Trimble 9414-450 GPS data transciever User Manual TRIMMARK III Operation Manual

Trimble Navigation Ltd GPS data transciever TRIMMARK III Operation Manual

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Operations Manual

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1. Operations Manual
2. User Manual

Operations Manual

– DRAFT –TRIMMARK IIIOperation ManualPart Number: XXXXX-00Revision: ADate: November 1999Trimble Navigation LimitedSurveying & Mapping Division645 North Mary AvenuePost Office Box 3642Sunnyvale, CA 94088-3642U.S.A.1-800-827-8000 in North America+1-408-481-8000 InternationalFax: +1-408-481-7744www.trimble.com

– DRAFT –Trimble Navigation Europe LimitedTrimble House, Meridian Office ParkOsborn Way, HookHampshire RG27 9HX ENGLAND+44-1256-760-150Fax: +44-1256-760-148Voicemail: +44-1256-761-130Trimble Navigation Singapore PTE Limited79 Anson Road# 05-02Singapore 079906SINGAPORE+65-325-5668Fax: +65-225-9989Voicemail: +65-325-5668Trimble Japan K.K.Sumitomo Hamamatsu-cho, Building 10F1-18-16 Hamamatsu-cho Minato-kuTokyo 105JAPAN+81-3-5472-0880Fax: +81-3-5472-2326Trimble Navigation New Zealand Limited11 Birmingham DriveP.O. Box 8729 RiccartonChristchurchNEW ZEALAND+64-3-339-1400Fax: +64-3-339-1417Copyright© 1999 Trimble Navigation Limited. All rights reserved. No part of this manual may be copied, photocopied, reproduced, translated, or reduced to any electronic medium or machine-readable form without prior written consent from Trimble Navigation Limited.Printed in the United States of America. Printed on recycled paper.

– DRAFT –Disclaimer of WarrantyEXCEPT AS INDICATED IN “LIMITED WARRANTY” HEREIN, TRIMBLE HARDWARE, SOFTWARE, FIRMWARE AND DOCUMENTATION IS PROVIDED “AS IS” AND WITHOUT EXPRESS OR LIMITED WARRANTY OF ANY KIND BY EITHER TRIMBLE NAVIGATION LIMITED OR ANYONE WHO HAS BEEN INVOLVED IN ITS CREATION, PRODUCTION, OR DISTRIBUTION INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK, AS TO THE QUALITY AND PERFORMANCE OF THE TRIMBLE HARDWARE, SOFTWARE, FIRMWARE AND DOCUMENTATION, IS WITH YOU. SOME STATES DO NOT ALLOW THE EXCLUSION OF IMPLIED WARRANTIES, SO THE ABOVE EXCLUSION MAY NOT APPLY TO YOU.Limitation of LiabilityIN NO EVENT WILL TRIMBLE OR ANY PERSON INVOLVED IN THE CREATION, PRODUCTION, OR DISTRIBUTION OF THE TRIMBLE PRODUCT BE LIABLE TO YOU ON ACCOUNT OF ANY CLAIM FOR ANY DAMAGES, INCLUDING ANY LOST PROFITS, LOST SAVINGS, OR OTHER SPECIAL, INCIDENTAL, CONSEQUENTIAL, OR EXEMPLARY DAMAGES, INCLUDING BUT NOT LIMITED TO ANY DAMAGES ASSESSED AGAINST OR PAID BY YOU TO ANY THIRD PARTY, RISING OUT OF THE USE, LIABILITY TO USE, QUALITY OR PERFORMANCE OF SUCH TRIMBLE PRODUCT INCLUDING HARDWARE, SOFTWARE, FIRMWARE AND DOCUMENTATION, EVEN IF TRIMBLE OR ANY SUCH PERSON OR ENTITY HAS BEEN ADVISED OF THE POSSIBILITY OF DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY. SOME STATES DO NOT ALLOW THE LIMITATION OR EXCLUSION OF LIABILITY FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATIONS MAY NOT APPLY TO YOU.Software and Firmware Limited WarrantyTrimble Navigation Limited warrants that Software and Firmware products will substantially conform to the published specifications provided it is used with the Trimble products, computer products, and operating system for which it was designed. For a period of ninety (90) days, commencing thirty (30) days after shipment from Trimble, Trimble also warrants that the magnetic media on which Software and Firmware are distributed and the documentation are free from defects in materials and workmanship. During the ninety (90) day warranty period, Trimble will replace defective media or documentation, or correct substantial program errors at no charge. If Trimble is unable to replace defective media or documentation, or correct program errors, Trimble will refund the price paid for The Software. These are your sole remedies for any breach in warranty.

– DRAFT –Hardware Limited WarrantyTrimble Navigation Limited products are warranted against defects in material and workmanship for a period of one year. The warranty period shall commence thirty (30) days after shipment from Trimble’s factory. Warranty service will be provided at a designated Trimble Service Center. Trimble will at its option either repair or replace products that prove to be defective. The Customer shall pay all shipping charges for products returned to Trimble for warranty service. Trimble shall pay all shipping charges for the return of products to the Customer. The above warranty shall not apply to defects resulting from:1. Improper or inadequate maintenance by the buyer2. Buyer-supplied software or interfacing3. Unauthorized modification or misuse4. Operation outside of the environmental specifications of the product5. Improper installation, where applicable6. Lightning or other electrical discharge7. Fresh or salt water immersion or spray8. Normal wear and tear on consumable parts (for example, batteries)No other warranty is expressed or implied. Trimble Navigation Limited specifically disclaims the implied warranties of fitness for a particular purpose and merchantability.

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TRIMMARK III Operation Manual vii– DRAFT –Table of ContentsPrefaceScope and Audience . . . . . . . . . . . . . . . . . . . . . . . . .xvOrganization . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xvRelated Information . . . . . . . . . . . . . . . . . . . . . . . . .xviUpdate Notes . . . . . . . . . . . . . . . . . . . . . . .xviOther Information . . . . . . . . . . . . . . . . . . . . . . . . . .xviWorld Wide Web (WWW) Site . . . . . . . . . . . . . .xviFile Transfer Protocol (FTP) Site . . . . . . . . . . . . .xviiTechnical Assistance . . . . . . . . . . . . . . . . . . . . . . . . .xviiReader Comment Form. . . . . . . . . . . . . . . . . . . . . . . .xviiDocument Conventions. . . . . . . . . . . . . . . . . . . . . . . .xviiiWarnings, Cautions, Notes, and Tips . . . . . . . . . . . . . . . . .xix1 Overview1.1 TRIMMARK III . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.1.1 TRIMMARK III Features . . . . . . . . . . . . . . . . .1-21.1.2 Equipment Sets and Accessories . . . . . . . . . . . . .1-3TRIMMARK III Base Equipment Set. . . . . . . . . . .1-3TRIMMARK III Repeater Equipment . . . . . . . . . .1-41.1.3 Accessories . . . . . . . . . . . . . . . . . . . . . . . .1-44000, 4400 and 4600 GPS Receiver Accessories . . . . .1-41.1.4 Typical Broadcast Network . . . . . . . . . . . . . . . .1-51.2 TRIMMARK III Description. . . . . . . . . . . . . . . . . . . . .1-6

viii TRIMMARK III Operation Manual– DRAFT –1.2.1 Controls and Indicators . . . . . . . . . . . . . . . . . .1-61.2.2 Power and I/O Cables . . . . . . . . . . . . . . . . . . .1-71.2.3 Defaults . . . . . . . . . . . . . . . . . . . . . . . . . .1-71.3 Standard Omnidirectional Antennas . . . . . . . . . . . . . . . . .1-81.4 Directional Antennas . . . . . . . . . . . . . . . . . . . . . . . . .1-82 Operation2.1 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12.1.1 Configuring the Radio Modem . . . . . . . . . . . . . .2-2Connecting to a Computer. . . . . . . . . . . . . . . . .2-22.1.2 Getting Started with CommSet . . . . . . . . . . . . . .2-3Using CommSet . . . . . . . . . . . . . . . . . . . . . .2-32.1.3 Frequency Updates . . . . . . . . . . . . . . . . . . . .2-32.2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-42.2.1 TRIMMARK III . . . . . . . . . . . . . . . . . . . . . .2-4Installation as a Base . . . . . . . . . . . . . . . . . . .2-5Installation as a Repeater . . . . . . . . . . . . . . . . .2-62.2.2 Antenna Installation . . . . . . . . . . . . . . . . . . . .2-8Line of Sight Obstruction . . . . . . . . . . . . . . . . .2-9Cable Losses. . . . . . . . . . . . . . . . . . . . . . . .2-9Antennas. . . . . . . . . . . . . . . . . . . . . . . . . .2-102.3 Verifying Operation. . . . . . . . . . . . . . . . . . . . . . . . . .2-122.3.1 TRIMMARK III . . . . . . . . . . . . . . . . . . . . . .2-12Base Operation . . . . . . . . . . . . . . . . . . . . . .2-12Repeater Operation . . . . . . . . . . . . . . . . . . . .2-123 Characteristics and Specifications3.1 Antenna Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13.1.1 Omnidirectional Antennas. . . . . . . . . . . . . . . . .3-13.2 Broadcast Network . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

TRIMMARK III Operation Manual ix – DRAFT –3.2.1 Frequency Band and Channel Selection. . . . . . . . . .3-33.2.2 Wireless Data Rate. . . . . . . . . . . . . . . . . . . . .3-43.2.3 Transmit Power . . . . . . . . . . . . . . . . . . . . . .3-43.2.4 TRIMMARK III Electrical Interface . . . . . . . . . . .3-53.3 General Specifications . . . . . . . . . . . . . . . . . . . . . . . .3-63.4 General Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-73.5 Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-74 Regulations and Safety4.1 Type Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-24.2 Licensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-24.3 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3A Using Radio Communication Systems with GPS Surveying ReceiversA.1 Selecting Communications Radios . . . . . . . . . . . . . . . . . .A-2A.2 Useful Field Procedures . . . . . . . . . . . . . . . . . . . . . . .A-5A.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-6Index

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TRIMMARK III Operation Manual xi– DRAFT –List of FiguresFigure 2-1 Standard UHF Omnidirectional Antennas . . . . . . . . . 2-11Figure 3-1 Omnidirectional Antenna Gain Patterns. . . . . . . . . . 3-2

xii TRIMMARK III Operation Manual– DRAFT –

TRIMMARK III Operation Manual xiii– DRAFT –List of TablesTable 2-1 Repeater Use in Networks . . . . . . . . . . . . . . . 2-7Table 2-2 Cable Losses . . . . . . . . . . . . . . . . . . . . 2-9Table 3-1 TRIMMARK III Physical Specifications . . . . . . . . . 3-6Table 3-2 Antenna Physical Specifications . . . . . . . . . . . . 3-6Table 3-3 Performance Specifications (Typical) . . . . . . . . . . 3-7Table A-1 RF Bands to Avoid When Using GPS Surveying Receivers . . A-3

xiv TRIMMARK III Operation Manual– DRAFT –

TRIMMARK III Operation Manual xv– DRAFT –PrefaceWelcome to the TRIMMARK™ III Operation Manual. This manual describes the TRIMMARK III radio modem for use in real-time differential and real-time kinematic GPS applications. The TRIMMARK III, when used with a Trimble 4700 or 4800 rover with an internal radio modem, provides a high-speed wireless data link between base and rover GPS receivers.Scope and AudienceWe recommend that you spend some time reading this manual. The following section provides you with a guide to this manual, as well as to other documentation you have received with this product.OrganizationThis manual contains the following chapters and appendices:•Chapter 1, Overview - provides a brief overview and physical description of the TRIMMARK III radio modem.•Chapter 2, Operation - contains complete installation and configuration instructions for the TRIMMARK III radio modem.•Chapter 3, Characteristics and Specifications - summarizes performance characteristics and specifications that can be expected from a TRIMMARK III radio modem.

xvi TRIMMARK III Operation ManualPreface– DRAFT –•Chapter 4, Regulations and Safety - contains regulation and safety information.•Appendix A, Using Radio Communications Systems with GPS Surveying Receivers - discusses the special problems encountered when using radio communication systems with GPS receivers.Related InformationThis manual contains system-wide, general information on the TRIMMARK III radio modem. Other sources of information are discussed in the following sections.Update NotesYou will find a Warranty Activation Sheet with your TRIMMARK III radio modem. By sending in your Warranty Activation Sheet, you are automatically sent update notes as they become available. When you receive these packages, read them. They contain important information about software and hardware changes. Contact your local Trimble Dealer for more information about support agreement contracts for software and firmware, and extended warranty programs for hardware.Other InformationThis section lists sources that provide other useful information.World Wide Web (WWW) SiteFor more information about Trimble, visit our site on the World Wide Web: •www.trimble.com

TRIMMARK III Operation Manual xvii Preface– DRAFT –File Transfer Protocol (FTP) SiteUse the Trimble FTP site to send files or to receive files such as software patches, utilities, and answers to Frequently Asked Questions (FAQs):• ftp://ftp.trimble.comYou can also access the FTP site from the Trimble World Wide Web site at: •www.trimble.com/support/support.htmTechnical AssistanceIf you have a problem and cannot find the information you need in the product documentation, contact your local dealer. Alternatively, request technical support using the Trimble World Wide Web site (http://www.trimble.com/support/support.htm).Reader Comment FormThank you for purchasing this product. We would appreciate feedback about the documentation. Use the reader comment form at the back of this manual or, if this is not available, send comments and suggestions to the address in the front. All comments and suggestions become the property of Trimble Navigation Limited.

xviii TRIMMARK III Operation ManualPreface– DRAFT –Document ConventionsItalics identify software menus, menu commands, dialog boxes, and the dialog box fields.SMALL CAPITALS identify DOS commands, directories, filenames, and filename extensions.Courier represents messages printed on the screen. Courier Bold represents information that you must type in a software screen or window.Helvetica Bold identifies a software command button.[Ctrl] is an example of a hardware function key that you must press on a personal computer (PC). If you must press more than one of these at the same time, this is represented by a plus sign, for example, [Ctrl] + [C].

TRIMMARK III Operation Manual xix Preface– DRAFT –Warnings, Cautions, Notes, and TipsWarnings, cautions, notes, and tips draw attention to important information and indicate its nature and purpose.MWarning – Warnings alert you to situations that could cause personal injury or unrecoverable data loss.ICaution – Cautions alert you to situations that could cause hardware damage or software error. *Note – Notes give additional significant information about the subject to increase your knowledge, or guide your actions. PTip – Tips indicate a shortcut or other time- or labor-saving hint that can help you make better use of the product.

xx TRIMMARK III Operation ManualPreface– DRAFT –

TRIMMARK III Operation Manual 1-1– DRAFT –1 OverviewThe rugged TRIMMARK III radio modem is designed for harsh environments, such as those associated with seismic and mining surveys. Used with a Trimble 4700 or 4800 rover GPS receiver with an internal radio modem, the TRIMMARK III provides a convenient, versatile means of establishing a robust wireless data broadcast network for real-time differential and real-time kinematic GPS applications.1.1 TRIMMARK IIIThe TRIMMARK III unit can be used as a base or a repeater. The function of a particular unit—base or repeater—is determined by its configuration. Units used as a base can be connected to most Trimble survey-grade GPS receivers through a single cable for serial I/O and a separate cable for power. When used as a repeater the TRIMMARK III unit operates autonomously and does not require anything connected to the serial port.To achieve line-of-sight (LOS) coverage to all points in a survey area, a TRIMMARK III radio modem network can include up to two repeaters. The repeaters retransmit data packets according to a simple time-sharing scheme to avoid mutual interference. The operation of the repeater is transparent to the rovers. The rovers can be moved while continually receiving data packets from the base or any one of the repeaters, whichever the rover detects first.

1-2 TRIMMARK III Operation ManualOverview 1– DRAFT –1.1.1 TRIMMARK III FeaturesThe TRIMMARK III has the following standard features:•Selectable, 20 channel capability through an external channel selector•Built-in channel monitor capability•Station ID selectable through the CommSet utility.•Selectable 2W/25W transmit power•Narrowband UHF technology•Up to 15 km line-of-sight range under optimal conditions•Selectable wireless data rate of 4800, 9600, or 19200 bps•Interfaces with all Trimble survey-grade GPS receivers•Operating mode selectable through the CommSet utility •Supports up to two repeaters in a single network•Rugged, weatherproof construction•Two line, 16-character VFD display•Trimble CMR and RTCM SC-104 Version 2.1 compatible*Note – As used in this manual, CMR as well as CMR Plus formats are both represented by CMR.•Carrier detect mode selectable through the CommSet Windows™ utility program

TRIMMARK III Operation Manual 1-3 1Overview– DRAFT –1.1.2 Equipment Sets and AccessoriesThe TRIMMARK III is available as a stand-alone product or in one of two convenient, standard equipment sets—the base or repeater set. These standard equipment sets are designed for use with GPS receivers such as the Trimble 4700 and 4800. The equipment sets contain many of the accessories required to operate the radio modems including cables, mounts, and antennas.TRIMMARK III Base Equipment SetThe standard TRIMMARK III Base Equipment Set consists of these components:•TRIMMARK III radio modem (410–420 MHz, 430–450 MHz, or 450–470 MHz)•Standard antenna (0 dB, 5 dB UHF)•15-foot antenna cable with integrated antenna mount•2-foot antenna mounting poles, 3 each•Tripod mounting plate•Configuration cable (PC to radio modem)•50-foot data cable (0 shell to 0 shell)•6-foot power cable•CommSet communication setup software diskette•Operation manual*Note – The standard base equipment set is designed for use with GPS receivers such as the Trimble 4700 and 4800. Contact Trimble for information about connecting other GPS receivers.

1-4 TRIMMARK III Operation ManualOverview 1– DRAFT –TRIMMARK III Repeater EquipmentThe standard TRIMMARK III Repeater Equipment Set consists of these components:•TRIMMARK III Radio Modem (410–420 MHz, 430–450 MHz, or 450–470 MHz)•Standard antenna (0 dB, 5 dB UHF)•15-foot antenna cable with integrated antenna mount•2-foot antenna mounting poles, 3 each•Tripod mounting plate•Configuration cable (PC to radio modem)•6-foot power cable•CommSet communication setup software Diskette•Operation manual1.1.3 AccessoriesThe standard equipment sets for the TRIMMARK III are designed for use with GPS receivers such as Trimble 4700 and 4800. Additional accessories must be purchased to use the TRIMMARK III with GPS receivers such as Trimble series 4000, Site Surveyor 4400, and 4600LS.4000, 4400 and 4600 GPS Receiver AccessoriesThe data cable provided as part of the standard Base equipment sets is designed for use with Trimble 4700 and 4800 GPS receivers. The following additional cable must be purchased for the use of GPS receivers such as Trimble Series 4000, Site Surveyor 4400, and the 4600LS with the TRIMMARK III radio modem.•50-foot data cable (0-shell to 1-shell) for base use

TRIMMARK III Operation Manual 1-5 1Overview– DRAFT –*Note – The 0-shell to 1-shell data cable will not connect directly to the Trimble 4600LS GPS receiver. Use this data cable along with the appropriate cable supplied with the 4600 to connect the TRIMMARK III to the 4600LS.1.1.4 Typical Broadcast NetworkThe TRIMMARK III radio modem is primarily designed to broadcast and repeat RTK (Real-Time Kinematic) data for use in GPS surveying. It is compatible with Trimble’s CMR RTK data format as well as the RTCM SC-104 Ver. 2.1 RTK data format. It is also compatible with RTCM SC-104 Ver. 1.0, Ver. 2.0 and Ver. 2.1 for DGPS broadcasts.At UHF frequencies, wireless data links are line-of-sight (LOS). LOS links are attenuated by terrain features such as buildings and trees. As a result, it is easier to bring survey control into the local work area than to stretch the wireless data link to the limit of its usability.With a LOS wireless data link, antenna height at the radio modem becomes critical. Doubling the antenna height increases radio range approximately 40%. In comparison, doubling broadcast power only provides a 10% increase in LOS range.The TRIMMARK III radio modems operate in one these frequency bands:•410–420 MHz•430–450 MHz•450–470 MHzEach unit operates in one of these bands, not across bands.

1-6 TRIMMARK III Operation ManualOverview 1– DRAFT –1.2 TRIMMARK III DescriptionThe TRIMMARK III radio modem is packaged in a weatherproof housing. The front panel has a VFD display to indicate channel frequency, status, and errors. There are four buttons on the front panel:•SPEAKER•UP•DOWN•NEXTThe rear panel has three electrical connectors:•POWER connector (two-pin LEMO)•DATA connector (seven-pin female LEMO)•ANTENNA connector (female TNC)1.2.1 Controls and IndicatorsThe NEXT button is used to browse through the various menu screens. The UP and DOWN buttons are used to change the displayed parameters in the menu screens. The selected parameters appear on the display. For example, while in the Main screen which displays channel number and frequency, the UP and DOWN buttons control channel/frequency selection. When the UP or DOWN button is pressed, the selected channel/frequency will change. The radio display shows the selected channel and frequency. Channels can only be changed when the radio is not transmitting.The SPEAKER button in the upper-left corner of the radio panel controls the volume of the received audio signal from the currently selected channel. If traffic is present, you will hear the traffic if the volume is turned on.

TRIMMARK III Operation Manual 1-7 1Overview– DRAFT –1.2.2 Power and I/O CablesThe TRIMMARK III equipment set comes with a data cable (not provided in the repeater equipment set), an antenna cable with integrated antenna mount, and a power cable. In addition a configuration cable (PC to radio modem) is provided. The configuration cable allows you to modify the radio modem configuration using the Windows-based CommSet utility, including the channel frequency, serial port settings, over-the-air baud rate, carrier detect ON/OFF setting, station ID, and the operating mode.When configured as a base, the radio modem receives data at the DATA connector through a single LEMO-to-LEMO cable that plugs into a Trimble 4700 or 4800 GPS receiver. When the unit is configured as a repeater, no data connection is required.Power is connected to the unit at the POWER connector from a suitable power source. 1.2.3 DefaultsThe TRIMMARK III radio modem is shipped from the factory with the serial I/O port configured for 38400 bps, 8 data bits, odd parity and 1 stop bit. The wireless data link is configured to communicate at 9600 bps and Carrier Detect is ON. If the base equipment set is ordered, the unit is preconfigured for Base without a Repeater operating mode, and transmit power is set to 25W. If the repeater equipment set is ordered, the unit is preconfigured for Repeater 1 operating mode, and transmit power is set to 2W.

1-8 TRIMMARK III Operation ManualOverview 1– DRAFT –1.3 Standard Omnidirectional AntennasEach radio modem, when purchased as part of a base or repeater equipment set, is supplied with a standard omnidirectional antenna. The omnidirectional antenna is a 5 dB gain UHF antenna with an interchangeable 0 dB tip. Either of these antennas can be used with a unit configured as a base or repeater. The antenna threads onto an integrated antenna mount and cable. The integrated antenna mount attaches to the antenna mounting poles on the top of a tripod using a tripod mounting plate.1.4 Directional AntennasTwo directional antenna options are available. The directional antennas should be bolted to an extended mast for maximum range at the base or repeater. Each antenna comes with an integral antenna cable for the radio modem. The integral antenna cable is not long enough to connect directly to the TRIMMARK III. An additional coaxial cable is required for most installations. The integral cable terminates in a male TNC connector.*Note – Always use the shortest, highest-quality coax cable possible between the radio modem and the antenna. Cable attenuation at the unit’s operating frequency can severely limit the radio's operational range.Additional antenna options are possible for special applications. The major trade-offs are size, weight, cost, gain, and country-of-use regulations. Characteristics and Specifications, page 3-1, describes the trade-offs involved in selecting antenna types.

TRIMMARK III Operation Manual 2-1– DRAFT –2 OperationThe TRIMMARK III radio modem contains both a data modem and a radio. It can be used in a variety of configurations with appropriate rover radio modems to form a complete wireless data network. One configuration is as a TRIMMARK III base radio modem broadcasting directly to a Trimble 4700 or 4800 rover GPS receiver equipped with an internal radio modem. TRIMMARK III units may also operate as repeaters in this network.Each TRIMMARK III radio modem can be used as soon as it is hooked up. At power-up, the configuration parameters stored in non-volatile memory initialize the unit for operation. Some of these parameters must be set to match the same values used in all units operating on a network.2.1 ConfigurationEach TRIMMARK III radio modem comes from the factory with its serial I/O port configured for 38,400 bps, 8 data bits, odd parity and 1 stop bit. The wireless data link is set to 9600 bps and carrier detect is set to ON at the factory. In addition, the TRIMMARK III is preconfigured for either the Base without a Repeater or Repeater 1 operating mode, dependent on which equipment set is ordered.

2-2 TRIMMARK III Operation ManualOperation 2– DRAFT –The factory default parameters are stored in nonvolatile memory and serve as the initial power-up settings for the radio modems. The units retrieve the parameters stored in non-volatile memory at each power-up. The power-up settings can be changed as often as necessary using the CommSet utility (COMMSET.EXE) provided on the CommSet diskette.2.1.1 Configuring the Radio ModemUsing the CommSet utility, you can set up the serial I/O parameters, operating mode, select the appropriate channel frequency, enable carrier detect, and select the Station ID. Some of these parameters also can be changed from the unit’s front panel.*Note – The BAUD RATE, FORMAT, and CTS parameters for the GPS receiver must be configured to properly transfer data between the receiver and the radio modem. BAUD RATE must be set to match the maximum serial I/O rate of the radio modem (38400 bps) and FORMAT is always set to 8-ODD-1. CTS flow control is disabled. The radio modem must be connected to a computer running Microsoft Windows 95/98 or Windows NT to run the CommSet utility (COMMSET.EXE) and its associated help file (COMMSET.HLP). Perform the following procedures to connect the unit to your computer, install the CommSet utility under Windows, and set up the desired radio modem parameters.*Note – Your computer must be able to support a 38400 bps serial port data rate.Connecting to a ComputerConnect the radio modem’s DATA connector to a COM port on the computer with the Configuration cable (DB9-LEMO). Connect power between the POWER connector on the unit and a suitable power source.

TRIMMARK III Operation Manual 2-3 2Operation– DRAFT –2.1.2 Getting Started with CommSetCommSet is a communications setup utility used for configuring TRIMMARK III parameters. You need Microsoft Windows 95, Windows 98, or Windows NT to run CommSet on your computer. Read the README.TXT file provided on the CommSet diskette or read the Microsoft Windows documentation for installation instructions. The setup program adds a CommSet command to your Windows Start menu and places and CommSet icon on the desktop. Using CommSetTo use CommSet, follow the instructions on the screen to setup the TRIMMARK III unit. For more information, refer to Commset online help.2.1.3 Frequency UpdatesEach TRIMMARK III radio modem contains a list of up to 20 preprogrammed frequencies stored in non-volatile memory. This list is preconfigured based on the frequencies requested when the unit was ordered.Governmental regulations prevent you from programming new frequencies. Only manufacturers or authorized dealers can update this frequency list. All frequencies programmed into a TRIMMARK III radio modem must comply with the host country regulations.When you want to change the frequency list (add, delete, or replace frequencies), the internal frequency list must be updated. To facilitate field updates, contact your Trimble dealer and provide the TRIMMARK III radio modem’s serial number and a complete, updated frequency list in order to obtain this update. There is a nominal charge for this service.

2-4 TRIMMARK III Operation ManualOperation 2– DRAFT –2.2 InstallationBefore setting up the equipment in the field, verify that each radio modem is set to the same frequency and wireless data rate. Also use the Commset utility to verify that the radio modem’s GPS Port (serial port) settings are 38400 Baud Rate and Odd Parity. Set the serial port settings for both the base and rover GPS receivers to 38400 bps, 8 bits, odd parity and 1 stop bit. Refer to the GPS receiver manual for general GPS receiver setup information. If these settings are not available, use the CommSet utility to set the radio modem’s serial port settings to those of the GPS receiver.*Note – High-power signals from a near-by high-power radio station or radar transmitter can overwhelm the radio modem circuits. This does not harm the instruments, but can prevent them from functioning correctly. To avoid problems, try not to use the radio modems within 400 meters of powerful radar, television, or other transmitters. Low-power transmitters such as the ones in portable phones and walkie-talkies normally do not interfere with TRIMMARK III radio modem operations unless they are tuned to the same channel as your radio modem units. Always monitor any frequency before and during operation. Only transmit on a clear channel. Also, to avoid possible interference with GPS reception, keep the base radio modem antenna as far as possible from the GPS antenna. A minimum of 10 feet is recommended.Refer to Using Radio Communication Systems with GPS Surveying Receivers, page A-1, which is a copy of Trimble publication 1-612-0082-2/94 Using Radio Communication systems with GPS Surveying Receivers, for precautions in using certain frequencies that can interfere with GPS operation.2.2.1 TRIMMARK IIIThe TRIMMARK III radio modem can be installed in a network as the base station or as a repeater.

TRIMMARK III Operation Manual 2-5 2Operation– DRAFT –Installation as a BaseTo use a TRIMMARK III radio modem as a base, do the following:1. If necessary, reconfigure the unit’s serial port settings to those of the GPS receiver using either the unit’s front panel or the CommSet utility. Depending on whether or not repeaters are to be used in the radio modem network, select the appropriate operating mode on the unit. This step is very important to ensure proper operation of the radio modem network.2. Before connecting the power cable, thread the base antenna onto its mount. Assemble the 3 antenna mounting poles together and attach the antenna mount and antenna. The 5 dB antenna tips are recommended for most applications.3. Mount the entire antenna assembly on a tripod using the tripod mounting plate and connect the antenna cable to the TRIMMARK III radio modem.4. Attach the antenna cable to the ANTENNA port on the unit.5. Connect the power cable between the TRIMMARK III unit’s POWER port and an appropriate 12V DC power source. ICaution – Be careful to connect the power cable with the correct polarity. Reversing polarity does not damage the base radio modem, but the protective 10 Amp fuse in the power cable will blow.6. The front panel display should display the channel frequency and status. Listen to the channel you are planning to operate on using the built-in speaker or an external scanner. Change the channel if you hear other users.7. Connect the 50-foot data cable between the base radio modem DATA port and the GPS receiver data port. For the Trimble 4700 and 4800 GPS receivers, this is Port 3 (the 7-pin connector).

2-6 TRIMMARK III Operation ManualOperation 2– DRAFT –If the GPS receiver is outputting data, the base should now be in operation. Check the display on the front panel of the base unit to verify operation when transmitting. A blinking TX indicates normal transmission is in progress.The TRIMMARK III radio modem at the base location broadcasts all data it receives from the base GPS receiver to the rovers and repeaters in the network.*Note – To avoid possible interference with GPS reception, keep the radio modem antenna as far as possible from any GPS antenna. A minimum of 10 feet is recommended.Installation as a RepeaterTo achieve coverage to all points in a survey area, a TRIMMARK III network may include up to two repeaters under certain conditions. The repeaters retransmit data packets in a way that avoids mutual interference with the base. The operation of the repeaters is transparent to the rovers. A rover can be moved and collect data packets from the base or repeaters, whichever the rover receives first.The option to include repeaters in a TRIMMARK III network depends on the selected wireless data rate and the broadcast information content and rate (that is, CMR vs. RTCM 2.1 RTK packets at 1Hz vs. 2Hz RTK epoch rates). Table 2-1 illustrates when and how many repeaters may be used in a network for various wireless data rates, RTK formats and RTK epoch rates.

TRIMMARK III Operation Manual 2-7 2Operation– DRAFT –To install a TRIMMARK III radio modem as a repeater, do the following:1. Verify that the TRIMMARK III is configured to operate in Repeater 1 or Repeater 2 radio mode using the front panel or CommSet utility, see page 2-3.2. Also using CommSet, verify that the Base is set to be used as Base with Repeater 1 or as a Base with 2 Repeaters. It is very important to change the Operating Mode of the Base as well as the repeaters; otherwise, the radio modem network will not operate properly.3. Before connecting the power cable, thread the repeater antenna onto its mount. Assemble the 3 antenna mounting poles together and attach the antenna mount and antenna. The 5 dB antenna tips are recommended for most applications.4. Mount the entire antenna assembly on a tripod using the tripod mounting plate, and connect the antenna cable to the TRIMMARK III radio modem.5. Attach the antenna cable to the ANTENNA port on the unit.Table 2-1 Repeater Use in NetworksWireless Data Rate (bps) RTCM 2.0 DGPS @ 1Hz CMR @ 1 Hz CMR @ 5 HzRTCM 2.1 DGPS & RTK @ 1 Hz4800 1 1 X X9600 2 2 0 019200 2 2 1 1X Wireless data link is inoperable.0 No repeaters may be used.1 One repeater possible.2 Two repeaters possible.

2-8 TRIMMARK III Operation ManualOperation 2– DRAFT –6. Connect the power cable between the TRIMMARK III unit’s POWER port and an appropriate 12V DC power source. The front panel should display the channel frequency as well as status.ICaution – Be careful to connect the power cable with the correct polarity. Reversing polarity does not damage the base radio modem, but the protective 10 Amp fuse in the power cable will blow.7. Set the repeater’s channel frequency to match the base radio modem’s channel frequency. Radio modem channels are changed by using the UP and DOWN arrow keys from the Main screen. Channels can be changed only when the radio is not transmitting. The channel number/frequency in use is displayed on the front panel. 8. Verify that the channel assignments are the same for all base, repeater, and rover units. The repeater should now be in operation. The display on the front panel will blink "RPT", indicating proper operation of the repeater.2.2.2 Antenna InstallationSeveral factors should be considered when installing and locating antennas. Place antennas as high as possible above the ground and surrounding obstructions such as trees, vehicles, buildings, and hills.*Note – Antenna height is the most important factor in achieving maximum range with radio modems. Doubling the antenna height results in a 40% increase in line-of-sight range.

TRIMMARK III Operation Manual 2-9 2Operation– DRAFT –Line of Sight ObstructionObjects placed near the antennas, especially metal objects, can severely limit their efficiency. If an antenna is to be mounted on an antenna mast, make sure the antenna is mounted so that its radiating element is completely above the top of any obstructing source if possible.PTip – Keep the radio modem unit near its antenna. Mount the unit as close as possible to the antenna, rather than running a long length of cable from the unit to an antenna, see Table 2-2.Cable LossesThe cable length between the TRIMMARK III radio modem and its antenna affects antenna range. Cable introduces loss in overall power transmitted by your TRIMMARK III radio modem. Table 2-2 lists typical loss characteristics for three popular types of coaxial cable. The losses are expressed in dB/100 feet of cable. Remember that connectors add an additional 0.25 to 0.5 dB loss per connector.*Note – Typically 3 dB signal loss = 50% power loss = 30% range reduction.Table 2-2 Cable LossesCable Type Cable Loss at 150 MHz (dB/100 Feet) Cable Loss at 450 MHz (dB/100 Feet)RG-58 6 dB 12 dBRG-214 3 dB 5 dB5/8" Heliax®0.5 dB 1 dB

2-10 TRIMMARK III Operation ManualOperation 2– DRAFT –AntennasThree different omnidirectional UHF antennas, see Figure 2-4, are available with both a 0dB tip and a 5dB tip. One antenna is used with 410–420 MHz radio modems, one is used with 430–450 MHz radio modems, and a separate antenna is used with 450–470 MHz radio modems.The base of all standard antennas have a spring tab that must make good contact with the button in the center top of the antenna mount. If range seems limited to a few hundred feet, verify that this tab is properly aligned.

TRIMMARK III Operation Manual 2-11 2Operation– DRAFT –Figure 2-1 Standard UHF Omnidirectional Antennas5 dB gain tipL2Hand tighten desired antennatip onto antenna feed.Check that the contact tab inthe base of the antenna feedis at a 45 ˚ angle.(0.2 to 0.25 in.)0 dB gain tipL1 0.5 to 0.6 cmIMPORTANTCheck these lengths and adjust if necessary by loosening Allen screwFrequency Band (MHZ)L1 (cm) (in) (cm) (in)410-420 20.3 8 15.0 5.9430-450 17.4 6.8 12.3 4.8450-470 16.9 6.6 13.3 5.2IMPORTANTL2

2-12 TRIMMARK III Operation ManualOperation 2– DRAFT –2.3 Verifying OperationTest the TRIMMARK III radio modem for proper operation. Always monitor any frequency before and during operation. Only transmit on a clear channel. Turn Carrier Detect ON to automatically monitor a channel. If Carrier Detect is ON, the unit will only transmit when it cannot hear anyone else on the channel. U.S. users should also enable Station ID and enter the appropriate call sign to comply with FCC regulations.2.3.1 TRIMMARK IIIThe following sections describe how to verify the operation of the TRIMMARK III radio modem.Base OperationVerify the operation of the TRIMMARK III radio modem by watching the TX icon in the display on the front panel. In units configured for base use, the TX icon blinks to indicate successful data transmission.Radio modem channels are changed by pressing the UP or DOWN buttons on the radio from the Main screen. Channels can be changed only when the radio is not transmitting. The channel number/frequency in use is displayed on the radio display. To avoid possible interference with GPS reception, keep the radio modem antenna as far as possible from the GPS antenna. A minimum of 10 feet is recommended.Repeater OperationDepending on the configuration, the repeater can receive data broadcast by either the base or another repeater. When such data is received and successfully transmitted by the repeater, RPT will blink on the front panel display.

TRIMMARK III Operation Manual 3-1– DRAFT –3 Characteristics and SpecificationsThis chapter briefly summarizes performance characteristics and specifications that can be expected from a TRIMMARK III radio modem.3.1 Antenna GainThe antennas supplied with the TRIMMARK III do not increase the energy radiated by the radio modem. They concentrate the energy from the radio modem in a particular direction. The degree to which they concentrate radio frequency energy in any particular direction is called directivity and is measured in dB, or decibels. The greater the antenna gain in dB, the higher the directivity and the more the radiated energy from the antenna is concentrated in some direction.3.1.1 Omnidirectional AntennasAn antenna that radiates energy equally in all directions in the horizontal plane is called omnidirectional. Omnidirectional antennas radiate an equal amount of energy at every azimuth. However, they are not omnidirectional in the vertical plane.

3-2 TRIMMARK III Operation ManualCharacteristics and Specifications 3– DRAFT –Figure 3-1 shows the radiated energy patterns of the omnidirectional antennas used with the radio modems. All omnidirectional antennas must be oriented vertically when used.Figure 3-1 Omnidirectional Antenna Gain PatternsThe top view shows radiated energy patterns in the horizontal, or azimuth plane of the antennas, the plane that perpendicularly bisects the length of the antenna. For omnidirectional antennas, all azimuths receive equal energy, but the 5 dB antenna radiates almost four times more power in the horizontal plane than does the 0 dB antenna. In an open field, four times more power approximately doubles the range.AzimuthElevation0 dB5 dB12˚45˚ground levelviewtop view

TRIMMARK III Operation Manual 3-3 3Characteristics and Specifications– DRAFT –The bottom view shows radiated energy patterns in the vertical, or elevation, plane of the antennas. Much of the energy from the 5 dB antenna is concentrated in elevation to within ±12° of horizontal. A rover antenna within this sector receives stronger signals from a 5 dB antenna. However, at angles greater than 12° from horizontal, the 0 dB gain antenna radiates more energy.Antenna gain has exactly the same effect on signal reception as it does on signal transmission. A high gain rover antenna can increase range performance as long as it is oriented correctly with respect to the transmit antenna. For high gain antennas, this means keeping the antenna element vertical and at the same elevation as the transmitting antenna. Otherwise, it may be better to use an antenna with less gain.3.2 Broadcast NetworkThe following sections describe the frequency bands, channel spacings and wireless data rates available with the TRIMMARK III radio modem.3.2.1 Frequency Band and Channel SelectionThe TRIMMARK III radio modem operates in one the following frequency bands:•410 to 420 MHz•430 to 450 MHz•450 to 470 MHzEach unit operates in one of these bands, not across bands. The TRIMMARK III radio modem stores up to 20 factory pre-programmed frequencies, and operates on one of these frequencies, depending on which is selected. All 20 frequencies must reside within one of the above frequency bands. These frequencies are preset at the factory.

3-4 TRIMMARK III Operation ManualCharacteristics and Specifications 3– DRAFT –*Note – Each radio modem in a network must be tuned to the same frequency in order for the network to operate.In addition, the TRIMMARK III radio modem is available in two different channel spacing configurations: 12.5 kHz and 25 kHz. Channel spacing refers to the minimum separation, in Hz, between two adjacent frequencies and can be viewed as the tuning resolution of the radio modem. Channel spacing is dependent on local government regulations.3.2.2 Wireless Data RateThe wireless data rate is the speed, in bits per second (bps), at which the base unit transmits data to the rover unit. The TRIMMARK III can be used only at 4800, 9600, or 19,200 bps.*Note – Each radio modem in a wireless data network must have the same wireless data rate and channel spacing.3.2.3 Transmit PowerThe TRIMMARK III can be used as a base transmitter or as a repeater.Each unit can be configured to transmit 2W or 25W of power. The transmit power can be configured from the front panel of the unit or by using the CommSet utility. Units shipped as part of the base equipment set are set to 25W at the factory. Units shipped as part of the repeater set are set to 2W at the factory.

TRIMMARK III Operation Manual 3-5 3Characteristics and Specifications– DRAFT –3.2.4 TRIMMARK III Electrical InterfaceThe TRIMMARK III rear panel has a grounding stud and three connectors:•POWER•DATA•ANTENNAThe POWER connector is a 2-pin LEMO connector (+VDC, GND). Be careful to connect the power cable with the correct polarity. Reversing polarity does not damage the base radio modem, but the protective 10 Amp fuse in the power cable will blow.The DATA connector is a 7-pin LEMO connector. The antenna connector on the TRIMMARK III radio modem is a female TNC. The antenna should be connected to this port with the shortest, highest-quality coax cable possible.*Note – Long antenna cables seriously degrade the range of the wireless data network.

3-6 TRIMMARK III Operation ManualCharacteristics and Specifications 3– DRAFT –3.3 General SpecificationsThe following tables contain information on the TRIMMARK III radio modems and antennas.Table 3-1 TRIMMARK III Physical SpecificationsSize 12.5 cm (4.9 in.) Wide22.9 cm (9.0 in.) Deep7.9 cm (3.1 in.) HighWeight 1.59 kg (3.5 lbs)Power Input 10 VDC to 16 VDC, nominalConnectors Power 2-pin LEMO (+VDC, GND)Data 7-pin female LEMO (supports RXD, TXD and SGND)Antenna TNC femaleTemperature Operating –40 ° to +65 ° C (–40 ° to +149 ° F)Storage –55 ° to +75 ° C (–67 ° to +167 ° F)Humidity 100%, fully sealed, weatherproof Table 3-2 Antenna Physical SpecificationsType Length (typical) WeightStandard 0 dB UHF omni whip 47 cm (18.5 in.) 0.5 kg (1.0 lb.)Standard 5 dB UHF omni whip 99 cm (39 in.) 0.5 kg (1.1 lb.)

TRIMMARK III Operation Manual 3-7 3Characteristics and Specifications– DRAFT –3.4 General CareThe TRIMMARK III radio modem is designed to tolerate the normal rough treatment that equipment can suffer in the field. However, these units are high-precision electronic instruments, and should be treated with reasonable care. The radio modems operate in temperatures from –40° to +65° Celsius (–40°F to +149°F). The enclosures are sealed and buoyant.MWarning – Operating or storing your TRIMMARK III radio modem outside the specified temperature range can destroy or limit the longevity of the instruments.3.5 ServiceThere are no user serviceable parts with the TRIMMARK III. Contact your Trimble dealer for information about obtaining service for your product. Refer to the Preface at the front of this manual for information about getting technical assistance.Table 3-3 Performance Specifications (Typical)Transmit Power Selectable 2W / 25WWireless Data Rate 4800, 9600, or 19,200 bpsFrequency Bands 410–420 MHz, 430–450 MHz, or 450–470 MHz. Only one band per radio modemChannel Spacing 12.5 kHz or 25 kHz. Only one per radio modemNumber of Channels Up to 20 factory preprogrammed frequencies, internally stored1RF Modulation Format Gaussian Minimum Shift Keying (GMSK) Serial Port One set of RS-232 signals available. Data is 8 bits with selectable parity and 1 stop bit. Supported data rates are 9600 and 38400 bps.1. Use the same frequency for all radio modems in the same wireless data network.

3-8 TRIMMARK III Operation ManualCharacteristics and Specifications 3– DRAFT –

TRIMMARK III Operation Manual 4-1– DRAFT –4 Regulations and SafetyRegulations regarding the use of the radio modems vary greatly from country to country. In some countries, the unit can be used without obtaining an end-user license. However, most countries require end-user licensing. Consult your local communications governing agency for licensing information.Before operating a TRIMMARK III radio modem, determine if authorization or a license to operate the unit is required in your country. Obtaining an operator’s permit or license for the TRIMMARK III for the location or country-of-use is the responsibility of the end user.*Note – This device complies with Part 15 of the FCC Rules. Operation is subject to the condition that this device does not cause harmful interference.

4-2 TRIMMARK III Operation ManualRegulations and Safety 4– DRAFT –4.1 Type ApprovalType Approval, or acceptance, covers technical parameters of the equipment related to emissions that can cause interference. Type Approval is granted to the manufacturer of the transmission equipment, independent from the operation or licensing of the units. (Licensing or application for operation is the responsibility of the user.) Some countries have unique technical requirements for operation in certain radio modem frequency bands. To comply with those requirements, Trimble may have modified your equipment in order to be granted Type Approval. Unauthorized modification to the units voids the Type Approval, the warranty and the operational license of the equipment.ICaution – Changes or modifications to this equipment not approved, in writing, by Trimble Navigation Limited voids your authority to operate the equipment.4.2 LicensingMany countries require that the operator of a radio, or radio modem, obtain a license prior to operating the radio, or radio modem. Some do not. Consult your local communications governing agency for licensing information. Obtaining an operator’s permit or license for the TRIMMARK III for the location or country-of-use is the responsibility of the end user.Before operating this radio modem, you are legally required to obtain frequency licenses as required by the country-of-use. Please contact your local communications governing agency for the licensing requirements for each of these radio modems.

TRIMMARK III Operation Manual 4-3 4Regulations and Safety– DRAFT –4.3 SafetyExposure to RF energy is an important safety consideration. The FCC has adopted a safety standard for human exposure to radio frequency electromagnetic energy emitted by FCC regulated equipment as a result of its actions in General Docket 79-144 on March 13, 1986. Proper use of this radio modem results in exposure below government limits. The following precautions are recommended:•DO NOT operate the transmitter when someone is within two feet (0.6 meter) of the antenna.•DO NOT operate the transmitter unless all RF connectors are secure and any open connectors are properly terminated.•DO NOT operate the equipment near electrical blasting caps or in an explosive atmosphere.•All equipment must be properly grounded according to Trimble installation instructions for safe operation.•All equipment should be serviced only by a qualified technician.

4-4 TRIMMARK III Operation ManualRegulations and Safety 4– DRAFT –

TRIMMARK III Operation Manual A-1– DRAFT –A Using Radio Communication Systems with GPS Surveying ReceiversTrimble Publication 1-612-0082-2/94"GPS receiver, antenna, tripod, tribrach, tape, cones, flagging, radio...", such is the checklist of most GPS surveyors preparing for a day of observations. But a truly successful survey is not just a matter of making sure that you have all of the equipment, you must also ensure that you optimize the usage of these new tools for the highest productivity.The GPS receiver is trying to measure very faint radio signals from satellites orbiting at 22,000 kilometers in space. There are many factors that can hinder the receiver’s ability to perform. For example, placing your hand over the antenna or setting up the antenna under a tree are factors that have already proven to interfere with GPS signal reception.

A-2 TRIMMARK III Operation ManualUsing Radio Communication Systems with GPS Surveying Receivers A– DRAFT –As GPS receivers developed, their processors have become more sensitive to incoming data flow. This provides an increase in accuracy by extracting more information out of the GPS radio signal. But with this gain in accuracy, there is an increased susceptibility to other radio signals. The receiver is now more sensitive to the incoming GPS signal, and consequently it is also more sensitive to other incoming radio signals. This means that communications radios, such as ones commonly used by surveyors, can sometimes create difficulty with the GPS signal reception.There are some very simple steps you can follow to remove the effects of radio interference on the GPS receiver. First, you should be aware of the type of communications equipment you’re buying and understand its characteristics. Secondly, a little care in using communications radio can greatly decrease your chances of experiencing any interference with satellite tracking.A.1 Selecting Communications RadiosIf you do not already have communications radios, and are thinking of buying them to supplement your survey activities, there are a couple of factors to keep in mind before purchasing: (a) some frequencies can cause interruptions or GPS tracking; (b) certain communications equipment creates spurious signals not related to their frequency that can interfere with satellite tracking; and (c) powerful communications transmitters can create such a strong radio signal that the GPS signal cannot be identified.Most communication transmitters emit overtones of their assigned frequency. If these overtones line up with the GPS frequency, it can filter into the GPS equipment and interfere with the satellite tracking. Some communication transmitters emit more of these overtones than others. But the number of overtones can be difficult to determine and is not the most important factor when considering this nuisance parameter. To avoid being affected by transmitter overtones, simply avoid those frequencies that lie within the GPS frequency range.

TRIMMARK III Operation Manual A-3 AUsing Radio Communication Systems with GPS Surveying Receivers– DRAFT –Table A-1 shows frequency bands that you should avoid.Table A-1 RF Bands to Avoid When Using GPS Surveying ReceiversFrom this Frequency To this Frequency781.210 794.210607.300 620.300520.806 529.473404.866 413.533390.605 397.105312.484 317.684303.650 310.150260.403 264.736242.920 248.120223.202 226.917202.433 206.766195.302 198.552173.602 177.228156.242 158.842151.825 155.075142.038 144.401134.955 137.844130.201 132.368120.186 124.060110.418 113.458

A-4 TRIMMARK III Operation ManualUsing Radio Communication Systems with GPS Surveying Receivers A– DRAFT –Some communication transmitters and receivers also emit spurious signals. These are extremely difficult to predict. So, the only way to know if your receiver is being hampered by spuriously emitted signals is to test the communication equipment with the GPS receiver. If you plan to buy a new radio, the best course of action is to test it with your existing GPS equipment, to determine any problems exist.Communications equipment that uses more power is more likely to create signals from which the GPS signal cannot be extracted. This case typically occurs from signals emitted from the radio transmitter box and not its antenna. Non-GPS signals enter the GPS system through the GPS antenna and not through the receiver. Therefore, most of the effects of non-GPS signals can be minimized by physically separating your radio and GPS equipment.

TRIMMARK III Operation Manual A-5 AUsing Radio Communication Systems with GPS Surveying Receivers– DRAFT –A.2 Useful Field ProceduresThere are a few useful field procedures that you can follow to minimize the effects of your radio. Since most of the radio signal in the GPS band is emitted directly from the radio transmitter box and received via the GPS antenna, make sure the GPS antenna is separated from the radio transmitter by 2-3 meters. If you are still experiencing difficulties at this distance the GPS signal may be getting over-powered by the radio transmissions. In this case, you can either separate the equipment even more or shield the radio transmitter.Radio signal strength drops as you move further away from the source of the transmission – dropping as a square of the distance. Therefore, if there is a problem, separate the GPS antenna and radio even more to lessen the strength of the radio signal received at the GPS antenna.If you are using a geodetic antenna, you can use the antenna’s ground plane to shield the radio waves. In fact, you can shield the antenna from the radio signal by moving behind nearby objects such as a car or tree. If you cannot move away from the GPS antenna, move the radio below the level of the GPS antenna ground plane. This is not ideal, but may help in those cases where you are left with no alternative.

A-6 TRIMMARK III Operation ManualUsing Radio Communication Systems with GPS Surveying Receivers A– DRAFT –A.3 SummaryUsing communications radios with GPS receivers requires some special considerations. By striving to extract the utmost accuracy from the GPS system, receiver designs have made greater use of the radio spectrum. However, the methods used to increase performance and accuracy also make GPS receivers more susceptible to receiving other radio signals.Radio signals in the GPS band arise from a few different sources. Some radio transmitters produce overtones of their frequency, which lie within the GPS P-code frequency range. Others create random, spurious signals, which affect GPS signal reception. Still other radio systems use high power levels to boost communication range and create noise that limits the GPS signal tracking. These are all characteristics to avoid when purchasing or using communications equipment in conjunction with GPS.Before using radios on full-fledged survey job, it is a good idea to test the communications equipment to determine if it affects the GPS signal reception in any way. Testing radios with the GPS equipment is especially important if you are considering purchasing new radios. Be sure to always:•Choose the communication frequency of your radios carefully so they do not transmit on or create harmonics in the frequency range of GPS.•Prior to buying radios, make sure that you test them with your GPS receivers.•If problems arise, put some distance between the radio transmitter case and the GPS antenna. Also, shielding the radio transmitter should minimize the effects of radio signals on the GPS signal reception.Radio signal strength drops as a function of distance. The greater the separation between the GPS antenna and the radio transmitter, the less likely you are to experience the interruptions in satellite tracking.

TRIMMARK III Operation Manual Index-1– DRAFT –IndexNumerics1 stop bit 2-138,400 bps 2-18 data bits 2-1Aaccessories 1-3ANTENNAcable 2-5connector 1-6, 3-5electrical interface 3-5installation 2-5port 2-7specifications 3-6antenna 2-90 dB 3-25 dB 3-2cable attenuation 1-8cable losses 2-9directional 1-8doubling broadcast power 1-5doubling height 1-5gain 3-1omnidirectional antennas 3-1height 2-8installation 2-8obstructions 2-8omnidirectional 1-8, 3-1physical specifications 3-6attenuationantenna cable 1-8audience xvBbase equipment set 1-3operation 2-12Base without a repeateroperating mode 2-1Base without repeateroperating mode 1-7baud rateserial port 2-2broadcast networkelectrical interface 3-5frequency band and channel selection 3-3overview 3-3transmit power 3-4wireless data rate 3-4buttonDOWN 1-6

Index-2 TRIMMARK III Operation ManualIndex– DRAFT –NEXT 1-6SPEAKER 1-6UP 1-6Ccable ANTENNA 2-5DATA 2-5directional antenna 1-8I/O 1-7omnidirectional antenna 1-8POWER 2-5power 1-7power losses 2-9carrier detectdefault 1-7cautions xixchannelspacing 3-7characteristics 3-1COM port 2-2CommSet utilityconfiguringradio modem 2-2getting started 2-3help 2-2radio modem configuration 1-7, 2-2using 2-3configurationcomputer connection 2-2overview 2-1radio modem 2-2serial DATA port 2-2TRIMMARK III 2-1rover 2-1connectingPC 2-2connectorANTENNA 1-6, 3-5DATA 1-6, 3-5POWER 3-5POWER & I/O 3-5controls and indicatorsTRIMMARK III 1-6copyright iiDDATAconnector 1-6, 3-5electrical interface 3-5port 2-5specifications 3-6data modem 2-1defaultscarrier detect 1-7serial communication parameters 1-7transmit power 1-7TRIMMARK III 1-7directional antenna 1-8disclaimer of warranty ivdocument conventions xviiiEelectrical interfacebroadcast network 3-5equipment sets 1-3repeater 1-4TRIMMARK III 1-3

TRIMMARK III Operation Manual Index-3 Index– DRAFT –FFCC call sign 2-12compliance 4-1safety standard 4-3type approval 4-2field proceduresTRIMMARK III A-5File Transfer Protocol (FTP) site xviiformatserial I/O port 2-2frequenciespreprogrammed 3-7frequencybands 1-5, 3-7operating 1-8updates 2-3ftp.trimble.com xviiGgeneralcare 3-7specifications 3-6GMSKRF modulation format 3-7II/O cableTRIMMARK III 1-7installationantenna 2-8ANTENNA cable 2-5base 2-5DATA cable 2-5overview 2-4POWER cable 2-5repeater 2-6TRIMMARK III 2-4LlicensingTRIMMARK III 4-2limitation of liability ivlimited warrantyfirmware ivsoftware ivline-of-sight (LOS)achieving coverage 1-1obstructions 2-9wireless data links 1-5LOS (line-of-sight)achieving coverage 1-1wireless data links 1-5Nnetworkrepeater usage 2-7NEXT button 1-6notes xixnotices iiinumberof channels 3-7Oobstructionsline-of-sight 2-9odd parity 2-1

Index-4 TRIMMARK III Operation ManualIndex– DRAFT –omnidirectional antenna 1-8omnidirectional antennasgain 3-1gain patterns 3-2operation 2-10operating modeBase without a repeater 2-1Base without repeater 1-7Repeater 1 1-7, 2-1operationbase 2-12repeater 2-12TRIMMARK III 2-1TRIMMARK Rover 2-1organization xvoverviewTRIMMARK III 1-1Pperformancespecifications 3-7TRIMMARK III 3-7physical specificationsTRIMMARK III 3-6port ANTENNA 2-5DATA 2-5POWER 2-5POWERconnector 1-6, 3-5electrical interface 3-5port 2-5specifications 3-6preface xvRradio 2-1frequency bands to avoid when using GPS surveying receivers A-3using A-1radio modeRepeater 1 2-7Repeater 2 2-7range operational limitations 1-8reader comment form xviiregulations 4-1affecting TRIMMARK III 4-1repeater 1-1installation 2-6operation 2-12use in networks 2-7Repeater 1operating mode 1-7, 2-1radio mode 2-7Repeater 2radio mode 2-7revision notice iiiRF bands to avoid A-3energy iii, 4-3modulation format 3-7rover 1-1Ssafety 4-1overview 4-3TRIMMARK III 4-1scope xv

TRIMMARK III Operation Manual Index-5 Index– DRAFT –selectingcommunications radios A-2serial DATA portconfiguration 2-2format 2-2port 3-7baud rate 2-2serviceTRIMMARK III 3-7setup CommSet utility 2-3SPEAKER button 1-6specifications 3-1antenna 3-6ANTENNA port 3-6DATA port 3-6general 3-6performance 3-7physical 3-6POWER port 3-6TRIMMARK III 3-1Ttechnical assistance xviitemperatureoperating 3-6storage 3-6tips xixtrademarks iiitransmitpower 3-7broadcast network 3-4power default 1-7Trimblepublication 1-612-0082-2/94 A-1TRIMMARK III 1-3accessories 1-3antenna physical characteristics 3-6base equipment set 1-3operation 2-12buttons 1-6characteristics and specifications 3-1configuration 2-1connectorANTENNA 1-6DATA 1-6POWER 1-6specifications 3-6controls and indicators 1-6DATAcable 1-7connector 1-7defaults 1-7description 1-6directional antenna 1-8equipment sets 1-3repeater 1-4FCC compliance 4-1type approval 4-2features 1-2field procedures A-5frequency updates 2-3general care 3-7general specifications 3-6installation 2-4base 2-5repeater 2-6licensing 4-2

Index-6 TRIMMARK III Operation ManualIndex– DRAFT –omnidirectional antenna 1-8operating temperature 3-6operation 2-1overview 1-1physical specifications 3-6POWERcable 1-7connector 1-7power 3-6radio modemnetwork 3-1regulations and safety 4-1repeaterequipment 1-4operation 2-12usage 2-7RF bands to avoid A-3rover configuration 2-1safety 4-1, 4-3service 3-7size 3-6specificationsperformance 3-7storage temperature 3-6supported frequency bands 1-5typical broadcast network 1-5verifying operation 2-12weight 3-6type approvalFCC 4-2typical broadcast networkTRIMMARK III 1-5Uupdate notes xviusingradio communication systems with GPS surveying receivers A-1Vverifyingbase operation 2-12repeater operation 2-12Wwarnings xixwirelessdata linkdefault 1-7data links 1-5data rate 3-4, 3-7broadcast network 3-4World Wide Web (WWW) site xviwww.trimble.com xviwww.trimble.com/support/support.htm xvii

– DRAFT –Reader Comment FormTRIMMARK III Operation Manual November 1999P/N: XXXXX-00 Revision AWe appreciate your comments and suggestions for improving this publication. Contributors of particularly helpful evaluations will receive a thank-you gift.I use the following Trimble product__________________________________________________________________________________________________________________________for_________________________________________________________________________Please circle a response for each of the statements below:1 = Strongly Agree 2 = Agree 3 = Neutral 4 = Disagree 5 = Strongly DisagreeThe manual is well organized 12345I can find the information I want. 12345The information in the manual is accurate. 12345I can easily understand the instructions. 12345The manual contains enough examples. 12345The examples are appropriate and helpful. 12345The layout and format are attractive and useful. 12345The illustrations are clear and helpful. 12345The manual is: too long just right too shortPlease answer the following questions:Which sections do you use the most? _____________________________________________What do you like best about the manual? _____________________________________________________________________________________________________________________What do you like least about the manual? _____________________________________________________________________________________________________________________OptionalName ______________________________________________________________________Company ___________________________________________________________________Address________________________________________________________________________________________________________________________________________________Telephone___________________________________________________________________Fax ________________________________________________________________________Please mail to the local office listed on the back cover or, to Trimble Navigation Limited, 645 North Mary Avenue, Post Office Box 3642, Sunnyvale, CA 94088-3642. All comments and suggestions become the property of Trimble Navigation Limited.

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