MDS 4790B Original operating instructions

Installation & Operation Guide
MDS 05-2765A01, Rev. B
OCTOBER 2005
400 MHz/900 MHz
Multiple Address System
Master Station Radio
MDS 4790B/9790B

QUICK START GUIDE
1. Install and connect the antenna system to the radio (Page 11).
•Review “Antenna Installation Warning” following the Table of Contents in this manual.
• Use a high-quality gain antenna, mounted in the clear.
• Use high-quality low-loss feedline. Keep the feedline as short as possible, avoiding sharp bends.
2. Switch on the backup battery (Page 17).
• Switch is located behind removable front panel.
• If the battery is discharged, the radio must be operated on AC power for 8 hours before the backup
battery will be available for use.
3. Connect the host computer to the DATA connector on the rear panel (Page 24).
• Connect only the required pins. Do not use a straight-through cable with all pins connected.
• RS/EIA-232 cable length should not exceed 15 meters/50 feet for reliable operation.
4. Verify proper input voltage level and connect power to the radio. Set the power supply
switch(es) to ON.
•Voltage is normally marked on the rear of the power supply. See “Specifications” for voltage ranges.
•The radio can be operated in either a positive or negative ground configuration. The center pin of the
connector is not connected in the radio.
5. Observe front panel indicators for proper operation.
Invisible place holder
ACTIVE (green)—This transceiver board (A or B) is the selected unit.
STBY (yellow)—This transceiver board (A or B) is the standby unit (redundant version only).
ALARM (red)—General fault not covered by the other alarm categories (RX ALR, TX ALR, I/O ALR).
RX ALR (red)—Difficulty receiving. May be due to an antenna problem, receiver fault, or other
condition causing a low received signal level.
TX ALR (red)—Fault with the transmit circuitry.
I/O ALR (red)—The data rate or format is incompatible with the radio settings.
A
B
ACTIVE STBY ALARM RX ALR TX ALR I/O ALR
ACTIVE STBY ALARM RX ALR TX ALR I/O ALR

MDS 05-2765A01, Rev. B MDS x790B Series I/O Guide i
TABLE OF CONTENTS
1.0 INTRODUCTION.....................................................................................1
2.0 PRODUCT DESCRIPTION.....................................................................1
2.1 PC-Based Diagnostics .....................................................................2
2.2 Redundant versus Non-redundant Operation ..................................2
2.3 Applications ......................................................................................3
Basic MAS Master Station Operation ...............................................3
2.4 Repeater and Polling Remote Operation .........................................4
Simplex and Switched Carrier Operation.......................................... 6
2.5 Radio Features .................................................................................6
2.6 Model Number Codes ......................................................................7
2.7 Accessories ......................................................................................7
3.0 INSTALLATION PLANNING ....................................................................8
3.1 General Requirements .....................................................................8
Site Selection....................................................................................9
Terrain and Signal Strength ..............................................................9
On-the-Air Test ................................................................................ 10
A Word About Interference.............................................................. 10
3.2 Antenna and Feedline Selection ....................................................11
Antenna System..............................................................................11
Feedline Selection ..........................................................................11
4.0 INSTALLATION PROCEDURES ...........................................................13
4.1 Unpacking and Inspection ..............................................................13
4.2 Mounting the Radio ........................................................................13
Rack Mounting ................................................................................14
Ta b letop Mounting...........................................................................14
Remote Front Panel Mounting—Optional Configuration................. 14
4.3 Primary Power ................................................................................ 15
AC-Powered Units...........................................................................16
DC-Powered Units ..........................................................................16
4.4 Backup Battery ...............................................................................17
Location of Battery Switch ..............................................................17
Low Voltage Disconnect Feature..................................................... 18
Battery Reset Switch (SW1) ...........................................................18
Antenna Installation ........................................................................ 19
Feedline Installation ........................................................................19
4.5 Interface Wiring Connections .........................................................20
Coaxial Connectors (Type-N)—TX, Antenna, RX ...........................20
Ground Connection.........................................................................22

ii MDS x790B Series I/O Guide MDS 05-2765A01, Rev. B
Diagnostics Connector—J1 ............................................................ 22
4-Wire Audio Connector—J2 ..........................................................23
Data Connector—J3 ....................................................................... 23
Orderwire—J9.................................................................................25
Alarm Contacts—J10 ......................................................................25
4.6 Post Installation Checks .................................................................26
5.0 START-UP AND OPERATION...............................................................26
5.1 Initial Startup .................................................................................. 26
Normal Indications ..........................................................................27
Coordinating Activities by Orderwire...............................................27
Maximizing RSSI.............................................................................28
5.2 Front Panel Indicators ....................................................................28
LED Indicators ................................................................................ 28
Front Panel Display.........................................................................29
6.0 LOCAL DIAGNOSTICS & CONTROL...................................................30
6.1 PC Connection for Diagnostic Work ...............................................31
6.2 PC Command Summary Tables .....................................................33
Commands and Command Parameters..........................................33
6.3 Command Equivalents for Older Transceivers ............................... 36
6.4 Detailed Command Descriptions ...................................................36
AK [16-Digit Alphanumeric String] ..................................................37
ALARM............................................................................................38
AMASK [0000 0000–FFFF FFFF]...................................................39
ASENSE [HI/LO].............................................................................40
BATT [ON/OFF]...............................................................................40
BAUD [9600 abc] ............................................................................41
BAUD [9600S].................................................................................41
CKEY [ON/OFF]..............................................................................41
CTS [0-255].....................................................................................42
DATE [mmm dd yyyy]...................................................................... 42
DECF [0–100] ................................................................................. 42
DECP [0–100].................................................................................43
DF ...................................................................................................43
DIAGLEV [OFF, 1, 2, 3]................................................................... 43
DKEY ..............................................................................................43
DP...................................................................................................43
EMP [ON/OFF]................................................................................43
HREV..............................................................................................44
IF.....................................................................................................44
INCF [1–99].....................................................................................44
INCP [1–99] .................................................................................... 44
INIT .................................................................................................44
IP.....................................................................................................45
KEY.................................................................................................45
LBC [nnnn]......................................................................................45
LOG [CLR] ...................................................................................... 46
MODEL ...........................................................................................46

MDS 05-2765A01, Rev. B MDS x790B Series I/O Guide iii
MODEM [NONE/BELL/4800B/9600B] ............................................ 46
NMASK [0000 0000–FFFF FFFF]...................................................47
OPT.................................................................................................48
OWM [xxxxx] ...................................................................................48
OWN [xxxxx] ...................................................................................48
PTT [0-255].....................................................................................48
PWR [20–37]...................................................................................49
RADIO [AUTO/A/B] .........................................................................49
REPEATER [ON/OFF] ....................................................................49
RMIS ............................................................................................... 50
RMOV .............................................................................................50
RMRD .............................................................................................50
RMST..............................................................................................50
RSSI, RSSI! .................................................................................... 50
RX [xxx]...........................................................................................51
RXLEVEL [–20 to +3]......................................................................51
RXMUTE [ON/OFF/Time in msec]..................................................51
RXPAD [ON/OFF] ...........................................................................52
RXTOT [NONE, 1-1440] .................................................................52
SCD [0-255] .................................................................................... 52
SER.................................................................................................52
SHOW [DC/PWR/CURRENT/RADIO] ............................................52
SREV ..............................................................................................53
SQU [1–10] .....................................................................................53
STANDBY [ON/OFF].......................................................................53
STAT................................................................................................54
SWC [ON/OFF] ............................................................................... 55
TEMP .............................................................................................. 55
TIME [hh:mm:ss].............................................................................55
TOT [ON/OFF, 1-255] ....................................................................56
TX [xxxx] ......................................................................................... 56
TXGAIN [ON/OFF] .......................................................................... 56
TXLEVEL [–20 to +3, AUTO] ..........................................................56
6.5 Configuration and Programming using the Front Panel .................57
Programming and Control Buttons..................................................58
Navigating Through the Front Panel Screens .................................60
Switching the Front Panel Display to Configuration Mode ..............60
Use of Control Buttons in Configuration Mode................................61
Making changes to radio functions .................................................61
6.6 Screen Descriptions .......................................................................61
Group 1—Startup Screen and Menu Directory............................... 62
Group 2—Configuration Screens....................................................62
Group 3—Diagnostic Screens ........................................................62
Group 4—Event Log .......................................................................62
7.0 PROBLEM SOLVING ............................................................................77
7.1 Front Panel LEDs ...........................................................................77
7.2 Chassis-Mounted LEDs .................................................................78
7.3 Problem Solving Using a Connected PC .......................................80

iv MDS x790B Series I/O Guide MDS 05-2765A01, Rev. B
7.4 Problem Solving Using the Front Panel Display .............................80
Event Log........................................................................................80
7.5 System Bench Testing Set-Up ........................................................ 81
8.0 REPLACING ASSEMBLIES..................................................................82
8.1 Transceiver Board and Power Supply Assemblies ......................... 82
8.2 Installation & Removal of Backup Battery (P/N 28-1575Axx) ........83
8.3 Front Panel .....................................................................................84
8.4 Operating Frequency Change Considerations ...............................85
MDS 4790—400 MHz Notch-Type Duplexers.................................85
MDS 9790—Bandpass-Type Duplexers..........................................86
MDS 4790/9790 Simplex Radios—With Antenna Switch Modules.87
MDS 4790/970—Front End Helical Coil Alignment.........................87
8.5 Testing and Removing an Internal Duplexer ...................................87
Testing.............................................................................................87
Removing the Internal Duplexer......................................................88
8.6 Testing and Removing the Antenna Switch Module ....................... 89
Testing.............................................................................................89
Removing the Antenna Switch........................................................90
8.7 Cooling Fan Maintenance .............................................................91
9.0 RADIO SOFTWARE UPGRADES ........................................................92
9.1 Obtaining New Code ......................................................................92
9.2 Preparing for Download .................................................................92
9.3 Downloading New Code—Procedure ............................................93
10.0 DIAGNOSTICS & CONTROLOF REMOTE TRANSCEIVERS............93
10.1 Diagnostics Levels .......................................................................94
Level 1—Loopback .........................................................................94
Level 2—Advanced Diagnostics .....................................................94
Level 3—Remote Maintenance.......................................................94
11.0 TECHNICAL REFERENCE.................................................................95
11.1 Technical Specifications ......................................................... 95
11.2 RF Propagation Planning .............................................................97
Fresnel Zone Clearance..................................................................97
Earth Curvature ..............................................................................98
Fade Margins .................................................................................. 99
Calculating Path Loss .....................................................................99
11.3 Formulas for System Planning ..................................................... 99
Free Space Path Loss.....................................................................99
Fresnel Zone Boundary ................................................................ 100
Theoretical Signal Strength...........................................................100
Probability of System Fading ........................................................100
11.4 dBm-Volts-watts Conversion Chart ............................................101
DATA SYNCHRONIZER MODULE ...........................................................102

MDS 05-2765A01, Rev. B MDS x790B Series I/O Guide v
Copyright Notice
This Installation and Operation Guide and all software described herein
are protected by copyright: 2005 Microwave Data Systems Inc. All
rights reserved.
Microwave Data Systems Inc. reserves its right to correct any errors and
omissions in this publication.
Antenna Installation Warning
1. All antenna installation and servicing is to be performed by
qualified technical personnel only. When servicing the antenna, or
working at distances closer than those listed below, ensure the
transmitter has been disabled.
2. Typically, the antenna connected to the transmitter is fixed-mounted
on the side or top of a building, or on a tower. Depending upon the
application and the gain of the antenna, the total composite power
could exceed 200 watts EIRP. The antenna location should be such
that only qualified technical personnel can access it, and that under
normal operating conditions no other person can touch the antenna
or approach within 3.05 meters (10 feet) of the antenna.
ISO 9001 Registration
Microwave Data Systems adheres to this internationally-accepted
quality system standard.
Quality Policy Statement
We, the employees of Microwave Data Systems Inc., are committed to
understanding and exceeding our customer’s needs and expectations.
• We appreciate our customer’s patronage. They are our business.
• We promise to serve them and anticipate their needs.
RF Exposure
Separation distances
required for FCC RF
Exposure compliance
Antenna Gain vs. Recommended Safety Distance
(MDS 4790B)
Station Antenna Gain
0–5 dBi 5–10 dBi 10–16.5 dBi
Minimum RF Safety
Distance
0.79 meter 1.41 meters 3.05 meters
Antenna Gain vs. Recommended Safety Distance
(MDS 9790B)
Station Antenna Gain
0–5 dBi 5–10 dBi 10–18.65 dBi
Minimum RF Safety
Distance
0.53 meter 0.94 meter 2.58 meters

vi MDS x790B Series I/O Guide MDS 05-2765A01, Rev. B
• We are committed to providing solutions that are cost effective,
innovative and reliable, with consistently high levels of quality.
• We are committed to the continuous improvement of all of our
systems and processes, to improve product quality and increase
customer satisfaction.
Revision Notice
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 addi-
tional questions or need an exact specification for a product, please con-
tact our Customer Service Team using the information at the back of this
guide. In addition, manual updates can often be found on our Web site
at www.microwavedata.com .
FCC Part 15 Notice
The transceiver complies with Part 15 of the FCC Rules. Operation is
subject to the following 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 operation.
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 Microwave Data
Systems may void the user’s authority to operate this device. Further-
more, this device is intended to be used only when installed in accor-
dance with the instructions outlined in this manual. Failure to comply
with these instructions may also void the user’s authority to operate this
device.
Warning—400 MHz Distress Beacons
In the U.S.A., the 406 to 406.1 MHz band is reserved for use by distress
beacons. Since the MDS 4790 Series radio is capable of transmitting in
this band, take precautions to prevent the radio from transmitting
between 406 to 406.1 MHz.
ESD Notice
To prevent malfunction or damage to this radio, which may be caused
by Electrostatic Discharge (ESD), the radio should be properly
grounded by connection to the ground stud on the rear panel. In addition,
the installer or operator should follow proper ESD precautions, such as
touching a grounded bare metal object to dissipate body charge, prior to
adjusting front panel controls or connecting or disconnecting cables on
the front or rear panels.

MDS 05-2765A01, Rev. B MDS x790B Series I/O Guide vii
Environmental Information
The equipment that you purchased has required the extraction and use
of natural resources for its production. Improper disposal may contami-
nate the environment and present a health risk due to hazardous sub-
stances contained within. To avoid dissemination of these substances
into our environment, and to diminish 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 MDS or your supplier for
more information on the proper disposal of this equipment.

viii MDS x790B Series I/O Guide MDS 05-2765A01, Rev. B