 24/28 SHELLS
N/S ................................2830R/MANUAL.........................MANUAL FOR 2830R DSP2
N/S ................................8-32X1/4SSPHP ........................SCREW 8-32 1/4IN SS PH PHILL
N/S ................................8-32X1/2SSPHP ........................SCREW 8-32 1/2IN SS PH PHILL
N/S ................................8-32X3/8SSPHP ........................SCREW 8-32 3/8IN SS PH PHILL
N/S ................................8ISW...........................................WASHER NO 8 INTERNAL STAR S/S
N/S ................................3500 ...........................................CABLE TIE NY 3/32IN X 3.5IN
N/S ................................10-32X1/2SSPHP ......................SCREW 10-32X1/2IN SS PH PL
N/S ................................10LWSSS...................................WASHER SPLIT LOCK NO10 S/S
2 ....................................492 .............................................HANDLE ROUND 1.5X5.5X5/16
N/S ................................TAT-1/8 ......................................HEAT SHRINK TUBING 1/8IN BLACK
N/S ................................P-2392........................................CORD AC EURO 3 COND (7421.072)

46
 PARTS LIST

AMCOM III MODEL – 4002 OPTION 10.4

Reference Part Number Description

N/S ................................1N4003.......................................DIODE1A 200V

N/S ................................29MF250-1K ..............................RESISTOR 1K 1% 1/4W
15 ..................................LEDGREEN ...............................LEDGREEN BRITE
16 ..................................LEDHOLDER-BLK.25 ................MOUNTING CLIP FOR 5MM LED
20 ..................................273-068 ......................................SONALERT 12 VDC 2900 HZ
N/S ................................MS-3102A-14S-2S .....................MS CONN BULKHEAD 4PIN F
N/S ................................4-40X3/8SSPHP ........................SCREW 4-40 3/8IN SS PH PHILL
N/S ................................4NUTSSL ...................................NUT LOCKING 4-40 S/S
N/S ................................TAT-1/8 ......................................HEAT SHRINK TUBING 1/8IN BLACK

SUB ASSEMBLY 2830R-400, FRONT PANEL ASSEMBLY 10.5

Reference Part Number Description
1 ....................................2830R/24-001 ............................PANEL FRONT 2830R/24-001
N/S ................................2825R-006 .................................PANEL FRONT SUB-RACK MOUNT
3 ....................................SA818.........................................SPEAKER 8 OHM 15 WATT
4 ....................................SW-201 ......................................SWITCH TOGGLE DPDT
5 ....................................SW-208 ......................................SWITCH TOGGLE DPDT-MOM.
23 ..................................SWB-0001..................................BOOT TOGGLE SOFT GRAY
13 ..................................14002B.......................................5-WAY BINDING POST (BLACK)
14 ..................................14002R.......................................5-WAY BINDING POST (RED)
7 ....................................91A1AB24B15............................POTENTIOMETER 10K LINEAR
N/S ................................M-2786 .......................................NUT A/B POTS P/N 34602
N/S ................................3/8ISW........................................WASHER, 3/8 INTERNAL STAR
10 ..................................1498-103 ....................................JACK BANANA BLACK
11 ..................................1498-102 ....................................JACK BANANA RED
12 ..................................1498-107 ....................................JACK BANANA YELLOW
9 ....................................KLN-500B-1/4 ............................KNOB BLACK AL .5DIA .25INSHAFT
N/S ................................1/4-20X1.25HSBHC ...................SCREW 1/4-20 X 1.25IN LONG S/S
N/S ................................1/4-20NUTSSL...........................NUT NYLOK1/4-20
N/S ................................1/4FWSS....................................WASHER FLAT 1/4304 S/S
16 ..................................LEDGREEN ...............................LEDGREEN BRITE
17 ..................................LT2462-24-D15 ..........................LED BI-COLOR RED/GREEN
15 ..................................LEDHOLDER-BLK.25 ................MOUNTING CLIP FOR 5MM LED

47
 PARTS LIST

SUB ASSEMBLY 2830R/26-400M-DSP2, FRONT PANEL ASSEMBLY 10.6

Reference Part Number Description

1 ....................................2830R/24/26DSP2-001 ..............PANELFRONT 2830R/24/26-001
N/S ................................2825R-006 .................................PANELFRONT SUB-RACK MOUNT
3 ....................................SA818.........................................SPEAKER 8 OHM 15 WATT
4 ....................................SW-201 ......................................SWITCH TOGGLE DPDT
5 ....................................SW-208 ......................................SWITCH TOGGLE DPDT-MOM.
23 ..................................SWB-0001..................................BOOT TOGGLE SOFT GRAY
7 ....................................91A1AB24B15............................POTENTIOMETER 10K LINEAR
N/S ................................3/8ISW........................................WASHER, 3/8 INTERNAL STAR
N/S ................................M-2786 .......................................NUT A/B POTSP/N 34602
15 ..................................LEDHOLDER-BLK.25 ................MOUNTING CLIP FOR 5MM LED
17 ..................................LT2462-24-D15 ..........................LED BI-COLOR RED/GREEN
16 ..................................LEDGREEN ...............................LEDGREEN BRITE
11 ..................................1498-102 ....................................JACK BANANA RED
10 ..................................1498-103 ....................................JACK BANANA BLACK
12 ..................................1498-107 ....................................JACK BANANA YELLOW
13 ..................................14002B.......................................5-WAY BINDING POST (BLACK)
14 ..................................14002R.......................................5-WAY BINDING POST (RED)
9 ....................................KLN-500B-1/4 ............................KNOB BLACK AL .5DIA .25INSHAFT
N/S ................................1/4-20NUTSSL...........................NUT NYLOK1/4-20
N/S ................................1/4-20X1.25HSBHC ...................SCREW 1/4-20 X 1.25IN LONG S/S
N/S ................................1/4FWSS....................................WASHER FLAT 1/4304 S/S
N/S ................................28XXA-J2 ...................................J2 CABLE ASSY
N/S ................................28XXA-J3 ...................................J3 CABLE ASSY
N/S ................................28XXA-J4 ...................................J4 CABLE ASSY
N/S ................................28XXA-J5 ...................................J5 CABLE ASSY
N/S ................................28XXA-J6 ...................................J6 CABLE ASSY
N/S ................................08-56-0110.................................TERMINAL CRIMP
N/S ................................22-01-3037.................................CONNECTOR SHELL 3 PIN
N/S ................................43025-0800 ................................RECEPTACLE 8PIN MICRO-FIT
N/S ................................43025-2000 ................................RECEPTACLE 20PIN MICRO-FIT
N/S ................................TAT-1/8 ......................................HEAT SHRINK TUBING1/8INBLACK
N/S ................................TAT-3/16 ....................................HEAT SHRINK TUBING 3/16INBLACK
N/S ................................39-01-2040.................................RECEPTACLE 4PIN MINI-FIT
N/S ................................43030-0007 ................................CONTACT 3.0mm FEMALE SOCKET
N/S ................................39-00-0039.................................TERMINAL FEMALE CRIMPMINI-FIT
24 ..................................MRA112-A-RO ...........................SWITCH ROTARY SP2-12 POS BLACK
25 ..................................LEDBLUE-3MM..........................LED BLUE 3MM PANEL MOUNT INCL.

48
 PARTS LIST

SUB ASSEMBLY 2830R-4002-400M, FRONT PANEL ASSEMBLY 10.7

Reference Part Number Description
1 ....................................2830R-4002-001 ........................PANEL FRONT 2830R/24-4002
N/S ................................2825R-006 .................................PANEL FRONT SUB-RACK MOUNT
3 ....................................SA818.........................................SPEAKER 8 OHM 15 WATT
4 ....................................SW-201 ......................................SWITCH TOGGLE DPDT
5 ....................................SW-208 ......................................SWITCH TOGGLE DPDT-MOM.
23 ..................................SWB-0001..................................BOOT TOGGLE SOFT GRAY
11 ..................................1498-102 ....................................JACK BANANA RED
10 ..................................1498-103 ....................................JACK BANANA BLACK
12 ..................................1498-107 ....................................JACK BANANA YELLOW
13 ..................................14002B.......................................5-WAY BINDING POST (BLACK)
14 ..................................14002R.......................................5-WAY BINDING POST (RED)
7 ....................................91A1AB24B15............................POTENTIOMETER 10K LINEAR
N/S ................................3/8ISW........................................WASHER, 3/8 INTERNAL STAR
20 ..................................273-068 ......................................SONALERT 12 VDC 2900 HZ
9 ....................................KLN-500B-1/4 ............................KNOB BLACK AL .5DIA .25INSHAFT
N/S ................................M-2786 .......................................NUT A/B POTS P/N 34602
N/S ................................1/4-20NUTSSL...........................NUT NYLOK 1/4-20
N/S ................................1/4-20X1.25HSBHC ...................SCREW 1/4-20 X 1.25IN LONG S/S
N/S ................................1/4FWSS....................................WASHER FLAT 1/4304 S/S
16 ..................................LEDGREEN ...............................LEDGREEN BRITE
15 ..................................LEDHOLDER-BLK.25 ................MOUNTING CLIP FOR 5MM LED
17 ..................................LT2462-24-D15 ..........................LED BI-COLOR RED/GREEN

SUB ASSEMBLY 2825R-500D, CHASSIS & REAR PANEL ASSEMBLY 10.8

Reference Part Number Description
N/S ................................MS-3102A-28-16S .....................MS CONN BULKHEAD 20 PIN F
N/S ................................2820-004 ....................................END CAP
N/S ................................PC2823 ......................................PC-CARD BATTERY CONTACT
N/S ................................AD42ABS ...................................RIVET POP.125 DIA .328IN L AL
N/S ................................8-32X3/8KTSB ...........................SCREW KNURLED THUMB BRASS 3/8
N/S ................................8FWF..........................................WASHER FLAT FIBER NO 8
N/S ................................6-32X1/2SSPHP ........................SCREW 6-32 ½” SS PH PHIL
N/S ................................6NUTSSL ...................................NUT LOCKING 6-32 S/S
N/S ................................2825R-500M ..............................CHASSIS ASSY COMPONENTS ONLY
N/S ................................TAT-1/8 ......................................HEAT SHRINK TUBING 1/8 BLACK
N/S ................................TAT-3/16 ....................................HEAT SHRINK TUBING 3/16 BLACK
N/S ................................3500 ...........................................CABLE TIE NY 3/32IN X 3.5IN
N/S ................................39-01-2060.................................RECEPTACLE 6PIN MINI-FIT JR
N/S ................................39-00-0039.................................TERMINAL FEMALE CRIMP MINI-FIT
N/S ................................4300-0704 ..................................AC INLET SNAP-IN BLACK
N/S ................................1-480698-0.................................CONNECTOR 2 CIRCUIT PLUG
N/S ................................350550-3 ....................................CONTACT SOCKET 20-14 AWG
N/S ................................8/18-22 .......................................TERMINAL RING NO 8 STUD/18GA.
N/S ................................8NUTSSL ...................................NUT LOCKING 8-32 S/S

49
 PARTS LIST

2825R-500M, CHASSIS ASSEMBLY 10.9

Reference Part Number Description
N/S ................................2825R-003 .................................BRACKET GELL CELL BATTERY
N/S ................................2825R-004 .................................RAIL CARD SUPPORT
N/S ................................2825R-035 .................................CHASSIS RACK MOUNT WRAP AROUND
N/S ................................2825R-007 .................................BRACKET SUPPORT SIDE RAIL
N/S ................................2823-6002 ..................................CHARGER CHASSIS ASSEMBLY
N/S ................................8-32X3/8SSPHP ........................SCREW 8-32 3/8IN SS PH PHILL
N/S ................................8ISW...........................................WASHER NO 8 INTERNAL STAR S/S
N/S ................................8NUTSS .....................................NUT 8-32 S/S
N/S ................................8-32X5/8SSPHP ........................SCREW 8-32 5/8IN SS PH PHILL
N/S ................................ME161-2003...............................JACK PHONO W/NYL WSHRS NKL/BLK
N/S ................................42TM017 ....................................TRANSFORMER 25K TO 600 .2W
N/S ................................528-3520 ....................................CABLE TIE NY3/16INX 7.5IN
N/S ................................6-32X5/16SSFHP.......................SCREW 6-32 5/16IN S/S FLAT HD
N/S ................................8NUTSSL ...................................NUT LOCKING 8-32 S/S

SUB ASSEMBLY 2823-6002 INTERNAL CHARGER ASSEMBLY 10.10

Reference Part Number Description
N/S ................................2324-202 ....................................PC CARD ASSY POWER SUPPLY
N/S ................................2324-022 ....................................CHASSIS EXTERNAL CHARGER
N/S ................................6-32X2SSPHP ...........................SCREW 6-32 2IN SS PH PHILL
N/S ................................6ISW...........................................WASHER NO 6 INTERNAL STAR S/S
N/S ................................3467 ...........................................SPACER 3/4IN L X NO 6 ALUMINUM
N/S ................................6NUTSSL ...................................NUT LOCKING 8-32 S/S
N/S ................................CRLCBSR-4-01..........................SUPPORT CIRCUIT BOARD REVERSE
N/S ................................SRHR-3045................................RIVETS NAP HEAT RESISTANT
N/S ................................K4-54..........................................ISOLATION PADTO-220
N/S ................................4FWSS.......................................WASHER FLAT S/S300 SERIES

50
 PARTS LIST

2324-202 POWER SUPPLY CARD ASSEMBLY 10.11

Ref. Electrical Part Number Description
PC1 ...............................PC2324D....................................PC-CARD POWER SUPPLY/CHARGER
R1, R6 ...........................29SJ250-470K ...........................RESISTOR 470K 5% 1/4W
R2..................................29SJ250-390..............................RESISTOR 390 OHM 5% 1/4W
R3..................................29SJ250-62K .............................RESISTOR 62K 1/4W 5%
R4..................................29SJ250-3.3M............................RESISTOR 3.3M OHMS 5% 1/4W
R5..................................29MF250-249K ..........................RESISTOR 249K 1% 1/4W
R7..................................29SJ250-120K ...........................RESISTOR 120K 5% 1/4W
R8..................................29SJ250-10K .............................RESISTOR 10K OHMS 5% 1/4W
R9..................................29SJ250-100K ...........................RESISTOR 100K OHMS 5% 1/4W
R10................................29MF250-2.67K .........................RESISTOR 2.67K 1% 1/4W
R11................................29MF250-249.............................RESISTOR 249 OHM 1% 1/4W MF
R12................................RM0/X47-1WJ............................RESISTOR OXIDE0.47 OHM 1W
R13................................29MF250-1K ..............................RESISTOR 1K1% 1/4W
R14................................29SJ250-1.2K ............................RESISTOR 1.2K OHMS 5% 1/4W
R15................................29SJ250-1K ...............................RESISTOR 1K OHM 5% 1/4W
D1, D2, D5.....................1N4006.......................................DIODE 800 V 1A
D2..................................1N4749.......................................DIODE ZENER 24V 1W NOM D041
D3..................................1N5388B ....................................DIODE ZENER 200V 5W NOM CS 17
D7..................................1N5236B ....................................DIODE ZENER 7.5V MFR FAIRCHD
D8..................................BAV21 ........................................DIODE GENERAL PURPOSE 200V
D9..................................2324A-2002................................DIODE SILICON RECTIFIER 1N5392
Q1..................................TIP50..........................................TRANSISTOR NPN 400V 1A 40W
Q2, Q3, Q4 ....................MPSA42 .....................................TRANSISTOR NPN 300V GP
Q5..................................2N4403.......................................TRANSISTOR PNP 40V .5A GEN
Q6, Q7...........................551-NT2222A.............................TRANSISTOR NPN
F3 ..................................0034.6019 ..................................FUSE 3.15 AMP 250V MICRO QUICK
F1, F2 ............................0034.6611 ..................................FUSE 400 mA/250V SLOW MICRO
F1, F2, F3......................2324A-2005................................FUSE HOLDER 250V MICRO FUSE
C1..................................400V4.7UF .................................CAPACITOR 4.7UF400V
C3, C4 ...........................CK06-BX-474M ..........................CAPACITOR .47 UF 50V
K1, K2............................DS2E-SL2-DC24V .....................RELAY2 AMP MINIATRE 2 FORM C
D6..................................2324A-2001................................RECTIFIER BRIDGE IR
J1...................................350428-1 ....................................HEADER VERTICAL 2 PIN PC BOARD
J2...................................39-31-0060.................................HEADER 6 PIN MINI-FIT JR
C2, C5 ...........................ME208-25V470 ..........................CAPACITOR 470UF 25V RADIAL
C6, C7 ...........................2324A-2003................................CAPACITOR 4700UF 25V
U4..................................597-LM317T...............................I.C. LM317T
T1 ..................................4-44-6016-4H .............................TRANSFORMER 220/16V

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 PARTS LIST

28XXR-FS SPARES KIT FOR 2830R/24 10.12

Quantity Part Number Description

3 ....................................KLN-500B-1/4 ............................KNOB BLACK AL .5DIA .25IN SHAFT
2 ....................................1498-102 ....................................JACK BANANA RED
2 ....................................1498-103 ....................................JACK BANANA BLACK
2 ....................................1498-107 ....................................JACK BANANA YELLOW
4 ....................................14002B.......................................5-WAY BINDING POST (BLACK)
4 ....................................14002R.......................................5-WAY BINDING POST (RED)
2 ....................................91A1AB24B15............................POTENTIOMETER 10K LINEAR
2 ....................................M-2786 .......................................NUT A/B POTS P/N 34602
2 ....................................3/8ISW........................................WASHER, 3/8 INTERNAL STAR
2 ....................................SW-201 ......................................SWITCH TOGGLE DPDT
3 ....................................SW-208 ......................................SWITCH TOGGLE DPDT-MOM.
1 ....................................LEDGREEN ...............................LED GREEN BRITE
2 ....................................0034.6019 ..................................FUSE 3.15A/250V MICRO QUICK
2 ....................................0034.6611 ..................................FUSE 400mA/250V SLOW MICRO
2 ....................................LEDHOLDER-BLK.25 ................MOUNTING CLIP FOR 5MM LED
1 ....................................LT2462-24-D15 ..........................LED BI-COLOR RED/GREEN

OPTIONAL – PC CARD ASSEMBLY SPARES 10.13

Reference Part Number Description

N/S ................................2832-203-03...............................AMPLIFIER CARD ASSEMBLY

N/S ................................2823-6002 ..................................CHARGER CHASSIS ASSEMBLY
N/S ................................2826-200DSP2...........................HELIUM UNSCRAMMBLER CARD ASSY

52