GE 900 MHz User manual

Installation & Operation Guide
Reference Manual
MDS 05-2708A01, Rev. F
MDS TransNET 900™
MDS TransNET 2400™
Spread Spectrum
Data Transceiver
Including supplemental data for Board-Only units
MARCH 2013

Quick-Start instructions for this product are contained
in publication 05-4481A01.
All GE MDS manuals are available online at
www.gemds.com

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual i
CONTENTS
1.0 ABOUT THIS MANUAL............................................... 1
2.0 PRODUCT DESCRIPTION ......................................... 1
2.1 Transceiver Features ......................................................1
2.2 Model Number Codes .....................................................2
2.3 Spread Spectrum Radios—How Are They Different? .....2
2.4 Typical Applications ........................................................2
Multiple Address Systems (MAS)......................................2
Point-to-Point System........................................................3
Adding a Tail-End Link to an Existing Network..................3
Extending a TransNET Network with a Repeater..............4
2.5 Accessories .....................................................................5
3.0 INSTALLATION PLANNING ........................................ 6
3.1 General Requirements ....................................................6
3.2 Site Selection ..................................................................6
Terrain and Signal Strength...............................................7
Conducting a Site Survey..................................................7
3.3 A Word About Radio Interference ...................................8
3.4 Antenna & Feedline Selection .........................................9
Antennas ...........................................................................9
Feedlines...........................................................................10
Antenna System Ground...................................................11
3.5 How Much Output Power Can be Used? ........................12
4.0 INSTALLATION............................................................ 14
4.1 Transceiver Installation ...................................................14
4.2 Configuring Multiple Remote Units .................................18
4.3 Tail-End Links ..................................................................18
4.4 Configuring a Network for Extensions .............................19
5.0 OPERATION................................................................ 19

ii MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
5.1 Initial Start-up .................................................................19
5.2 Performance Optimization ..............................................20
Antenna Aiming.................................................................20
Antenna SWR Check........................................................21
Data Buffer Setting—Modbus Protocol.............................21
Hoptime Setting ................................................................21
TotalFlow™ Protocol at 9600 with Sleep Mode ................21
Operation at 115200 bps...................................................21
Baud Rate Setting.............................................................22
Radio Interference Checks ...............................................22
6.0 RADIO PROGRAMMING .............................................22
6.1 Radio Programming Methods .........................................22
Terminal Interface .............................................................22
PC-Based Configuration Tool............................................22
6.2 User Commands ............................................................23
Entering Commands.........................................................23
6.3 Detailed Command Descriptions ....................................28
ADDR [1–65000]...............................................................29
Network Address
AMASK [0000 0000–FFFF FFFF].....................................29
Alarm Mask
AT [ON, OFF]....................................................................29
Hayes-Compatible AT Command Support
ASENSE [HI/LO]...............................................................29
Alarm Output Sense
BAUD [xxxxx abc].............................................................29
Data Interface Port Baud Rate
BAND [A, B, C]..................................................................30
Select Sub-Band (Normally used for 2.4 GHz units)
BUFF [ON, OFF]...............................................................30
Data Buffer Mode
CODE [NONE, 1…255].....................................................31
Security Code
CSADDR [1–65000, NONE] .............................................31
Clock-Synchronizing Master Address
CTS [0–255]......................................................................31
Clear-to-Send Delay

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual iii
CTSHOLD [0–60000] ........................................................32
Clear-to-Send Hold Time
DEVICE [DCE, CTS KEY]................................................32
Radio-MODEM Behavior
DLINK [xxxxx/ON/OFF] .....................................................32
InSite Diagnostics Link Support
DKEY.................................................................................33
Turn Off Radio Transmitter‘s Test Signal
DTYPE [NODE/ROOT]......................................................33
Network Diagnostics Mode
FEC [ON, OFF]..................................................................33
Forward Error Correction
HOPTIME [7, 28]...............................................................34
Radio Transmitter Hop Timing
INIT....................................................................................34
Initialize; Restore to Factory Defaults
HREV ................................................................................35
Hardware Revision
KEY ...................................................................................35
Turn On Radio Transmitter Test Signal
LED [ON, OFF]..................................................................36
Enable/Disable PCB LEDs
LPM [1, 0]..........................................................................36
Low-Power Mode—Masters Only
LPMHOLD [0–1000]..........................................................36
Low-Power Mode Sleep Time
MODE [M, R, X].................................................................36
Radio Operating Mode
MRSSI [NONE, –40...–90].................................................37
Minimum RSSI for Mobile Operation
OT [ON, OFF]....................................................................37
Output Trigger
OWM [xxxxx] .....................................................................37
“Owner’s Message”
OWN [xxxxx]......................................................................37
“Owner’s Name”
PORT [RS232, RS485]......................................................37
Data Interface Port Signaling Standard
PWR [20–30].....................................................................38
Radio Transmitter Power Level

iv MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
REPEAT [0–10].................................................................38
Downstream Repeat Transmission Count
RETRY [0–10]...................................................................38
Upstream Repeat Transmission Count
RSSI..................................................................................38
Received Signal Strength Indicator
RTU [ON, OFF, 0-80]........................................................39
Remote Terminal Unit Simulator
RX [xxxx]...........................................................................39
Radio Receive Test Frequency
RXD [0–255] .....................................................................39
RXD Delay
RXTOT [NONE, 0–1440] ..................................................40
Receive Data Timeout-Timer
SAF [ON, OFF] .................................................................40
Store-and-Forward Services Support
SETUP..............................................................................40
Setup Radio Test
SER...................................................................................40
Radio Serial Number
SHOW CON......................................................................41
Show Virtual Connection Status
SHOW PWR .....................................................................41
Show Measured RF Transmit Power
SHOW SYNC....................................................................41
Show Clock-Synchronization Master Ntwk Address
SKIP [NONE, 1...8] ...........................................................41
Skip Radio Operating Zones
SLEEP [ON, OFF].............................................................42
Transceiver Sleep—Remotes Only
SREV................................................................................42
Firmware Revision Level
STAT .................................................................................43
Alarm Status
TEMP................................................................................43
Radio’s Internal Temperature
TX [xxxx]...........................................................................43
Radio Transmit Test Frequency
UNIT [10000–65000].........................................................43
Unit Address

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual v
XADDR [0–31]...................................................................44
Extended Address
XMAP [00000000-FFFFFFFF] ..........................................44
Map of Extension Addresses
XPRI [0–31].......................................................................44
Primary Extended Address
XRSSI [NONE, –40...–120] ...............................................44
Extension RSSI Level
ZONE CLEAR ...................................................................44
Clear Zone Statistics Log
ZONE DATA ......................................................................44
Read Zone Statistics Log
7.0 TROUBLESHOOTING..................................................45
7.1 LED Indicators ................................................................46
7.2 Alarm Codes ...................................................................46
Checking for Alarms—STAT command.............................46
Major Alarms versus Minor Alarms ...................................46
Alarm Code Definitions......................................................47
7.3 Troubleshooting Chart ....................................................48
7.4 Performing Network-Wide Remote Diagnostics ..............49
7.5 Internal Fuse Replacement .............................................50
8.0 RADIO FIRMWARE UPGRADES.................................51
8.1 Obtaining New Firmware ................................................51
Saving a Web-Site Firmware File Onto Your PC...............51
8.2 Installing Firmware Into Your Radio ................................51
9.0 OPERATING PRINCIPLES AND CONFIGURATION...52
9.1 SAF Operation with Extension Radios ............................52
Simple Extended SAF Network.........................................52
Extended SAF Network.....................................................53
Retransmission and ARQ Operation.................................53
SAF Configuration Example..............................................53
9.2 Synchronizing Network Units ..........................................54
Synchronization Messages ...............................................55
9.3 Using AT Commands ......................................................55
9.4 Configuration Parameters for S&F Services ...................57

vi MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
9.5 Using the Radio’s Sleep Mode (Remote Units Only) ......59
Sleep Mode Example........................................................ 60
9.6 Low-Power Mode (LPM)—Master Enabled ....................60
Setup Commands ............................................................. 60
Reading RSSI & Other Parameters w/LPM Enabled........ 61
Power Consumption by HOPTIME and SAF Settings ......61
9.7 Low-Power Mode versus Remote’s Sleep Mode ............ 62
9.8 Mobile Operation Support .............................................. 62
Introduction....................................................................... 62
Operational Influences—Hoptime & SAF.......................... 63
9.9 MIRRORED BITS™ Protocol Support ........................... 63
9.10 Seamless Mode Emulation .......................................... 63
9.11 Full-Duplex Emulation ................................................... 63
9.12 Co-Located and Close-Proximity Masters .................... 63
Master Station Configuration............................................. 64
Antenna System for Co-Located Master Stations............. 64
9.13 Security ........................................................................ 65
10.0 TECHNICAL REFERENCE.......................................66
10.1 Product Specifications—900 MHz ................................ 66
10.2 Product Specifications—2.4 GHz ................................. 67
10.3 Diagnostic Interface Connections (RJ-11) .................... 69
10.4 Data Interface Connections (DB-9F) ............................ 69
Pin Descriptions—RS/EIA-232 Mode ............................... 70
Pin Descriptions—RS/EIA-422/485 Mode ........................ 71
10.5 Board-Only Supplemental Data .................................... 72
Product Differences—Board-only vs. Standard ................ 72
Unit Dimensions................................................................ 72
Mounting Requirements.................................................... 73
10.6 User Configurable I/O Connections .............................. 73
Using the I/O Points with InSite™ NMS Software............. 75
Application Example—Digital I/O at a Remote ................. 75
10.7 dBm-Watts-Volts Conversion Chart .............................. 76
Copyright Notice
This manual and all software described herein are Copyright 2013 by GE MDS, LLC. All rights
reserved, including the right to correct any errors and omissions in this manual.

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual vii
Quality Policy Statement
Our employees are committed to understanding and exceeding our customer’s needs and expec-
tations.
• We appreciate our customers’ patronage. They are our business.
• We promise to serve them and anticipate their needs.
• We arecommitted toproviding solutionsthat arecost effective,innovative andreliable,
with consistently high levels of quality.
Wearecommitted tothe continuousimprovementofallof oursystemsandprocesses, to improve
product quality and increase customer satisfaction.
RF Exposure Notice
RF Safety Notice (English and French)
Concentrated energy from a directional antenna may pose a health
hazard to humans. Do not allow people to come closer to the antenna
than the distances listed in the table below when the transmitter is
operating. More information on RF exposure can be found online at
the following website: www.fcc.gov/oet/info/documents/bulletins.
Concentré d'énergie à partir d'une antenne directionnelle peut poser
un risque pour la santé humaine. Ne pas permettre aux gens de se rap-
procher de l'antenne que les distances indiquées dans le tableau
ci-dessous lorsque l'émetteur est en marche. Plus d'informations sur
l'exposition aux RF peut être trouvé en ligne à l'adresse suivante:
www.fcc.gov/oet/info/documents/bulletins.
ISO 9001 Registration
Microwave Data Systems adheres to the internationally-accepted ISO 9001 quality system stan-
dard.
UL/CSA Notice
The MDS TransNET 900 is available for use in Class I, Division 2, Groups A, B, C & D Haz-
ardous Locations. Such locations are defined in Article 500 of the National Fire Protection Asso-
ciation (NFPA) publication NFPA 70, otherwise known as the National Electrical Code.
(Approval of the MDS TransNET 2400 is pending as of August 2006.)
Professional installation required. The radio equipment described in this guide
emits radio frequency energy. Although the power level is low, the concentrated
energy from a directional antenna may pose a health hazard. Do not allow people
to come closer than 23 cm (9 inches) to the antenna when the transmitter is oper-
ating in indoor or outdoor environments in the 900 MHz band or 11.2 cm (4.4
inches) in the 2400 MHz band. More information on RF exposure is available on
the Internet at www.fcc.gov/oet/info/documents/bulletins.
Minimum RF Safety Distance
Safety Distance (900 MHz) 23 cm
Safety Distance (2.4 GHz) 11.2 cm
RF EXPOSURE
RF Exposure
l'exposition aux RF

viii MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
The transceiver has been recognized for use in these hazardous locations by two independent
agencies —UnderwritersLaboratories (UL) and the Canadian Standards Association (CSA). The
UL certification for the transceiver is as a Recognized Component for use in these hazardous
locations, in accordance with UL Standard 1604, UL508. The CSA Certification is in accordance
with CSA STD C22.2 No. 213-M1987.
UL/CSA Conditions of Approval: The transceiver is not acceptable as a stand-alone unit for use
in the hazardous locations described above. It must either be mounted within another piece of
equipment which is certified for hazardous locations, or installed within guidelines, or conditions
of approval, as set forth by the approving agencies. These conditions of approval are as follows:
1. The transceiver must be mounted within a separate enclosure which is suitable for the
intended application.
2. The coaxial antenna cable, power input cable and interface cables must be routed through
conduit in accordance with Division 2 wiring methods as specified in the National Electrical
Code, Article 501.4(B).
3. The transceiver must be used within its Recognized “Ratings”.
4. Installation, operation and maintenance of the transceiver should be in accordance with the
transceiver's installation manual, and the National Electrical Code.
5. Tampering or replacement with non-factory components may adversely affect the safe use of
the transceiver in hazardous locations, and may void the approval.
6. A power connector with screw-type retaining screws as supplied by MDS must be used.
When installed in a Class I, Div. 2, Groups A, B, C or D hazardous location, observe the fol-
lowing: WARNING —EXPLOSION HAZARD Do not disconnect equipment unless power
has been switched off or the area is know to be non-hazardous.
Refer to Articles 500 through 502 of the National Electrical Code (NFPA 70) for further infor-
mation on hazardous locations and approved Division 2 wiring methods.
FCC Part 15 Approval Notice
The products described comply with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired opera-
tion. This device is specifically designed to be used under Section 15.247 of the FCC Rules and
Regulations. Any unauthorized modification or changes to this device without the express
approval of the manufacturer may void the user’s authority to operate this device. Furthermore,
this device is intended to be used only when installed in accordance with the instructions outlined
in this manual. Failure to comply with these instructions may void the user’s authority to operate
this device.
Industry Canada Notice
This Class A digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe A est conforme à la norme NMB-003 du Canada.
Servicing Precautions
Whenservicing energizedequipment, besure towearappropriate PersonalProtective Equipment
(PPE). During internal service, situations could arise where objects accidentally contact or short
circuit components and the appropriate PPE would alleviate or decrease the severity of potential
injury. When servicing radios, all workplace regulations and other applicable standards for live
electrical work should be followed to ensure personal safety. All service must be performed by
qualified personnel.
Manual Revision and Accuracy
While every reasonable effort has been made to ensure the accuracy of this manual, product
improvements may result in minor differences between the manual and the product shipped to
you. If you have additional questions or need an exact specification for a product, please contact
our Technical Services team using the information at the back of this guide. In addition, manual
updates can often be found online at www.gemds.com.

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual ix
ESD Notice
To prevent malfunction or damage to this radio, which may be caused by Electro-
static Discharge (ESD), the radio should be properly grounded by connection to a
single-point ground that includes the unit’s chassis and antenna system. In addition,
the installer or operator must observe proper ESD precautions, such as touching a
grounded bare metal object to dissipate body charge, prior to connecting or discon-
necting cables or performing any other service work.
Environmental Information
The manufacture of this equipment has required the extraction and use of natural
resources. Improper disposal may contaminate the environment and present a health
risk due to hazardous substances contained within. To avoid dissemination of these
substances into our environment, and to limit the demand on natural resources, we
encourage you to use the appropriate recycling systems for disposal. These systems
will reuse or recycle most of the materials found in this equipment in a sound way.
Please contact your factory representative for more information on the proper dis-
posal of this equipment.
Battery Disposal—Thisproduct maycontainabattery.Batteries mustbedisposed ofproperly,
and may not be disposed of as unsorted municipal waste in the European Union. See the product
documentation for specific battery information. Batteries are marked with a symbol, which may
include lettering to indicate cadmium (Cd), lead (Pb), or mercury (Hg). For proper recycling
return the battery to your supplier or to a designated collection point.
Product Test Data Sheets
Test Data Sheets showing the original factory test results for this unit are available upon request
from the GE MDS Quality Leader. Contact the factory using the information at the back of this
manual. Serial numbers must be provided for each product where a Test Data Sheet is required.

x MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual 1
1.0 ABOUT THIS MANUAL
This manual presents installation and operating instructions of the
MDS TransNET 900™ and MDS TransNET 2400™ transceivers for use by
a professional installer. This person is expected to install, operate, and
perform basic system maintenance on the described radio. Following instal-
lation, we suggest keeping this manual near the equipment for future refer-
ence.
NOTE: If you have a board-only version of this product, the operating instructions in this
manual still apply, but refer also to the supplemental data at the back of this
manual (see Page 72).
2.0 PRODUCT DESCRIPTION
The transceiver, shown in Figure 1, is a spread spectrum radio designed for
license-free operation. These units employ Digital Signal Processing (DSP)
technology to provide highly-reliable long-distance communications, even in
the presence of weak signals or interference.
DSP technology also makes it possible to obtain information about radio
operation and troubleshoot problems, without going to the Remote radio site.
Using appropriate software at the Master station, diagnostic data can be
obtained on any DSP radio in the system, even while payload data is being
transmitted. (See “Performing Network-Wide Remote Diagnostics” on
Page 49.)
The transceiver is housed in a compact and rugged die-cast enclosure that
need only be protected from direct exposure to the weather. It contains a
single printed circuit board with all necessary components for radio opera-
tion. No jumper settings or manual adjustments are required to configure the
radio for operation.
2.1 Transceiver Features
Listed below are several key features of the transceiver. These are designed
to ease the installation and configuration of the radio, while retaining the
ability to make changes in the future.
• 902–928 MHz operation using the TransNET 900
Figure 1.
MDS TransNET
Series Transceiver

2 MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
• 2400–2482 MHz ISM band operation with the TransNET 2400
• User-selectable option to skip sub-bands with constant interference
• 65,000 available network addresses
• Network-wide configuration from the Master station eliminates most
trips to Remote sites
• Datatransparency ensurescompatibility with virtually all asynchronous
SCADA system RTUs
• Peak-hold RSSI averaged over eight hop cycles
• Operation at up to 115,200 bps continuous data flow
• Store-and-Forward repeater operation
• Data latency typically less than 10 ms
• Same hardware for Master or Remote configuration
• Supports RS/EIA-232 and RS/EIA-485 user interface
• Low current consumption; typically less than 3 mA in “sleep” mode
NOTE: Some radio features may not be available on all models, or limited by the op-
tions purchased, or the applicable regulatory constraints for the region in which
the radio will operate.
2.2 Model Number Codes
The radio model number is printed on the label on the end of the radio’s enclo-
sure. It provides key information about how the radio was configured when it
was shipped from the factory. This number is subject to many variations
depending on what options are installed and where (country) the product is
used. Contact the factory if you have questions on the meaning of the code.
2.3 Spread Spectrum Radios—
How Are They Different?
The main difference between a traditional (licensed) radio and the
MDS TransNET transceiver is that this unit “hops” from channel to channel
many times per second using a specific hop pattern applied to all radios in the
network. A distinct hopping pattern is provided for each of the 65,000 avail-
able network addresses, thereby minimizing the chance of interference with
other spread spectrum systems. In the USA, and some other countries, no
license is required to install and operate this type of radio system, provided
that RF power and antenna gain restrictions are observed.
2.4 Typical Applications
Multiple Address Systems (MAS)
This is the most common application of the transceiver. It consists of a central
control station (Master) and two or more associated Remote units, as shown
in Figure 2. An MAS network provides communications between a central

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual 3
host computer and remote terminal units (RTUs) or other data collection
devices. The operation of the radio system is transparent to the computer
equipment. When used in this application, the transceiver provides an excel-
lent alternative to traditional (licensed) MAS radio systems.
Invisibleplaceholder
Figure 2. Typical MAS Network
Point-to-Point System
A point-to-point configuration (Figure 3) is a simple arrangement consisting
of just two radios—a Master and a Remote. This provides a half-duplex
communications link for the transfer of data between two locations.
Invisibleplaceholder
Figure 3. Typical Point-to-Point Link
Adding a Tail-End Link to an Existing Network
A tail-end link can be used to extend the range of a traditional (licensed) MAS
system. This might be required if an outlying site is blocked from the MAS
Master station by a natural or man-made obstruction. In this arrangement, a
MDSTransNET
Remote
MDSTransNET
Remote
MDSTransNET
Master
MDSTransNET
Remote
MDSTransNET
Remote
RTU
RTU
RTU
RTU
Host System
RXD
TXD
SYNC
PWR
RXD
TXD
SYNC
PWR
RXD
TXD
SYNC
PWR
RXD
TXD
SYNC
PWR
RXD
TXD
SYNC
PWR
MDSTransNET
Master MDSTransNET Remote
Host System

4 MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
TransNET radio links the outlying Remote site into the rest of a licensed
MAS system by sending data from that site to an associated TransNET
installed at one of the licensed Remote sites (see Figure 4).
As the data from the outlying site is received at the licensed Remote site, it is
transferred to the licensed radio (via a local cable connection) and is then
transmitted to the MAS Master station in the usual manner. Additional details
for tail-end links are given in Section 4.3 (Page 18).
Invisibleplaceholder
Figure 4. Typical Tail-End Link Arrangement
Extending a TransNET Network with a Repeater
Similar to a Tail-End Link, Store-and-Forward (SAF) offers a way to physi-
cally extend the network range, but in a simple and economical manner. SAF
works by dividing a network into a vertical hierarchy of two or more
sub-networks. Extension radios (designated as MODE X) serve as single-radio
repeaters that link adjacent sub-networks, and move data from one
sub-network to the next one. Invisibleplaceholder
Figure 5. TransNET Repeater Network
PWR SYNC TXD RXD
MDSTransNET
Master
REPEATER STATION
MDS x710B
Series Radio
ENTER
ESCAPE
ACTIVE
ACTIVE
STBYALARM RXALRTXALR
STBY ALARM RXALR TXALR LINE
LINE
PWR SYNC TXD RXD
Null-Modem Cable
Remote
Radio
Remote
Radio
MDSTransNET
Remote
Master Station
SPREAD SPECTRUM LINK
TO OUTLYING SITE
OUTLYING
REMOTE SITE
MAS SYSTEM (LICENSED OR UNLICENSED) LICENSE-FREE SPREAD SPECTRUM SYSTEM
RTU
RTU RTU
MDSTransNET
Extension
MODE = X
REPEATER STATION
MDSTransNET
Remote
MODE = R
SPREAD SPECTRUM LINK
TO OUTLYING SITE
OUTLYING
REMOTE SITE
MDSTransNET
Remote
MODE = R
MDSTransNET
Remote
MODE = R
MDSTransNET
Master
MODE = M
SAF = ON
RTU
RTU RTU
RTU

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual 5
2.5 Accessories
The transceiver can be used with one or more of the accessories listed in
Table 1. Contact the factory for ordering details.
Table 1. Accessories
Accessory Description Part No.
AC Power
Adapter
Small power supply module designed for con-
tinuous service. UL approved.
Input: 120/220 Vac
Output: 12 Vdc @ 500 mA (20 Watts)
01-3682A02
2-Pin DC Power
Plug
Mates with power connector on the transceiver.
Screw terminals are provided for wires.
73-1194A39
Fuse (Internal) Fuse, 2A SMF Slo-Blo 29-1784A03
Omnidirectional
Antennas
Rugged antennas suited for use at Master
stations. Consult the factory for details.
Various;
Consult factory
900 MHz
Yagi Antennas
Rugged directional antennas suited for use at
Remote stations. Consult the factory for details.
Various;
Consult factory
2400 MHz
Antennas
Rugged directional antennas suited for use at
Remote stations.
Various;
Consult factory
900 MHz
Bandpass Filter
Antenna system filter to aid in eliminating inter-
ference from paging system transmissions.
20-2822A02
TNC-to-N
Adapter Cable
(3 ft./1 meter)
Coaxial cable used to connect the radio’s TNC
antenna connector to a Type-N style commonly
used on large-diameter coaxial cables.
97-1677A159
TNC-to-N
Adapter Cable
(6 ft./1.8 meter)
Coaxial cable used to connect the radio’s TNC
antenna connector to a Type-N style commonly
used on large-diameter coaxial cables.
97-1677A160
TNC-to-N RF
Adaptor Plug
Adapts radio’s antenna connector to Type-N
style commonly used on large-diameter coaxial
cables.
97-1677A161
RS/EIA-232
Cable
Shielded data cable fitted with DB-9 male and
DB-9 female, 6 ft./1.8 meter.
97-1971A03
RJ-11 to DB-9
Adapter Cable
For connecting a PC terminal to the transceiver
via the radio’s DIAG(nostics) connector. Used
for programming and diagnostics.
03-3246A01
Flat-Surface
Mounting
Brackets
Brackets: 2˝x 3˝plates designed to be screwed
onto the bottom of the transceiver for sur-
face-mounting the radio.
82-1753-A01
Mounting
Bracket Screws
Screws: 6-32/1/4˝with locking adhesive.
(Industry Standard MS 51957-26)
70-2620-A01
19-Inch Rail
Mounting
Brackets
Adaptor for mounting the radio in a standard
19-inch equipment rack.
Consult Factory
DIN Rail Mtg.
Brackets
Adaptor for mounting the radio in a standard
19-inch equipment rack.
03-4022A01

6 MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
3.0 INSTALLATION PLANNING
The installation of the radio is not difficult, but it does require some planning
to ensure station reliability and efficiency. This section provides tips for
selecting an appropriate site, choosing an antenna system, and reducing the
chance of harmful interference.
3.1 General Requirements
There are three main requirements for installing the radio—adequate and
stable primary power, a good antenna system, and the compatible interface
between the transceiver and the data device.
Figure 6 shows a typical Remote station arrangement. Master stations are
similar, but an omni-directional antenna is normally used instead of a direc-
tional type, and a host computer replaces the data terminal equipment.
Invisibleplaceholder
Figure 6. Typical Remote Station Arrangement
3.2 Site Selection
For a successful installation, carefulthought must begiven toselecting proper
sites for the Master and Remote stations. Suitable sites should provide the
following:
• Protection from direct weather exposure
• A source of adequate and stable primary power
• Suitable entrances for antenna, interface or other required cabling
• Antenna location that provides an unobstructed transmission path in the
direction of the associated station(s)
POWER SUPPLY
13.8 VDC @ 500 mA
(6–30 Vdc)
DATATERMINAL
EQUIPMENT
MDS Transceiver
LOW-LOSS FEEDLINE
ANTENNA
SYSTEM

MDS 05-2708A01, Rev. F MDS TransNET Ref. Manual 7
These requirements can be quickly determined in most cases. A possible
exception is the last item—verifying that an unobstructed transmission path
exists. Radio signals travel primarily by line-of-sight, and obstructions
between the sending and receiving stations will affect system performance. If
you are not familiar with the effects of terrain and other obstructions on radio
transmission, the discussion below will provide helpful background.
Terrain and Signal Strength
While the 900 and 2400 MHz bands offer many advantages over VHF and
lower UHF frequencies for data transmission, they are more prone to signal
attenuation from obstructions such as terrain, foliage or buildings in the trans-
mission path.
A line-of-sight transmission path between the Master station and its associ-
ated Remote site(s) is highly desirable and provides the most reliable commu-
nications link. A line-of-sight path can often be achieved by mounting the
station antenna on a tower or other elevated structure that raises it to a level
sufficient to clear surrounding terrain and other obstructions.
The importance of a clear transmission path relates closely to the distance to
be covered by the system. If the system is to cover only a limited geographic
area, say up to 3 miles (4.8 km), then some obstructions in the communica-
tions path can usually be tolerated with minimal impact. For longer range
systems, any substantial obstruction in the communications path could
compromise the performance of the system, or block communications
entirely.
Much depends on the minimum signal strength that can be tolerated in a given
system. Fade margin for a TransNET system does not usually have to be as
conservative as a licensed system. The nature of TransNET’s
frequency-hopping algorithm reduces the impact of frequency-selective
fading.
Although the exact figure will differ from one system to another, a Received
Signal Strength Indication (RSSI) of –100 dBm will often provide acceptable
performance. A higher signal strength is generally desirable and may be
needed in special cases—for example, urban deployment.
Conducting a Site Survey
If you are in doubt about the suitability of the radio sites in your system, it is
best to evaluate them before a permanent installation is begun. This can be
done with an on-the-air test (preferred method), or indirectly, using
path-study software.
An on-the-air test is preferred because it allows you to see firsthand the
factors involved at an installation site and to directly observe the quality of
system operation. Even if a computer path study was conducted earlier, this
test should be done to verify the predicted results.
The test can be performed by first installing a radio and antenna at the
proposed Master station site and then visiting each Remote site with a trans-
ceiver and a hand-held antenna.

8 MDS TransNET Ref. Manual MDS 05-2708A01, Rev. F
With the hand-held antenna positioned near the proposed mounting spot, a
technician can check for synchronization with the Master station (shown by
a lit SYNC lamp on the front panel) and measure the reported RSSI value. If
adequate signal strength cannot be obtained, it may be necessary to mount the
station antennas higher, use higher gain antennas, or select a different site. To
prepare the equipment for an on-the-air test, follow the general installation
procedures given in this guide and become familiar with the operating
instructions given in Section 5.0, beginning on Page 19.
If time is short, and a site survey is impractical, a computer path study is a
good alternative. Factors such as terrain, distance, transmitter power, receiver
sensitivity, and other conditions are taken into account to predict the perfor-
mance of a proposed system. Contact the GE MDS Technical Services Group
for more information on path study services.
3.3 A Word About Radio Interference
The radio shares the frequency spectrum with other services and other Part 15
(unlicensed) devices in the USA. As such, near 100% error free communica-
tions may not be achieved in a given location, and some level of interference
should be expected. However, the radio’s flexible design and hopping tech-
niques should allow adequate performance as long as care is taken in
choosing station location, configuration of radio parameters and soft-
ware/protocol techniques.
In general, keep the following points in mind when setting up your commu-
nications network:
1. Systems installed in rural areas are least likely to encounter interference;
those in suburban and urban environments are more likely to be affected
by other devices operating in the license-free frequency band and by
adjacent licensed services.
2. If possible, use a directional antenna at Remote sites. Although these
antennas may be more costly than omnidirectional types, they confine the
transmission and reception pattern to a comparatively narrow lobe, which
minimizes interference to (and from) stations located outside the pattern.
3. If interference is suspected from a nearby licensed system (such as a
paging transmitter), it may be helpful to use horizontal polarization of all
antennas in the network. Because most other services use vertical
polarization in these bands, an additional 20 dB of attenuation to
interference can be achieved by using horizontal polarization.
4. Multiple transceiver systems can co-exist in proximity to each other with
only very minor interference as long as they are each assigned a unique
network address. Each network address has a different hop pattern.
Additional RF isolation can be achieved by using separate directional
antennas with as much vertical or horizontal separation as is practical.
Vertical separation of antennas is more effective per foot/meter than
horizontal.