UTC UDI-28 User manual

1
UDI-28™ User Manual
Restricted Distribution
Copy number
Customer lead number
Protected by patents no. 6125080; 6130859; 6272072
in the US and in other countries
Version: 1.42 August 2020
Dear valued customer, if you find any typo or need any clarification, please send us an email with the
relevant information (i[email protected]).

2
Disclaimers
LIABILITY DISCLAIMER
As is true of every device of diving equipment, underwater navigation systems and other underwater
equipment, the Underwater Digital Interface TM (UDI-28TM) abilities are not limitless. There are certain
limitations and restrictions of which you must be aware and certain precautions you must take when using
the UDI-28TM. Please read carefully all warnings in this document and disclaimers in each specific chapter
of the user manual.
The UDI-28TM is a computation hardware device combined with software applications that implements a
digital compass, depth measurements, navigation or tracking after acoustical signals, text messages,
gauge mode computations and alert signal communication. The UDI-28TM combines all these applications
in one unit.
The UDI-28TM is not a primary device but only an aid to send and receive text messages, to be used as
an aid in navigation or tracking after an acoustical signal, as an aid for digital compass and as an aid to
send and receive emergency signals. The UDI-28TM is not a device of life support gear. As such, it
is unlikely that you will be hurt by the instrument itself any more than you might be hurt by any other
object of similar shape, size and weight. The main danger in the use of UDI-28TM over-reliance on the
information it provides. As an electronic system it might fail spontaneously and unexpectedly due to
component, batteries or software failure. As an acoustical device based system, it can fail at any time due
to changing environmental (acoustic) conditions or internal damages of the acoustical antenna.
By purchasing or using the UDI-28TM system, it is agreed and understood that in no event will Underwater
Technologies Center Ltd (UTC) or any of their representatives be held liable for any personal injuries or
death or damages to property resulting from its operation, or for any other damages whether direct,
indirect, or consequential even if UTC has been advised of such actual or potential damages. UTC products
are authorized for use only by certified, professional divers who have maintained a sufficient level of
knowledge and high-skill proficiency through a combination of formal training, ongoing study and
experience. The user must understand that the product is liable to sudden failure.
Underwater operations are inherently dangerous, and proper safety procedures demand that you never
rely solely on just the UDI-28TM or any other single instrument, method or mechanism for human
safety or the safety of property.
REMEMBER - YOU ARE RESPONSIBLE FOR YOUR OWN SAFETY.
BOTTOM TIMER COMPUTER DISCLAIMER
As you probably know and it is true for every device of diving equipment, and other underwater equipment,
the Underwater Digital Interface TM (UDI-28TM) abilities are not limitless. There are certain limitations and
restrictions of which you must be aware and certain precautions you must take when using the UDI-28TM
as a Bottom Timer instrument. Please read carefully all warnings in this chapter and this disclaimer.
The UDI-28TM is a computation hardware device combined with software ("SOFTWARE") applications.
The Bottom Timer is implemented with software and sensors (such as digital depth sensor and related
electronic components).
The UDI-28TM is not a primary device but only an aid to calculate along the dive the time and depth. The
UDI-28TM is not a device of life support gear and should not be used as a device for life
support.

3
Bottom Timer - Time and depth are presented on the screen only for assistance, thus the diver should
take into considerations that he/she must use a diving computer or diving tables.
The main danger in the use of UDI-28TM is over reliance on the information provided by it. As lies in an
electronic system it might fail spontaneously and unexpectedly due to component, batteries, incorrect
charging or software failure. In addition the UDI-28™ also contains acoustical functions; hence, as an
acoustical device, it can fail at any time due to changing environmental (acoustic) conditions.
THE SPECIFICATIONS AND INFORMATION REGARDING THE COMPUTERIZED UNIT IN THIS MANUAL ARE
SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS
IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY
KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF
ANY PRODUCT.
NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF UTC
ARE PROVIDED “AS IS” WITH ALL FAULTS. UTC DISCLAIMS ALL WARRANTIES, EXPRESSED OR IMPLIED,
INCLUDING, WITHOUT LIMITATION, THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF DEALING, USAGE, OR TRADE
PRACTICE. IN NO EVENT SHALL UTC BE LIABLE FOR ANY DIRECT OR INDIRECT, SPECIAL,
CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INJURY, DEATH, INCLUDING, WITHOUT LIMITATION,
LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS
COMPUTERIZED UNIT, EVEN IF UTC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Underwater operations are inherently dangerous, and proper safety procedures demand that you never
rely solely on just the UDI-28TM or any other single instrument, method or mechanism for human
safety or the safety of property.
BATTERIES DISCLAIMER
Lithium Ion Batteries can catch on fire. The UDI-28™ uses Lithium Ion batteries; therefore it should NOT
be left unattended while being charged as THEY CAN CATCH ON FIRE. Proper precautions should be taken
before charging Lithium ion batteries such as having a fire extinguisher ready and placing the batteries in
a fire safe container.
THE UDI-28™ IS NOT A TOY AND SHOULD BE HANDLED WITH GREAT CARE.
Lithium Polymer Charging, Handling, Safety Information
Charging:
Lithium Polymer and Lithium Ion batteries have specific charging requirements and ONLY the chargers
rated for these cells may be used. The best charger for the UDI-28™ is provided in the pack that you
purchased. Other chargers may alter the settings and can damage cells or cause a fire due to over-voltage
charging of cells. We recommend that you use only the charger that was provided with the UDI-28.
Lithium Polymer Lithium Ion cells are a tremendous advance in battery technology for electronic devices.
However, due to the chemistry of lithium cells, there is a possibility of fire if charging is not properly done.
It is unavoidable due to the nature of lithium itself. This is no different from many things we use in daily
life –knives, kitchen cleaners, automobiles, for a few examples –which are inherently dangerous, but
which can be used very safely by adhering to simple rules and precautions.

4
Care should be taken to charge on a fireproof surface, such as brick or in a hot (warm) environment.
Do not charge the UDI-28™ when lying on an ignitable surface. If you left the UDI-28™ in a warm
environment or open to sun light, DO NOT CHARGE IT, wait until it will be cooled to a temperature of less
than 30 centigrade. Do not charge batteries near flammable items or liquids
Keep a dry fire extinguisher nearby - or a large bucket of dry sand, which is a cheap and effective
extinguisher. Do not charge inside an automobile, especially while driving.
The UDI-28™ should NEVER be left unattended while charging.
Handling Cautions:
New cells may have a high initial charge, and care must always be taken to insure that the cap of the
UDI-28™ is completely sealed. DO NOT REPLACE BATTERIES. If the batteries performances are low,
please send it to the authorized dealer for repair or replacement.
Charging cycles:
The Batteries should work in good condition for approximately 500 charging cycles. We strongly
recommend that every year you'll send the UDI-28™ for batteries test in order to measure their stability
and charging cycles. Please remember, every charging cycle shorten the batteries lifetime and there is an
ageing process with the Lithium chemistry, thus, it is important to safely dive with batteries that will enable
you to complete the dive.
COMPASS DISCLAIMER
The UDI-28 contains 3-D Magneto Impedance sensor. Combined with software, it generates the North
magnetic direction. Common sense must be used at all times when navigating, therefore it should only be
considered as aids to navigation. The UTC' policy of continuous improvement may result in changes to
product specification without prior notice. It is advised to visit www.utc-digital.com from time to time and
to download updates for new algorithm and compensation factors for this sensor.
This compass is intended for professional dive use only; It should not be used for industrial or professional
measurements. The compass' accuracy is highly dependent on the environment, for example, soft or hard
metal will highly alter the real measurement. Thus, it is advised not to use the compass in the vicinity of
any metals. UTC does not assume any responsibility for losses or claims by third parties that might arise
through the use of this compass.
PRESET LISTS DISCLAIMER - TABLE TAG
Please ensure that prior to any dive, all UDI-28™ devices and boat units, in the same network, include
the same user list and messages list. Text messaging communications will only function properly if those
lists are identical.
To ensure that the lists are identical, each UDI-28™ has a Table Tag value, which is a unique code for
each specific UDI-28™ lists.
Make sure that each UDI-28™ device and boat unit has the same Table Tag value.
The Table Tag value is displayed in the About UDI screen.

5
OPERATION, RANGE AND CONFLICT
UTC provides communication means by using different configurations. Please note that a SYSTEM that
generates two Networks (i.e., NET 1 and 2) includes at a minimum, two U28 wrist units or one wrist U28
unit and a boat units. Each U28 is capable to receive signals from up to 1000m (depending on sea and
environmental conditions). Therefore, it is critical to properly define the lists of users and messages so
two different SYSTEMS will not intersect or coincide. In order to eliminate such event, all U28 that belong
to a SYSTEM must use the same table tag value. It is advised to check if other SYSTEM already exist in
the same diving area. If by mistake, in the same area (i.e. a radius of 1000meter), two SYSTEMS operate,
then there is a chance that mistaken messages (wrong message that belong to other system or characters
that have no meaning) will be received by the end user.
License to use the Software
Notwithstanding anything herein to the contrary, the purchaser and/or user of the UDI-28TM system shall
not obtain any intellectual property right in any the UDI-28TM system or any part thereof, other than the
limited right to use it. The purchaser and/or user of the UDI-28TM system shall not have, and shall not
acquire, in any way, any intellectual property right in the UDI-28TM system. The UDI-28TM system shall
not be deemed to have been produced as work for hire and any intellectual property right with respect
thereto shall remain exclusively with UTC. For the purpose hereof, intellectual property includes, inter
alia, any property in and rights under copyright, patents, conceptual solutions and inventions (whether
patentable or not), circuit layout rights, design rights, designs, database rights, trade names, trademarks,
service marks, methodologies, ideas, processes, methods, tools and know-how, and/or any other types of
intellectual property rights. The purchaser and/or user of the UDI-28TM system may not and shall not
permit, abet or aid others to translate, reverse engineer, decompile, disassemble, update or modify all or
any part of the UDI-28TM system.

6
Contents
Introduction ............................................................................................................................................................ 8
Safety ..................................................................................................................................................................... 9
Before every dive ................................................................................................................................. 9
UDI-28™ unit........................................................................................................................................................ 10
Unit Description ...................................................................................................................................10
Using the quick connector .....................................................................................................................11
Charging the UDI-28............................................................................................................................11
Connecting the UDI-28™ to the PC ........................................................................................................12
Using the UDI-28 .................................................................................................................................................. 13
Turning UDI-28™ On and Off ................................................................................................................13
Scrolling the menus..........................................................................................................................13
UDI-28™ main menu ........................................................................................................................................... 14
Setting up the UDI-28™ ...................................................................................................................................... 15
Bottom timer ..................................................................................................................................16
PC Connection ................................................................................................................................16
Network Setup................................................................................................................................17
Transmission power ........................................................................................................................18
UDI-28™ Setup...............................................................................................................................18
Clock .........................................................................................................................................18
AUDIO SETUP ............................................................................................................................18
LED Control................................................................................................................................19
OLED Contrast............................................................................................................................19
Units .........................................................................................................................................19
About UDI-28.............................................................................................................................19
Revert to factory settings: ...........................................................................................................20
Using the Bottom Timer....................................................................................................................................... 21
Surface display ...................................................................................................................................21
Underwater display..............................................................................................................................21
Timer and reviewing additional data .................................................................................................22
Abnormal conditions........................................................................................................................23
Low battery................................................................................................................................23
Empty battery during dive ...........................................................................................................23
Using the Compass..............................................................................................................................23
Sending and receiving text messages....................................................................................................24
Sending a message.....................................................................................................................24
Viewing last message..................................................................................................................25
Receiving a message...................................................................................................................25
Navigation to a target..........................................................................................................................26
Navigation mode ........................................................................................................................26
Using the Navigation display ........................................................................................................27
SOS Signals ........................................................................................................................................27
Remote homing ..................................................................................................................................28
Remote SOS .......................................................................................................................................28
Mask Homing......................................................................................................................................29
Care and maintenance.........................................................................................................................29
Revert to factory setting ..................................................................................................................30
Base [boat] unit ................................................................................................................................................... 31
Active Antenna....................................................................................................................................32
Charging the UDI-28™ boat unit...........................................................................................................32
Connecting the UDI-28™ boat unit to the PC .........................................................................................32
Turning UDI-28™ boat unit On and Off .................................................................................................33
Scrolling the menus.........................................................................................................................33
UDI-28™ Boat unit main menu.............................................................................................................33
Sending and receiving text messages....................................................................................................33
Sending a message.....................................................................................................................34

7
Viewing last message..................................................................................................................35
Receiving a message...................................................................................................................35
Receiving SOS Signals .........................................................................................................................35
Remote SOS...............................................................................................................................36
Using the Compass..............................................................................................................................36
Transmit homing.................................................................................................................................38
Setting up the UDI-28 Boat Unit ...........................................................................................................38
Buddy Select ..................................................................................................................................38
Transmission power ........................................................................................................................39
UDI-28 Boat unit setup....................................................................................................................39
Clock .........................................................................................................................................39
AUDIO.......................................................................................................................................39
LED Control................................................................................................................................40
Display Contrast .........................................................................................................................40
Units .........................................................................................................................................40
About UDI-28.............................................................................................................................40
Care and maintenance.........................................................................................................................41
Revert to factory setting:.............................................................................................................41

8
Introduction
Congratulations on your purchase of the UTC –Underwater Digital Interface 28 System.
UDI-28™ is a device that contains several functions used for diver safety, communication and
computation. Throughout this manual we will use the term UDI-28™instead of Underwater Digital
Interface (UDI-28) System. UDI-28™ is a device that contains several functions that were implemented
to increase safety, enable underwater communication and reliable computation. The UDI-28™version
was derived from the celebrated UDI-14™while taking into consideration years of experience, feedback
from users, field measurements and specific requirements by professional organizations. This version
supports extended number of messages, two large networks, state of the art error corrections code that
increases communication reliability, extended range (without extending the power) for communication,
high capacity batteries, seamless connection process to other systems (for example Passive Acoustical
Diving Radar), OLED, enhanced compass, new acoustical antenna with improved performances, support
for different languages and more. The company is grateful to the so many users and organizations that
contributed for this version.
The system consists of the UDI-28™ diving unit, an optional UDI-28™ PRO boat unit with an active
antenna, and the UDI28-MANAGER PC software. Each item can be purchase separately.
The UDI-28™ contains the following functions:
Text messages communication device
SOS signal transmission and reception
Navigation unit and homing device
Dive Information
Compass
The UDI28-MANAGER PC software can be used in conjunction with only the UDI-28™ to be used to
update text message and names (users) lists and groups and to update the firmware.
The UDI-28™ text messaging system links divers through transmission of pre-set messages with ease
and reliability. Depending on environmental conditions, it is possible to receive signals from up to 1000
meters.
Upon receiving a message signal, the UDI-28™ unit sounds an audible alert and lights up to show the
message (if these features were enabled).
The SOS signal can be activated by a diver in distress, or remotely by any diver who suspects that his
buddy is in distress. Upon activation of an SOS signal, the UDI-28™ transmits information required to
locate the SOS sender.
Each UDI-28™ includes a homing device to help the diver locate other divers or the dive boat.
The UDI-28™ can be worn on the lower arm or attached to the Buoyancy Compensator (BC).
The UDI-28™ permits a diver to communicate with any other diver in the network without distractions
or potential discomforts.

9
Safety
Read and understand this user guide prior to using the UDI-28. We strongly recommend that prior to
using in in real environment you will gain experience with the device.
Pay close attention to all cautions and warnings listed. Make sure that you fully
understand the use, displays and limitations of the UDI-28™ prior to diving. Improper
use of this device may cause a diver to commit actions that could lead to serious injury
or death.
The UDI-28™ has a battery saving mode. After the UDI-28™ unit is turned on:
If no button is pressed on the UDI-28™ or 10 minutes, the UDI-28™ goes to standby, and the
screen displays the word Standby.
After 60 minutes of no activity, the UDI-28™ turns off.
The UDI-28™ unit contains a water sensor. When the UDI-28™ unit that has been turned on or is in
standby comes in contact with water, the bottom timer becomes active.
A dive is considered if the UDI-28™ is at a depth of 2 meters for at least 10 seconds.
Before every dive
To ensure your safe use of the UDI-28™ before every dive, you must check:
UDI-28™ battery is charged
The preset messages list and the users list (names) in the dive group are the same. This
means that the same table tag is same in all devices in the dive group.
The network used between you and your buddy or group.
Check communications by sending a message to your buddy and receiving a message back.

10
UDI-28™ unit
Unit Description
The UDI-28™ unit consists of the following:
1
6
5
4
3
2
7
1. Antenna
4. OLED display, plastic protector
2. Up scroll button
5. Attachment buckle
3. Down scroll button
6. Enter button
7. Emergency (SOS) button
The UDI-28™ contains the following functions:
Bottom timer
Electronic compass
Message sending/receiving
Homing device
Emergency signaling
Use of these functions is explained below.

11
Using the quick connector
A quick connector is used connect the UDI-28™ unit to a power supply or to a PC.
Attach the quick connector to the UDI-28™ as show below, ensure the contacts are dry.
1
2
1. Quick Connector
2. Connector bracket on UDI-28
Charging the UDI-28
UDI-28™ uses a rechargeable internal Li battery. This battery can be recharged only with the UDI-28™
charger.
NOTE: Read Lithium Polymer Charging, Handling, Safety Information on page 3.
WARNING: The UDI-28™ is a completely sealed unit. It may stop functioning if opened. The
warranty will be void if the unit is disassembled or the seal is broken.
Ensure that the UDI-28™ is fully charged before your dive.
Charge the battery for 12 hours prior to the first time you use the UDI-28.
To charge the UDI-28:
1. Ensure that your hands, the UDI-28™ and the charger are dry!
2. Ensure UDI-28 is "Off" and ony then connect the quick adapter to the UDI-28™
3. Connect the power charger to the quick connector.
4. Connect the power charger to a power supply. The green LED will turn on.
5. The charge is complete when the green light on the quick connector turns off.
6.If mistakenly UDI-28 is in On mode and was connected, disconnect it, power it off and then charge it.
Beacuse voltage difference between charge and operation, unit may beacome instable.
After fully charge, unit can be disconnected from the connector and turn "On".

12
NOTE: A steady or flashing red LED indicates a problem with the charger or the battery. Disconnect
the charger and repeat steps 2 to 4. If this does not resolve the problem, return the unit for
service
Connecting the UDI-28™ to the PC
You can connect the UDI-28™ to the PC to perform data transfers, using the UDI28-MANAGER
application. For information see UDI28-MANAGER Software User Manual.
To connect the UDI-28™ to the PC, turn On the UDI-28:
1. Connect the quick connector to the UDI-28
2. Connect the USB cable to the quick connector.
3. Connect the USB cable to the computer.
NOTE: Ensure that you have properly installed the UDI28-MANAGER software to be able to use this
function.
To activate the connection to the PC, you must enable this option on the UDI-28. See page
16.
4.DO NOT turn off the UDI-28 when connected to PC.

13
Using the UDI-28
Turning UDI-28™ On and Off
To turn the UDI-28™ on:
1. Press and hold the Enter button for about 5 seconds. The UTC Proprietary screen opens.
(If pushing the Enter button for a short time, a message on the screen will appear mentioning
the need for a longer push)
NOTE: The UTC Proprietary screen contains a disclaimer. Clicking on the Enter button signifies that
you accept responsibility for use of the UDI-28, and that you accept the terms of the disclaimer.
If you do not agree, please do not dive with the UDI-28™.
2. Press the Enter button again. The current settings screen opens.
3. Press the Enter button again. The setup menu opens. After a few seconds, the dive info
displays.
Standby mode:
The UDI-28™ unit goes into Standby mode after 10 minutes of inactivity on the surface.
The UDI-28™ unit goes from Standby to ‘Off’after 1 hour of inactivity on the surface.
When in Standby mode, the UDI-28™ unit instantly returns to use upon contact with water,
or when a button is pushed for 2 seconds.
To turn UDI-28™ off:
Press and hold the Enter button for about 6 seconds. The UDI-28™ turns off.
WARNING: Power cannot be turned off during a dive.
Scrolling the menus
To scroll through the menu options, press the Up or Down buttons.
To select an option, press the Enter button.

14
UDI-28™ main menu
The main UDI-28™ menu allows you to access UDI-28™ functions. The main menu flowchart is shown
below.
5. Setup
1. Messages
2. Navigation
3. Compass
Main
4. Dive Info
Use of the various functions is described in detail as follows:
Setup –see page 15
Dive Info –see page 21
Messages –see page 24
Navigation –see page 26
Compass –see page 23

15
Setting up the UDI-28™
Use the Setup menu to set up the UDI-28™ for the following features:
PC Connection –Connect to a PC for use with the UDI28-MANAGER software.
Network Setup –Set network for communication with buddy.
Trans. Power –Set the transmission power of the UDI-28™ units.
UDI-28™ Setup –Set UDI-28™ parameters –clock, audio, led, units, etc.
Main –Back to the Main menu.
The Setup menu flowchart is shown below.
5. Main
3. Trans.
power
Setup 1. PC
Connection
4. UDI Setup
2. Network
Setup
1. From the Dive Info display, double-click of the Enter button will open the Main menu.
2. Use the Up/Down buttons to scroll to Setup.
3. Press Enter to choose the selection.
To exit the Setup menu and return to the Main menu, select Main, and press Enter.

16
Bottom timer
WARNING: the UDI-28™ works as bottom timer; it only measures the time and depth and doesn’t
function as a diving computer that calculates any Nitrogen levels. User must be aware that in
this mode of operation, there are no alerts that are related to the diving.
PC Connection
Use the PC Connection option to connect UDI-28™ to your PC and use it with the UDI28-MANAGER
application. For information see the UDI28-MANAGER Software user manual.
WARNING: Do not enter the water with the UDI-28™ when the “PC connection”is active. This will
damage your UDI-28.
NOTE: When the PC connection has not been used for 2 minutes, it becomes disabled to prevent any
damage to the UDI-28™.
To use PC Connection:
1. Connect the quick connector to the UDI-28
2. Connect the USB cable to the quick connector.
3. Connect the USB cable to the PC computer.
4. On the UDI-28™ Setup menu, select PC Connection.
5. Select Enable press
Enter to enable the
PC Connection. A PC
indication appears at
the bottom right
corner of the display
while the UDI-28™ is
connected to the PC.
PC Connection
2. Disable
1. Enable
NOTE: Communication with the UDI-28™ is done using the UDI28-MANAGER software provided with
your system. For information see the UDI28-MANAGER Software user manual.

17
Network Setup
Use this option to select User and Buddy numbers; and a network.
NOTE: You and your buddy must be properly defined on your UDI-28™ and your buddy’s UDI-28™
respectively, and you must both be on the same network to be able to communicate using the
UDI-28.
1. Select Net to define a network
to use, and press Enter.
NETWORK SETTING
1. Net
4. Setup
2. User
2. Select a network from 1 or 2,
and press Enter.
NETWORK
1. Net 1
2. Net 2
3. Select User to define the user
name/number for the UDI-28™
and press Enter.
NETWORK SETTING
2. User
1. Net
3. Buddy
4. Select a User (named or
numbered) from the 28 users,
and press Enter.
USER
2. Brad
1. User 1
3. Jen
5. Select Buddy to define your
buddy number and press
Enter.
NETWORK SETTING
3. Buddy
2. User
4. Setup
6. Select a User (named or
numbered) from up-to 28
individual users, boat, or all
users and press Enter.
This will be your default for
sending a message to.
BUDDY
4. Bob
3. Jen
5. Armin

18
Transmission power
UDI-28™has the ability to adjust the transmission power. This feature enables the diver to select from
3 transmission power levels:
Low power
Med power
High power
Working with low power level increases the battery lifetime while high power level shorten battery
lifetime.
The diver is advised to maintain a low or medium level except in extreme cases where it is important to
send communication for long range. This feature also serves for next update to identify out of range
capabilities.
Select a power level and press Enter
TRANS POWER
2.Med power
1.Low power
3.High power
UDI-28™ Setup
Use the UDI-28™ Setup menu options to set the time, volume, led and units on your UDI-28.
Clock
Use this option to set the time and date.
1. Press Enter to select a time
unit.
2. Use the Up/Down buttons to
set the appropriate value.
3. Press Enter to move to the
next time unit on the list.
4. Repeat.
5. When you have set the year
value, press Enter to return to
the UDI-28™ Setup menu.
CLOCK SETUP
20
25/03/2014
:11
AUDIO SETUP
Use this option to select an audio alert volume. Audio alerts sound when a message is received, when
the battery meets low level.
There are five levels of alert:
High
Med-High
Med
Low
Off

19
Select a ring level and press Enter
AUDIO
2 Med-High
1 High
3 Med
LED Control
Use this option to turn on or off the Green LED control which allows the LED on the UDI-28™ to blink
when there is an audible alarm or when a signal is received.
Select Enable or Disable and press
Enter.
The Default: Enable
LED CONTROL
1. Enable
2. Disable
Contrast
Use this option to select a contrast level for the OLED display. .
The contrast interval ranges from 1 (very little contrast) to 7 (high contrast).
Use the Up/Down buttons to
define a contrast value and press
Enter. Make sure there are no
strips seen on the screen.
CONTRAST
Contrast: 7
Units
Use this option to select Metric units (meters, degrees C) or Imperial units (Feet, degrees and
Fahrenheit) as your unit of measurement.
Select Imperial or Metric and press
Enter. All units displayed on the
UDI-28™ will now conform to the
unit type chosen.
UNITS
1. Imperial
2. Metric
NOTE: The temperature displays according to your units selection –When you select Feet, Fahrenheit
degrees are shown, when you select Meters, centigrade degrees are shown.
About UDI-28
Use this option to view the UDI-28™ serial number and software version installed. Use this information
when contacting UTC about your UDI-28.
In addition the About UDI screen presents the table tag value, which is a unique code for each specific
UDI-28™ list of users and messages. Make sure that every UDI-28™ device and boat unit (in the same
network) has the same Table Tag value. For more information see page 4.

20
ABOUT UDI
19:36 25/03/2014
S/N: 28-111007
Version:
UDI28_LowB_14
Tables Tag
1C56AF
Revert to factory settings:
In case you would like to revert to the original UDI-28™ factory settings, press the Up, Down and
Enter buttons simultaneously to start the UDI-28™ on. Wait for the UDI-28 to turn on and for the
message “set default” appears on the screen. All customizations and settings you have done will be
erased, and UDI-28 will turn on with the original factory settings.