Sokkia GRX3 User manual

GRX3
Operator Manual
GNSS Receiver
GRX3
Operator Manual
GNSS Receiver
GRX3
Operator Manual
GNSS Receiver

GRX3
GNSS Receiver
Operator Manual
©2022, Sokkia
Part Number 1030371-01
Revision C

P/N: 1030371-01 i
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iv
Introduction
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
GRX3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Unpacking Your Receiver Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Standard Kit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Technical Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Using Sokkia Software With Your Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Getting Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Website . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Getting Acquainted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Receiver Enclosure—Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Receiver Enclosure—Display Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Receiver Enclosure—SIM Card Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Receiver Enclosure — GRX3 Hardware Reset Button . . . . . . . . . . . . . . . . . . . . 2-4
Receiver Enclosure—Bottom Overview Labels. . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
External Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Receiver Enclosure Top—Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Receiver Enclosure Bottom—Connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Display Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Power Button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
LED Display Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Receiver Status LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Status LED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Recording LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Communication LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Bluetooth LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Cellular LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Radio LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Battery LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
Managing Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Turning the Receiver On/Off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Table of Contents

Table of Contents
ii P/N: 1030371-01
Powering the Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Operating Hours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Charging the Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Battery Charging Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Surveying While Charging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Using an External Power Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Insufficient Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Installing Sokkia Receiver Utility (SRU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Loading New Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Option Authorization Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Checking the Receiver’s OAF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Loading an OAF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Performing a Factory Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Perform a Factory Reset Using SRU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Perform a Factory Reset Using the LED Display . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
Using TILT Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
HIMU Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15
System Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Setting Up the Base Receiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Setting Up the Rover Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Using GRX3 with External Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Measuring Antenna Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Collecting Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Setting Recording Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Logging Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Recording Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Recording Data via the LED Display Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Recording Data Using Sokkia Receiver Utility (SRU). . . . . . . . . . . . . . . . . . . . . . 7-2
Managing Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
USB Connection Specifics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Downloading Data Files Using SRU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Deleting Data Files from the Receiver Memory Using SRU. . . . . . . . . . . . . . . . . 7-11
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Check This First . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Powering Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Receiver Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Table of Contents
iii
P/N: 1030371-01
Bluetooth Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
SRU Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Cleaning and Storing the Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Getting Customer Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
General Details. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
R2 Lite UHF Internal Modem Board Details (Optional) . . . . . . . . . . . . . . . . . . . . 9-7
General Recommendation for Highly Reliable Radio Links. . . . . . . . . . . . . . . . . 9-7
Bluetooth Module Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Connector Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Radio (Modem) RF Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
Cellular Module RF Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
Power Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
Serial RS-232 Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
Micro-USB Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-11
Product Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10-1
Safety Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-1
General Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
Battery Pack Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
Receiver Warnings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Usage Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Regulatory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-1
FCC Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-1
ISED Canada Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-1
Community of Europe Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-2
European Community Declaration of Conformity . . . . . . . . . . . . . . . . . . . . . . . . 12-2
Restrictions on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-2
Product Conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-2
Declaration of Conformity
(Radio Equipment Directive 2014/53/EU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-3
WEEE Directive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-4
Japan Bluetooth SiteComm Module Compliance . . . . . . . . . . . . . . . . . . . . . . . . 12-4
Bluetooth Transmission Statements/Compliance . . . . . . . . . . . . . . . . . . . . . . . . 12-5
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13-1

P/N: 1030371-01 iv
Preface
Thank you for purchasing this Sokkia product. The materials available in this Manual (the “Manual”)
have been prepared by Topcon Positioning Systems, Inc. (“TPS”) for owners of Sokkia products and
are designed to assist owners with the use of the receiver and its use is subject to these terms and
conditions (the “Terms and Conditions”).
Terms and Conditions
Use
This product is designed to be used by a professional. The user should have a good knowledge of the
safe use of the product and implement the types of safety procedures recommended by the local
government protection agency for both private use and commercial job sites.
Copyrights
All information contained in this Manual is the intellectual property of and copyrighted material of TPS.
All rights are reserved. Do not use, access, copy, store, display, create derivative works of, sell, modify,
publish, distribute or allow any third party access to, any graphics, content, information or data in this
Manual without TPS’ express written consent and may only use such information for the care and
operation of the receiver. The information and data in this Manual are a valuable asset of TPS and are
developed by the expenditure of considerable work, time and money and are the result of original
selection, coordination and arrangement by TPS.
Trademarks
Sokkia®, Sokkia® GNSS Receiver, GeoPro, Topcon Integrated Leveling TechnologyTM (TILT), Fence
Antenna® technology, Vanguard TechnologyTM, SiteComm, Quartz Lock LoopTM TopNET®,
MAGNET® Field, Topcon® and Topcon Positioning SystemsTM are trademarks or registered
trademarks of TPS. Windows® is a registered trademark of Microsoft Corporation. The Bluetooth®
word mark and logos are owned by Bluetooth SIG, Inc. and any use of such marks by Topcon
Positioning Systems, Inc. is used under license. Other product and company names mentioned herein
may be trademarks of their respective owners.
Disclaimer of Warranty
EXCEPT FOR ANY WARRANTIES IN AN APPENDIX OR A WARRANTY CARD ACCOMPANYING THE
PRODUCT, THIS MANUAL AND THE RECEIVER ARE PROVIDED “AS-IS.” THERE ARE NO OTHER
WARRANTIES. TPS DISCLAIMS ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR USE OR PURPOSE. TPS AND ITS DISTRIBUTORS SHALL NOT BE LIABLE
FOR TECHNICAL OR EDITORIAL ERRORS OR OMISSIONS CONTAINED HEREIN; NOR FOR
INCIDENTAL OR CONSEQUENTIAL DAMAGES RESULTING FROM THE FURNISHING,
PERFORMANCE OR USE OF THIS MATERIAL OR THE RECEIVER. SUCH DISCLAIMED DAMAGES
INCLUDE BUT ARE NOT LIMITED TO LOSS OF TIME, LOSS OR DESTRUCTION OF DATA, LOSS OF
PROFIT, SAVINGS OR REVENUE, OR LOSS OF THE PRODUCT’S USE. IN ADDITION TPS IS NOT
RESPONSIBLE OR LIABLE FOR DAMAGES OR COSTS INCURRED IN CONNECTION WITH
OBTAINING SUBSTITUTE PRODUCTS OR SOFTWARE, CLAIMS BY OTHERS, INCONVENIENCE, OR
NOTICE
Please read the terms and conditions carefully.

Preface
vP/N: 1030371-01
ANY OTHER COSTS. IN ANY EVENT, TPS SHALL HAVE NO LIABILITY FOR DAMAGES OR
OTHERWISE TO YOU OR ANY OTHER PERSON OR ENTITY IN EXCESS OF THE PURCHASE PRICE
FOR THE RECEIVER.
License Agreement
Use of any computer programs or software supplied by TPS or downloaded from a TPS website (the
“Software”) in connection with the receiver constitutes acceptance of these Terms and Conditions in
this Manual and an agreement to abide by these Terms and Conditions. The user is granted a
personal, non-exclusive, non-transferable license to use such Software under the terms stated herein
and in any case only with a single receiver or single computer. You may not assign or transfer the
Software or this license without the express written consent of TPS. This license is effective until
terminated. You may terminate the license at any time by destroying the Software and Manual. TPS
may terminate the license if you fail to comply with any of the Terms or Conditions. You agree to
destroy the Software and manual upon termination of the use of the receiver. All ownership, copyright
and other intellectual property rights in and to the Software belong to TPS. If these license terms are
not acceptable, return any unused software and manual.
Website; Other Statements
No statement contained at the TPS website (or any other website) or in any other advertisements or
TPS literature or made by an employee or independent contractor of TPS modifies these Terms and
Conditions (including the Software license, warranty and limitation of liability).
Technical Documentation and Utility Software
On the Sokkia Support website (https://us.sokkia.com/sokkia-care-products/sru-sokkia-receiver-
utility), you can download technical documentation, training material, and various utility software to
help you set up and use your Sokkia product. The website also offers registration resources, training,
and technical assistance.
Although the support documentation, firmware and utility software for the Sokkia GRX3 can be found
at the Sokkia Care site, the product registration is done via the myTopcon site/or by using the
myTopcon NOW! app. It is free to create an account and register.
Safety
Improper use of the receiver can lead to injury to persons or property and/or malfunction of the
product. The receiver should only be repaired by authorized TPS warranty service centers.
Miscellaneous
The above Terms and Conditions may be amended, modified, superseded or canceled, at any time
by TPS. The above Terms and Conditions will be governed by and construed in accordance with, the
laws of the State of California, without reference to conflict of laws.

Preface
vi
P/N: 1030371-01
Manual Conventions
This manual uses the following conventions:
Convention Description Example
Bold Menu or drop-down menu selection File > Exit (Click the File menu and click
Exit)
Name of a dialog box or screen From the Connection screen...
Button or key commands Click Finish.
Mono User supplied text or variable Type guest and click Enter.
Italic
Reference to another manual or help document Refer to the Sokkia Reference Manual .
NOTE
Further information to note about system configuration, maintenance or setup.
NOTICE
Supplementary information that can have an adverse affect on system operation,
system performance, data integrity or measurements.
CAUTION
Notification that an action has the potential to result in minor personal injury,
system damage, loss of data or loss of warranty.
WARNING
Notification that an action has the potential to result in personal injury or property
damage.
DANGER
Notification that an action has the potential to result in severe personal injury or
death.

P/N: 1030371-01 1-1
Introduction
The Sokkia GRX3 GNSS receiver is a compact, high-performing integrated GNSS receiver for static
and kinematic land surveying applications. The receiver design includes 226 GNSS channel Vanguard
Technology with Universal Tracking Channels and advanced integrated Fence Antenna technology.
These technologies deliver world class positioning and navigation capability to your application by
tracking signals with multiple frequencies and multi-constellation satellite systems such as GPS,
GLONASS, BeiDou, QZSS, Galileo, NavIC, and SBAS.
To create a future proof, efficient positioning system this receiver combines; GNSS tracking
capabilities, multiple-frequency RTK, DGPS and PPP solutions, extensive communication capabilities,
a built-in 8 GB memory and an integrated internal battery.
Several unique features, including advanced multi-path mitigation, adjustable Phase Locked Loop
(PLL) and Delay Locked Loop (DLL), offer reliable and versatile reception of weak signals even in
degraded signal environments. The receiver also supports Quartz Lock Loop (QLL) technology for
superior GNSS tracking in high-vibration environments.
The GRX3 receiver contains an internal HIMU (Hybrid Inertial Measurement Unit) module. This module
measures tilt angles of the rover receiver. The angle values are used by the software application
MAGNET Field for calculating the true projection of the rover antenna phase center on the ground.
The GRX3 GNSS Receiver offers complete IP67 protection against dust and water ingress, in addition
to superior vibration and shock resistance. The Sokkia communication interface allows you to integrate
GNSS performance and quickly deliver world class positioning and navigation support to your
applications.
Figure 1-1: GRX3 Receiver

Introduction
GRX3 Features 1-2
P/N: 1030371-01
GRX3 Features
The GRX3 GNSS receiver’s advanced design provides simplified setup and maximum performance.
The GRX3 receiver features are as follows:
●226 GNSS channel Vanguard Technology with Universal Tracking Channels for multi-frequency
tracking of multiple satellite constellations such as GPS, GLONASS, BeiDou, QZSS, Galileo,
NavIC, and SBAS.
●Industry leading Fence Antenna technology
●Internal, non-removable battery
●Internal UHF radio modem
●Optional Multi-band 4G/3G/2G internal cellular module
●Integrated Bluetooth, multi-channel SiteComm technology
●Interface for controlling and viewing data logging through the LED display
●Topnet Live Starpoint (Pro) global Precise Point Positioning (PPP) correction service
●TILT—Topcon Integrated Leveling Technology
●External power, USB and serial-data ports
●External GNSS antenna connector for GRX3 series receivers without an internal cellular module
●External cellular module antenna connector for GRX3 series receivers with an internal cellular
module
●Internal 8 GB memory storage
●Virtual serial port via USB
●Data access using USB
The GRX3 comes in one of the following configurations:
●No cellular module
●Integrated 4G/LTE cellular module only
●R2 Lite UHF radio, with integrated 4G/LTE cellular module
●Alinco UHF radio (available in Japan)
●Alinco UHF radio (available in Japan), with integrated 4G/LTE cellular module

Introduction
Unpacking Your Receiver Kit
1-3 P/N: 1030371-01
Unpacking Your Receiver Kit
This section describes the documentation, standard kit components1 and accessories that
accompany your receiver. When you unpack your receiver kit, verify that you received the items listed
in this section. If any items are missing or damaged, contact your local Sokkia dealer. See “Getting
Technical Support” on page 1-4.
Standard Kit Components
Table 1-1 lists the standard kit components for the GRX3. For more information about the included
cables, see “Cables” on page 2-6.
Accessories
Sokkia offers a wide variety of accessories specially designed to improve system flexibility and job
site efficiency. For more details on the optional accessories available for GRX3, contact your Sokkia
dealer.
Table 1-2 lists the accessories available for the GRX3. For more information about accessories, see
“Accessories” on page 2-8.
1. Components in the standard kits may differ based on your country or region. Contact your local Sokkia dealer to
inquire about items included in your regional standard kit and accessories that are available with the receiver.
Table 1-1. GRX3 Standard Kit Components
GRX3 Receiver Power Cable
Power Adapter Wall Charger Cable
Micro-USB Cable Serial Cable
GRX3 GNSS Receiver Quick
Reference Card (P/N 1030648-01)
– Describes the LED behavior and
technical content.
Warranty Card
Radio Antenna Cellular Antenna (with cellular variants only)
Table 1-2. GRX3 Accessories
Radio Antenna Rover Pole
External Antenna Cable Prism
External Cellular Antenna Fixed Height Heavy Duty Tripod
Rover Pole Offset Adapters Economy Tripod
Tribrach with Plug Adapter Tape Measure
Hand-Held Controller and Brackets Prism Adapter

Introduction
Technical Documents 1-4
P/N: 1030371-01
Technical Documents
The following documents will help you set up and use your new receiver.
●GRX3 GNSS Receiver Operator’s Manual (this document)—contains detailed information on how
to use your new receiver. You can download the document from the Sokkia Care support site
(https://us.sokkia.com/sokkia-care).
●GRX3 GNSS Receiver Quick Reference Card (P/N 1030648-01)—contains basic hardware and
LED descriptions, along with safety and regulatory statements. This guide is available in your
standard kit package.
●Sokkia Receiver Utility (SRU) Help —an on-screen help document embedded in the software that
contains detailed information on how to use the SRU software. For more information about the
SRU software, see "Using Sokkia Software With Your Receiver".
Using Sokkia Software With Your Receiver
Use the GRX3 receiver in conjunction with the Sokkia Receiver Utility (SRU) and MAGNET Field data
collection software or Pocket 3D machine control system applications for a precision positioning
solution. Sokkia software enables you to configure the receiver and other external devices, manage
files, collect data and perform survey and construction work flows.
The Sokkia Receiver Utility (SRU) is a software program that enables users to configure and update
their GNSS receivers and peripheral devices. You can install it on desktop computers and data
controllers. You can download this program from Sokkia Care (https://us.sokkia.com/sokkia-care).
The help document for SRU is embedded in the software.
Topcon’s MAGNET Field and Sokkia GeoPro Field software for data controllers provides real-time
communication, cloud storage, data collection and exchange and field solutions—such as
topographic staking, roads, calculations and more.
Pocket 3D is a machine control system application for the survey and construction markets. The
software runs on data controllers with Windows CE and mobile platforms. Pocket 3D simplifies data
collection, allowing you to check cuts and fills, layout points and survey all or part of the job site
quickly and efficiently.
Contact your Sokkia dealer for more information about Sokkia field data collection software for the
surveying and construction markets.
Getting Technical Support
Before contacting a Sokkia customer representative about any problems with the receiver, see
“Troubleshooting” on page 8-1 for some solutions that may fix the issue.
Contact your local Sokkia dealer or visit Sokkia Care (https://us.sokkia.com/sokkia-care) for
technical support.
When contacting Sokkia for technical assistance, provide the following information for better and
faster service:
NOTICE
For quick and effective support, provide a detailed description of the problem.

Introduction
Getting Technical Support
1-5 P/N: 1030371-01
1. A description of the following:
■The field operation that was being performed when the problem occurred.
■Details of the unexpected behavior, symptoms and any error messages that precede or follow
the problem.
■Problem occurrence frequency or patterns.
2. Gather your receiver information and configuration settings. To obtain the receiver information:
a. Install SRU on a hard drive of a field controller or personal computer.
b. Use a serial or USB cable for connection.
c. Run SRU, switch on the receiver.
d. Select Device > Application Mode > Receiver Managing.
e. Select Device > Connect.
f. Click the Connect button on the Connection Parameters screen to establish a
communication to the receiver.
g. Click Information on the Main menu of SRU.
The Receiver Info screen opens (Figure 1-2). It displays basic receiver information, such as
hardware and firmware versions, RAM size, receiver ID, serial number and so forth.
h. Click Save to File.
Figure 1-2: Save Receiver Info to File

Introduction
Getting Technical Support 1-6
P/N: 1030371-01
i. Enter a File name and click Save on the Save As window to save it to your computer.
Figure 1-3: Save Receiver Info
3. Specifications of mobile devices and computers used in the field or office exhibiting the
problem. These specifications should include model information, version number, operating
system information, memory and storage capacity.
4. Information about the system software, including the version number and steps to reproduce
the problem.
5. A description of the field environment and/or observation conditions when the problem
occurred.
Website
The Sokkia website provides current information about Sokkia’s line of products. The support area
of the website provides access to Sokkia field and office software, manuals and frequently asked
questions. To access the Sokkia corporate website, visit https://sokkia.com.
The Sokkia Care support and training website provides support for Sokkia registered users. Sokkia
Care provides information about Sokkia products, training, events, firmware and software updates
and troubleshooting procedures. To access this content visit https://us.sokkia.com/sokkia-care.
GRX3 GRX3

Receiver Enclosure—Overview P/N: 1030371-01 2-1
Getting Acquainted
The GRX3 receiver enclosure is fully sealed and may incorporate a GNSS receiver board, multiple
modems, multiple antennas, a battery, memory storage and wireless communication modules that are
enclosed in a rugged housing. The upper part of the receiver includes both GNSS and Bluetooth
antennas that are covered by a Radome and is securely surrounded by a shock absorbing rubber
bumper.
Receiver Enclosure—Overview
Currently, there are five (5) configurations of the GRX3:
●No radio, no cellular module
●R2 Lite UHF radio
●R2 Lite UHF radio, with integrated 4G/LTE cellular module
●Alinco UHF radio (available in Japan)
●Alinco UHF radio (available in Japan), with integrated 4G/LTE cellular module
Figure 2-1 shows a GRX3 GNSS receiver without radio modems or a cellular module (P/N 1028556-
02). The lower part of the receiver contains the External GNSS antenna connector. The Reset button
is located under the SIM card door in the lower part of the receiver.
Figure 2-1: GRX3 without Radio Modems or a Cellular Module
1. Reset button 3. External GNSS antenna connector
2. SIM card door
2
3
1

Getting Acquainted
Receiver Enclosure—Overview 2-2
P/N: 1030371-01
Figure 2-2 shows a GRX3 GNSS receiver with an R2 Lite UHF modem (P/N 1028556-01) and
without a cellular module. The upper part of the receiver includes a connector for the radio modem
antenna. The lower part of the receiver contains the external GNSS antenna connector. The Reset
button is located under the SIM card door in the lower part of the receiver.
Figure 2-2: GRX3 with a UHF Without a Cellular Module
Figure 2-3 shows a GRX3 GNSS receiver with an R2 Lite UHF modem (P/N 1028556-05) and with a
cellular module. The upper part of the receiver includes a connector for the radio modem antenna.
The lower part of the receiver contains the external cellular module antenna connector. The Reset
button and SIM card slot are located under the SIM card door in the lower part of the receiver.
Figure 2-3: GRX3 with a UHF With a Cellular Module
1. Reset button 3. External GNSS antenna connector
2. SIM card door 4. External radio modem antenna connector
2
3
1
4
1. Reset button 4. External cellular module antenna connector
2. SIM card slot 5. External radio modem antenna connector
3. SIM card door
3
4
5
2
1

Getting Acquainted
Receiver Enclosure—Overview
2-3 P/N: 1030371-01
Receiver Enclosure—Display Panel
The receiver’s lower part is made of a magnesium alloy and contains a display panel.
Figure 2-4: Lower Part of Receiver—Display Panel
The display panel enables you to view the receiver’s operational status. For more information about
the display panel’s operational status see “Display Panel” on page 3-1.
Receiver Enclosure—SIM Card Door
The SIM card door (Figure 2-5 on page 2-4) is located to the left of the LED Display Panel. To remove
the SIM card door from the GRX3 use a flat blade screwdriver and remove the two screws. The
Reset button is located under the SIM card door. For the GRX3 receivers with cellular module(s)
installed, the SIM card slot is located there, too.
1. Power button 2. Display panel
1
2
NOTICE
The GRX3 receiver’s GSM functionality is enabled when the Micro-SIM Card is
installed.
NOTICE
Cellular operation is based on subscribed services.
NOTICE
The SIM Card usually remains inside the receiver.

Getting Acquainted
Receiver Enclosure—Overview 2-4
P/N: 1030371-01
The cellular module with SIM card installed is accessed via MAGNET Field, Magnet Construct or SRU
for configuration purposes. Additional Micro SIM cards can be purchased by the user.
Figure 2-5: Removing the SIM Card Door
Receiver Enclosure — GRX3 Hardware Reset Button
If the GREX3 receiver stops responding via the Power button (Figure 2-4 on page 2-3) or the external
software—perform a hardware reset. A hardware reset should only be performed when the GNSS
receiver is powered on and not otherwise responding.
To perform a hardware reset:
1. Remove the SIM Card Door using a flat blade driver to remove the two screws (Figure 2-5).
2. Insert a paper clip or any pointed stick small enough to fit into the pinhole of the Reset Button.
3. Gently press the Reset Button for about one second until the GRX3 powers off.
4. After the Reset Button is released, the GNSS receiver is automatically powered on.
5. Close the SIM Card Door and install the two screws.
1. Reset button 3. SIM card door
2. SIM card slot (optional) 4. Screw (2)
3
2
4
1
WARNING
A hardware reset does not erase the “*.tps” data file(s) stored in the receiver’s
internal memory and does not change the user’s settings entered in to the
receiver.

Getting Acquainted
Receiver Enclosure—Overview
2-5 P/N: 1030371-01
Receiver Enclosure—Bottom Overview Labels
Attached to the bottom of the receiver enclosure are the regulatory and product identification labels.
The product identification label contains the serial number (S/N) and part number (P/N)
(Figure 2-6) for the receiver.
Figure 2-6: Bottom Enclosure Overview with Product Identification and Regulatory Labels
1. Reset button 3. SIM card door
2. SIM card slot (optional) 4. Screw (2)
1. Regulatory label 3. Serial number
2. Part number 4. Product identification label
1
3
4
2

Getting Acquainted
Cables 2-6
P/N: 1030371-01
Cables
The GRX31 package includes a power supply cable, a USB cable and a power adapter. Table 2-1
describes the cables included with your receiver—depending on your regional standard kit
configuration. Make sure to contact your local Sokkia dealer to inquire about standard items included
in your receiver kit.
1. Components in the standard kit may differ based on your region. Contact your local Sokkia dealer to inquire about
items included in your regional standard kit and accessories that are available with the receiver.
NOTE
Align the keyways when connecting the power/serial cable to the receiver
connectors. To disconnect the cable, push the cable in and then gently remove the
cable.
Table 2-1. Receiver Cables
Cable Description Cable Illustration
Power Charge Cable(s)
These two cables connect to the power
adapter to a grounded outlet. Several
options are available for the power charger
cable based on your country. To purchase
this cable, contact your Sokkia dealer.
Refer to this part numbers:
P/N 1005793-01 - Cable, Power Charger
(US)
P/N 1005794-01 - Cable, Power Charger
(EUR)
P/N 1021180-01 - Cable, Power Charger
(AUS)
See Figure 2-7 on page 2-7 and
Figure 2-8 on page 2-7.
Receiver Power/Charging Cable
Connects the receiver and the power
supply unit via SAE connectors for battery
charging.
P/N 14-008016-04LF
Micro-USB Cable
Connects the receiver to an external
device (controller or computer) for data
transfer and receiver configuration.
P/N 1013602-01
Serial Cable
Connects the receiver to an external
device (controller or computer) for data
transfer and receiver configuration.
P/N 14-008005-03