Trimble SPS852 Getting Started Manual

i

GETTING STARTED GUIDE

Trimble SPS852 Modular GPS

Receiver

Version 4.15
Revision A
April 2010

SPS852 Getting Started Guide

ii

Table of Contents

Introduction ........................................................................................................................................................... 3

Related information .......................................................................................................................................... 3

Technical support ............................................................................................................................................. 3

Your comments ................................................................................................................................................ 3

Safety Information ................................................................................................................................................ 5

Use and care ..................................................................................................................................................... 5

Regulations and safety ..................................................................................................................................... 5

Type approval .................................................................................................................................................. 5

Exposure to radio frequency radiation ............................................................................................................. 5

Installing a ntennas ............................................................................................................................................ 7

Battery safety ................................................................................................................................................... 7

Changing the Radio module ............................................................................................................................. 8

Wet locations .................................................................................................................................................... 8

Use of Power over Ethernet ............................................................................................................................. 9

Batteries and Power ............................................................................................................................................ 10

Battery safety ................................................................................................................................................. 10

Charging the Lithium-ion batt e ries ................................................................................................................ 10

SPS Modular with internal battery only ......................................................................................................... 11

Using the Lithium-ion battery as a Universal Power Supply (UPS) .............................................................. 11

Removing the rechargea ble Lithium-ion battery ............................................................................................ 11

Storing the Lithium-ion battery ...................................................................................................................... 11

Power over Ethernet (PoE) ............................................................................................................................. 12

External power ............................................................................................................................................... 12

Keypad and display ............................................................................................................................................. 14

Button operations ................................................................................................................................................ 15

Power button operations ..................................................................................................................................... 16

Home screen ....................................................................................................................................................... 17

Status screens ...................................................................................................................................................... 19

Radio status .................................................................................................................................................... 19

Configuring system settings ................................................................................................................................ 20

Turning off AutoBase technology .................................................................................................................. 21

SPS852 signal tracking ....................................................................................................................................... 22

Managing application files .................................................................................................................................. 23

Default Settings ................................................................................................................................................... 24

Default receiver settings ................................................................................................................................. 24

Resetting the receiver to factory defaults ....................................................................................................... 24

Default behavior ............................................................................................................................................. 25

Logging data .................................................................................................................................................. 25

Adding Radio Frequencies .................................................................................................................................. 26

Adding receive frequencies for the 450 MHz internal receive radio .............................................................. 26

Setting UHF reception radio frequencies using the web interface ................................................................. 28

Troubleshooting .................................................................................................................................................. 29

Glossary .............................................................................................................................................................. 30

Legal Notices ...................................................................................................................................................... 35

3

Introduction

Trimble SPS852 Modular GPS receivers are ideal for the following site development and
construction applications:

• Base station for precision GPS applications such as site positioning and machine control

• Location RTK for site vehicle and supervisors

• Precision RTK rover on-site

• System integrator applications using Location GPS augmentation, including OmniSTAR,

Location RTK, SBAS, and DGPS RTCM and Precision RTK

The receiver has a keypad and display, so you can configure the receiver without using a controller or
computer.

All the receivers can optionally record GPS data to the internal memory, and transfer the data over a
serial or Ethernet connection.

Related information

Sources of related information include the following:

• Release notes – The release notes describe new features of the product, information not included

in the manuals, and any changes to the manuals. They can be downloaded from the Trimble
website (www.trimble.com/support.shtml).

• Trimble training courses – Consider a training course to help you use your GPS system to its

fullest potential. For more information, go to the Trimble website at

www.trimble.com/training.html.

Technical support

If you have a problem and cannot find the information you need in the product documentation,
contact your local dealer. Alternatively, go to the Support area of the Trimble website
(www.trimble.com/support.shtml). Select the product you need information on. Product updates,
documentation, and any support issues are available for download.

If you need to contact Trimble technical support, complete the online inquiry form at

www.trimble.com/support_form.asp.

Your comments

Your feedback about the supporting documentation helps us to improve it with each revision. Email
your comments to [e-mail].

5

Safety Information

Before you use your Trimble product, make sure that you have read and understood all safety
requirements.

Use and care

This product is designed to withstand the rough treatment and tough environment that typical ly
occurs in construction applications. However, the receiver is a high-precision electronic instrument
and should be treated with reasonable care.

Caution – Operating or storing the receiver outside the specified temperature range can damage it.

Regulations and safety

Some SPS receiver models with base station capability contain an internal radio-modem for
transmission or can transmit through an external data communications radio. Regulations regarding
the use of the 410 MHz - 470 MHz radio-modems vary greatly from country to country. In some
countries, the unit can be used without obtaining an end-user license. Other countries require end­user licensing. For licensing information, consult your local Trimble dealer.

All SPS receiver models are capable of transmitting data through Bluetooth wireless technology.
Bluetooth wireless technology, and 900 MHz

1 radio-modems (and 2.4 GHz radio-modems - Japan

only) operate in license-free bands.

Before operating a Trimble GPS receiver or GSM modem, determine if authorization or a license to
operate the unit is required in your country. It is the responsibility of the end user to obtain an
operator's permit or license for the receiver for the location or country of use.

For FCC regulations, see Legal Notices.

Type approval

Type approval, or acceptance, covers technical parameters of the equipment related to emissions that
can cause interference. Type approv al is granted to the manufacturer of the transmission equipment,
independent from the operation or licensing of the units. Some countries have unique technical
requirements for operation in particular radio-modem frequency bands. To comply with those
requirements, Trimble may have modified your equipment to be granted Type approval.

Unauthorized modification of the units voids the Type approval, the warranty, and the operational
license of the equipment.

Exposure to radio frequency radiation

For 450 MHz radio

Safety. Exposure 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:

SPS852 Getting Started Guide

6

• DO NOT operate the transmitter when someone is within 20 cm (7.8 inches) 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.

For license-free 900 MHz radio1

Caution – For your own safety, and in terms of the RF exposure requirements of the FCC,
always observe the precautions listed here.

• DO NOT operate the transmitter when someone is within 20 cm (7.8 inches) of the antenna.

• DO NOT co-locate the antenna with any other transmitting device.

For 2.4 GHz radio2

Safety. Exposure 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 20 cm (7.8 inches) of the antenna.

The maximum gain of the antenna must not exceed 8 dBi.

For Bluetooth radio

The radiated output power of the internal Bluetooth wireless radio is far below the FCC radio
frequency exposure limits. Nevertheless, the wireless radio shall be used in such a manner that the
Trimble receiver is 20 cm or further from the human body. The internal wireless radio operates
within guidelines found in radio frequency safety standards and recommendations, which reflect the
consensus of the scientific community. Trimble therefore believes that the internal wireless radio is
safe for use by consumers. The level of energy emitted is far less than the electromagnetic energy
emitted by wireless devices such as mobile phones. However, the use of wireless radios may be
restricted in some situations or environments, such as on aircraft. If you are unsure of restrictions,
you are encouraged to ask for authorization before turning on the wireless radio.

For GSM/GPRS radio

Safety. Exposure 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 28 cm (11 inches) of the antenna.

All equipment should be serviced only by a qualified technician.

Glossary

7

Installing antennas

Caution – For your own safety, and in terms of the RF exposure requirements of the FCC,
always observe these precautions:
– Always maintain a minimum separation distance of 20 cm (7.8 inches) between yourself and
the radiating antenna .
– Do not co-locate the antenna with any other transmitting device.

Warning – The GPS antenna and its cabling should be installed in accordance with all national
and local electrical codes, regulations, and practices.

The antenna and cabling should be installed wher e they will not become energiz e d as a result of
falling nearby power lines, nor be mounted where they are subjected to over-voltage transients,
particularly lightning. Such installations require additional protect ive means that are detailed in
national and local electrical codes.

Trimble SPS internal radios have been designed to operate with the antennas listed below. Antennas
not included in this list are strictly prohibited for use with this device. The required antenna
impedance is 50 ohms.

The antennas that can be used (country dependent) with the 450 MHz radio are 0 dBi and 5 dBi whip
antennas. The antennas that can be used (country dependent) with the 900 MHz radio are 0 dBi, 3
dBi, and 5 dBi whip antennas. The antennas that can be used (country dependant) with the 2.4 GHz
radio are 2 dBi and 8 dBi whip antennas.

To reduce potential radio interference to other users, the antenna type and its gain should be so
chosen so that the equivalent isotropically radiated power (e.i.r.p.) is not more than that permitted for
successful communication.

Battery safety

SPS receiver internal lithium-ion battery

WARNING–Do not damage the rechargeable Lithium-ion battery. A damaged battery can cause an
explosion or fire, and can result in personal injury and/or propert y damage.
To prevent injury or damage:
– Do not use or charge the battery if it appear s to be damaged. Signs o f damage include, but are not
limited to, discoloration, warpi ng, and leaking battery fluid.
– Do not expose the battery to fire, high temperature, or dir ect sunlight.
– Do not immerse the battery in water.
– Do not use or store the battery inside a vehicle during hot weather.
– Do not drop or puncture the battery.
– Do not open the battery or short-circuit its contacts.

WARNING – Avoid contact with the recharge able Lithi um-ion batte ry if it appea r s to be lea king.
Battery fluid is co rrosive, and contact with it can result in personal injury and/or property damage.
To prevent injury or damage:
– If the battery leaks, avoid contact with the battery fluid.
– If battery fluid gets into your eyes, immediately rinse y our eyes with clean water and se ek medical
attention. Do not rub your eyes!
– If battery fluid gets onto yo ur skin or clothing, i mmediately use clean water to wash off t he battery
fluid.

SPS852 Getting Started Guide

8

WARNING – Charge and use the rechargeable Lithium-ion battery only in strict accordance with the
instructions. Charging or using the battery i n unauthori zed equipment can cause an explosion or fire,
and can result in personal injury and/or equi pment damage.
To prevent injury or damage:
– Do not charge or use the bat tery if it appears to be damaged or leaking.
– Charge the Lithium-ion battery only in a Trimble product that is specified to charge it. Be sure to
follow all instructions th at are provided with the battery charger.
– Discontinue charging a battery that gives off extreme heat or a burning odor.
– Use the battery only in Trimble equipment that is specified to use it.
– Use the batte ry only for its intended use and according to t he instructions in the product
documentation.

Connecting SPS receivers to a vehicle battery

WARNING – Use caution when connecting battery cable's clip leads to a vehicle battery. D o n ot allow
any metal object or jew elry to connect (short) the battery's positive (+) terminal to either the negative (-)
terminal or the metal of the veh icle connected to the bat tery. This could result in high current, arcing,
and high temperatures, exposing the user to poss ible injury.

WARNING – When connecting an external battery, such as a vehicle battery, to an SPS receiver, be sure
to use the Trimble cable with proper over-current protect ion intended for this purpose, to avoid a safety
hazard to the user or damage to the product.

Changing the Radio module

Trimble requires that you do not change from one version of a radio door assembly to another, for
the following reasons:

• The regulatory compliance requirements will be violated. Operating such a product is illegal.

• The internal connector on the radio is not intended for multiple insertions or extractions. It may

be damaged or break if overused.

• The seal integrity of the whole GPS receiver is compromised when the radio is removed. Users

do not have the facilities to test the integrity of the seal.

If the unit is outside of warranty, you can purchase another radio door, which must be installed
by a Trimble authorized Service Provider. There are hardware limitations to this, so be very
careful, especially with the 900 MHz doors.

Caution – Because of installation problems and country regulation issues, Trimble does not sell
radio doors to end users. Trimble authorized Service Providers must comply with country
regulations and install the correct radio only in defined and accepted receivers. Installing a
radio in a non-specified GPS product or device voids any warranty of the radio and of the GPS
product. It also subjects the service provider to penalties set forth by various government
agencies. Trimble shall assume no liability for radios used in non-authorized products.

Wet locations

WARNING – This product is not int ended to be used outdoors or in a wet location when it is powered by the
PoE interface, or by the external power supply.

WARNING – The exter nal power adaptor and its associat ed power c o r d and plug are not intended to be
installed outdoors, or in a wet location.

Glossary

9

Use of Power over Ethernet

WARNING – When this product is connected to a Power over Ethernet c onnection, the source of the Eth ernet
power must meet IEEE 802.11af, and its DC output (Ethernet power source) must be completely isolated from
earth ground (floating), or a shock hazard may exis t .

WARNING – The external power adaptor and its asso ciated power cord and plug are not intended t o be
installed outdoors, or in a wet location.

1. 900 MHz radios are not used in Eu r ope.

2. 2.40 GHz radios a r e a vailable initially only for Japan.

SPS852 Getting Started Guide

10

Batteries and Power

The receiver has one internal recha rg eabl e Lith ium -ion battery.
The operational time provided by the internal battery depends on the type of measurement and

operating conditions. Typically, the internal battery provides 10 hours operation as a base station and
12 hours as a rover during measurement operations using the internal radio.

The receiver can also be powered by an external power source that is connected to the Lemo or
modem port.

All battery operation tests are carried out with new, fully-charged batteries at room temperature and
with full receiver configuration operational. Older batteries, at temperatures significantly higher or
lower than room temperature, will have a reduced performance. Receivers operating with reduced
configuration will have a higher performance.

Battery safety

Charge and use the battery only in strict accordance with the instructions provided.

WARNING – Do not damage the rechargeable Lithium-ion b attery. A damaged battery can cause an explosion
or fire, and can result in personal injury and/or property damage.
To prevent injury or damage:
– Do not use or charge the batte ry if it appears to be damaged. Signs of damage include, but a re not limited to,
discolorat ion, warping, and leaking battery fluid.
– Do not expose the battery to fire, high temperature, or direct sunlight.
– Do not immerse the battery in water.
– Do not use or store the battery inside a vehicle during hot weather.
– Do not drop or puncture the battery.
– Do not open the battery or short-circuit its contacts.

WARNING – Avoid contact with the rechargeable Lithium-ion battery if it appea rs to be leaking. Battery fluid
is corrosive, and contact with it can result in personal i njury and/or property da mage.
To prevent injury or damage:
– If the battery leaks, avoid contact with the battery fluid.
– If battery fluid gets into your eyes, immediately rinse y our eyes with clean water and se ek medical attention.
Do not rub your eyes!
– If battery fluid gets onto yo ur skin or clothing, i mmediately use clean water to wash off t he battery fluid.

Connecting SPS receivers to a vehicle battery

WARNING – Use caution when connecting battery cable's clip leads to a vehicle battery. Do not allow any
metal object or jewelry to connect (short) the battery's positive (+) terminal to either the negative (-) terminal
or the metal of the vehicle connected to the battery. This co uld result in high current, arcing, and high
temperatures, exposing the user to possible injury.

WARNING - When connecting an external battery, such as a vehi cle battery, to an SPS receiv er, be sure to use
the Trimble cable with proper over-current protection intended for this purpose, to avoid a safety hazard to
the user or damage to the product.

Charging the Lithium-ion batteries

The rechargeable Lithium-ion batteries are supplied partially charged. Charge the battery completely
before using it for the first time. If the battery has been stored for longer than three months, charge it
before use.

Glossary

11

Warning – Charge and use the rechargeable Li t hi um-ion battery only in strict accordance w ith the
instructions. Charging or using the battery i n unauthori zed equipment can cause an explosion or fire,
and can result in personal injury and/or equi pment damage.
To prevent injury or damage:
– Do not charge or use the battery if it appears to be damaged or leaking.
– Charge the Li thium-ion battery only in a Trimble product that is specified to charge it. Be sure to
follow all instructions th at are provided with the battery charger.
– Discontinue charging a battery that gives off e xtreme heat or a burning odor.
– Use the battery only in Trimble equipment that is specified to use it.
– Use the batte ry only for its intended use and according to t he instructions in the product
documentation.

SPS Modular with internal battery only

The internal battery charges fully in 8 hours when connected to a suitable power source.
When the internal temperature of the receiver is greater than 50 °C (122 °F) or less than 5 °C (41 °F),

the internal battery charger stops charging and the receiver’s display shows Charger Disabled, Tem p
Limited. However, the receiver will still draw its power from the external DC source, extending the
operating time in the field.

When the external DC voltage is not able to support the power drain, an X is displayed across the
battery status icon on the front panel display, which indicates that the internal charger is off.

Using the Lithium-ion battery as a Universal Power Supply (UPS)

The internal battery will only charge from an external power source as long as that source can
support the power drain, for example, an AC power adaptor. The receiver is supplied with an AC
power (also known as mains power) supply unit that recharges the battery inside the receiver when it
is connected through the adaptor to the modem port or the Lemo port. When you use the receiver on
large projects, from a permanent or semi-permanent base station location in a site trailer, Trimble
recommends that you use this power supply at all times to keep the internal battery charged. This
provides an uninterrupted power supply and will keep the site operational for more than 10 hours
after a power failure.

Keep all batteries on continuous charge when not in use. You can keep batteries on charge
indefinitely without damage to the receiver or to the batteries.

Removing the rechargeable Lithium-ion batter y

The internal Lithium-ion battery should be removed only at an authorized Trimble Service Center. If
the battery is removed at an unauthorized service center, the remaining warranty on the product will
be void.

Storing the Lithium-ion battery

If you must store a Lithium-ion battery for long periods, make sure that it is fully charged before it is
stored, and that you charge it at least once every three months while it is stored.

Do not allow a battery that is in storage to discharge to below 5 V. A battery that reaches deep
discharge level (5 V or less) cannot be recharged and must be replaced. To protect a battery that is in
use from deep discharge, the receiver switches power sources or stops drawing power when the
battery pack discharges to 5.9 V.

SPS852 Getting Started Guide

12

All batteries discharge over time when not in use, and they discharge faster in colder temperatures.
Do not store the receiver at temperatures outside the range –40 °C to +70 °C (–40 °F to +158 °F).

Power over Ethernet (PoE)

The receiver is a PoE-capable device and can be powered using a single Ethernet cable from an
IEE802.3af capable network using one of the following cables/adaptors:

• 57168

• 65791-00, 78235-00

Warning – This product is not intended to be used outdoors or in a wet location whe n it is powered by
the POE inter face, or by the external power supply. The product should only be used in these types of
environments when ope rating on its own intern a l battery.

Warning – When t hi s product is connected to a PoE connection, the source of the Ethernet power must
meet IEEE 802.11af, and its DC output (Ethernet power source) must be completely isolated from earth
ground (floating), or a shock hazard may exist.

External power

Sources of external power include:

• AC power

• 12 V car or truck battery

• Trimble custom external battery pack

• Generator power

• Solar panel

The GPS receiver uses an external power source in preference to its internal batteries. If the receiver
is not connected to an external power source, or if the external power supply fails, the internal
batteries are used.

While carrying out static measurements for postprocessed computations using the internal memory, if
no external power is supplied and the internal battery is drained, the receiver shuts down. No data is
lost and when power is restored, the receiver restarts in the same status as it was when power was
lost.

It is possible to turn off the internal battery using the web interface. In this case, when external power
is switched off, there is a limited time (30 seconds) before the unit turns off.

Supported power cables

Part
Number

SPS
connection

Power
connection

Power Source Other connectors

46125-20 7-pin Lemo 'Croc' clips

Power from 12 V car
battery

None

56653-10 26-pin Adapter with Hirose

Power from SPS700 total
station battery cradle
system

None

59044 7-pin Lemo Cable with DC plug

Power to host devices
from AC adapter

Serial

Glossary

13

67384 7-pin Lemo Cable with DC plug

Power to host devices
from AC adapter

Serial to serial for Moving
Base applications

57167 26-pin

Adapter with DC
plug

Power from AC adapter

USB(B) socket and Ethernet
socket

57168 26-pin

Adapter with DC
plug

Power from AC adapter Serial and Ethernet socket

60789-00,
77070-00

26-pin Cable with DC plug Power from AC adapter

2 x Serial, Ethernet plug,
USB(A) plug, 1PPS (BNC)

65791-00,
78235-00

26-pin Cable with DC plug Power from AC adapter 2 x Serial, Ethernet socket

Note – SPS852 low voltage cut-offs:
Power applied through the Lemo connector models a standard 12.4 V lead acid battery. Shut-down

voltage is temperature-compensated and is designed to prolong the life of a lead acid battery and not
place it into a deep discharge state.

Power applied through the 26-pin adaptor cable models a standard 11.1 V lithium-ion battery. Shut­down voltage is temperature-compensated and is designed to prolong the life of a lithium-ion battery.

The external DC voltage supply can be used by the receiver if it is in the range stated by the label on
the receiver.

Connecting SPS receivers to a vehicle battery

WARNING – Use caution when connecting battery cable's clip leads to a vehicle battery. Do not allow any
metal object or jewelry to connect (short) the battery's positive (+) terminal to either the negative (-) terminal
or the metal of the vehicle connected to the battery. T his could result in high current, arcing, and high
temperatures, exposing the user to possible injury.

WARNING – When connecting an external battery, such as a vehicle battery, to an SPS receiver, ensure that
you use the Trimble cable with proper over-current prot ection intended for thi s purpose, to avoid a safety
hazard to the user or damage to the product.

SPS852 Getting Started Guide

14

Keypad and display

Feature

Description

1 Power button Indicates if the receiver is turned on or off.
2

Buttons Used to turn on and configure the receiver.

3 Display

The receiver has a Vacuum Fluorescent Display that enables you to see how the
receiver is operating and view the configuration settings.

4

Bluetooth
antenna

Location of the Bluetooth antenna.

Glossary

15

Button operation s

Use the buttons on the front panel to turn the receiver on and off and to check or change the receiver
settings.

Button

Name

Function

Power

Turns the receiver on and off and performs reset operations.

Escape

Returns to the previous screen or cancels changes being made on a
screen.

Enter Advances to the next screen or accepts changes made on a screen.

Up

Moves the cursor between multiple fields on a screen or makes
changes to an editable field.

Down

Moves the cursor between multiple fields on a screen or makes
changes to an editable field.

Left Moves the cursor between characters in a field that can be changed.

Right

Moves the cursor between characters in a field that can be changed.
Press this button to enter Edit mode.

SPS852 Getting Started Guide

16

Power button oper a t ion s

Press the Power button to turn the receiver on and off. In addition, you can tap to return to the
Home screen, or hold down

to perform the following operations:

To …

Hold the

button

for …

Notes

turn off the receiver two seconds

The display shows a countdown timer. When the display goes
blank, release the Power button.

clear the almanac,
ephemeris, and SV
information

15 seconds

The display show a countdown timer. When the display goes
blank, continue to hold the Power button. The display shows a
countdown time to clear the almanac and ephemeris. When the
counter reaches 0, release the Power button.

reset the receiver to
its factory defaults
and the default
application file

35 seconds

The display show a countdown timer. When the display goes
blank, continue to hold the Power button. The display show a
countdown to clear the almanac and ephemeris. When the
counter reaches 0, continue to hold the Power button. The display

indicates a countdown to resetting the receiver. When the counter

reaches 0, release the Power button.

force the receiver to
power down

at least 60 seconds

If the reset m

ethod above does not work, use this method to force

the receiver to turn off. When the Power LED goes off, release the

Power

button.

Glossary

17

Home screen

The Home screen is the main screen displayed on the receiver. If the receiver displays another screen
and is left idle for 60 seconds, you are returned to the Home screen. It shows the following
information:

• Number of satellites being tracked:

• When the receiver is in Base mode, the Home screen displays the number of

satellites in view, that is, all satellites above the elevation mask. This is the number
of satellites that the base station is sending data for:

• When the receiver is in Rover, Heading, or Moving Base mode, the Home screen

displays the number of satellites used to calculate the position:

• If the receiver is set to use SBAS or OmniSTAR corrections, the Home screen displays

the number of satellites that corrections have been received for.

• If the receiver is computing an autonomous solution, the Home screen displays all

satellites in view, that is, all satellites above the elevation mask.

Tip – To view these details using the web interface, select Receiver Status / Position.

• Internal battery power remaining

• Current mode configuration

• Internal radio activity

If the receiver has an internal radio, the Home screen displays the frequency or channel being
used and the transmit/receive status:

• Current Heading

If the receiver is in Heading mode, the Home screen displays the current heading:

SPS852 Getting Started Guide

18

• Beacon status and frequency

If the receiver is using MSK Beacon corrections, the Home screen display s the st atus of the
signal and the frequency of the beacon station:

Glossary

19

Status screens

The receiver has several view-only status screens that allow you to review the current settings of the
receiver. The status screens provide the following information:

• Position solution and precisions

• CMR and RTCM IDs or OmniSTAR satellite and link status

• Base name and code

• Latitude, longitude, and height

• Antenna height

• Horizontal and vertical precision

• Receiver model and hardware version

• Receiver firmware version

• Receiver serial number

• Receiver IP address

To access these screens from the Home screen, press

or .

Radio status

When a radio is installed (either 450 MHz or 900 MHz), the following status messages appear at the
top line of the screen:

Message

Description

Tran Transmitted a frame
Recv Received a fra me

Busy

Frame was blocked

Sync Got sync with base station
Rept Repeated a frame
Sig Got carrier detect
Ovld

Radio bandwidth exceeded (data has probably been lost)

SPS852 Getting Started Guide

20

Configuring system settings

You can use the keypad and display of the receiver to configure the following settings:

• Display language

• Display and input units

• Baud rate, parity, data bits, and stop bits for serial ports

• Display power saver

• AutoBase warning

• Set position precisions

To access the system settings:

1. In the Home screen, press

. Use the Operation Mode screen to configure system settings
or mode settings, and to view the SV (satellite) status. Mode Settings is the default
setting.

2. Press

. When the operation mode begins to flash, the receiver is in Edit mode and you

can change this setting.

3. Press

to change to System Setup.

4. Press

to accept the change.

5. Press

again.

6. Use the Display Language screen, if required, to change the language. Choose English,

Finnish, French, German, Italian, Spanish, or Swedish. Press

to accept the change.

7. Press

again. Use the Display and Input Units screen, if required, to change the units to

Meters or US Feet.

8. Press

to accept the change.

9. Press

again. Use the Port Settings screen, if required, to change the port.

10. Press

to accept the change.

11. Press

again. Use the Screen Pwr Savr screen to choose On, Off, or Auto. If you use the
Auto setting, the screen turns off after 60 seconds of inactivity. The Power LED
remains lit so that you can tell if the receiver is on or off. If an error message appears,

the screen comes back on. Press

to accept the change and then press again to

move to the next screen.

12. If you are using an SPS Modular GPS RTK base station, the Autobase warning screen

appears. See Automatically Setting up a Mobile Base Station Using AutoBase
Technology.

13. Press

to accept the change.

14. Press

again. When the Home screen appears, the system setup is complete.

Glossary

21

Turning off AutoBase technology

You can turn off AutoBase technology using either the receiver’s keypad and display or the web
interface (see Receiver Configuration menu).

When AutoBase technology is off, you can establish a new base station position in the receiver using
the Edit Current or New Base (Here) menus. This does not automatically generate a new application
file, but changes the settings in the current application file. When the receiver is turned on again, the
most recent settings are always used.

To turn off AutoBase technology using the receiver:

1. In the Home screen, press

.

2. Press

. When the operation mode begins to flash, the receiver is in Edit mode and you can

change this setting.

3. Press

to change to System Setup.

4. Press

to accept the change.

5. Press

again. You start to scroll through options in the System Setup menu.

6. Keep pressing

until Autobase appears.

7. Press

. The setting On flashes.

8. Press

until it displays Off. Press to accept the change.

9. Press

again. The Active Appfile screen appears.

Note – If AutoBase is turned on, the AutoBase Warning screen appears.

To change the application file:

• Press

to display START Appfile.

• Press

to show SAVE Appfile.

• Press

to show DELETE Appfile.

• Press

to show START Appfile.

SPS852 Getting Started Guide

22

SPS852 signal tr acking

This table shows the signal tracking capability for the SPS852 receiver.

GPS signal type

Class

SPS852 (Construction)

SPS852 L1 GNSS

GPS signals L1
L2
L2C
L5 Optional
GLONASS signals L1 Optional
L2 Optional
Galileo GIOVE A, B
GPS SBAS corrections WAAS
EGNOS
MSAS

OmniSTAR corrections

XP
HP
GZ
VBS

Beacon corrections MSK

Glossary

23

Managing application files

You can use the front panel to manage application files in the receiver. You can see which
application file the receiver is currently using and then choose to make changes to it and save it, load
a different application file, or delete an application file.

To manage the application files, use the System Setup menu (see the figure below). You can only
manage application files when the AutoBase fea tu re is turned o ff.

To save an application file, configure all the settings you need through the front panel and then save
the file. When you save the file, the receiver provides a default filename, which you can change,
based on the currently set mode. For example:

If the receiver is set to the following mode:

The suggested application filename is:

Base BASE01
Heading HDG01
Moving Base MB01
Rover ROV01

Note – If you start an application file that is saved with AutoBase turned on in the file, then it turns on
AutoBase in the receiver, even if it was off before the file was loaded.

Application fil e handling throug h t he front panel of t he receiver

SPS852 Getting Started Guide

24

Default Settings

All settings are stored in application files. The default application file, Default.cfg, is stored
permanently in the receiver, and contains the factory default settings. Whenever the receiver is reset
to its factory defaults, the current settings (stored in the current application file, Current.cfg) are reset
to the values in the default application file.

You cannot modify the default application file. However, you can create a power-up application file
so that the settings in this file can be applied immediately after the defaul t appl ica tion file, ov err iding
the factory defaults. For more information, see Configuring the receiver using application files.

Default receiver settings

These settings are defined in the default application file.

Function

Settings

Factory default

SV Enable All SVs enabled
General Controls Elevation mask

PDOP mask
RTK positioning mode
Motion

10°
7
Low Latency
Kinematic

Serial Port 3 Baud rate

Format
Flow control

38,400
8-None-1
None

Serial Port (Modem) 2 Baud rate

Format
Flow control

38,400
8-None-1

None
Input Setup Station Any
NMEA/ASCII (all support messages) None

Streamed output

All Types Off

Offset = 00
RT17/Binary All ports Off
OmniSTAR Internal demodulator Off
Antenna Type

Height (true vertical)
Measurement method

Zephyr Geodetic Model 2

0.00 m

Antenna Phase Center

Resetting the receiver to factory defaults

To reset the receiver to its factory defaults, do one of the following :

• On the receiver, press

for 15 seconds.

• In the GPS Configurator software, select Conne c t to Recei ver and then click

Reset Receiver in

the General tab.

• In the Configuration Toolbox software, select the General tab and then click

Reset Receiver.

For more information on the GPS Configurator and Configuration Toolbox software, see Configuring
the Receiver Settings.

Glossary

25

Default behavior

If a power-up application file is present in the receiver, its settings are applied immediately after the
default settings. This means you can use a power-up file to define your own set of defaults. The
factory defaults are also applied when you perform a full reset of the receiver because resetting the
receiver deletes the power-up files.

When starting any of the SPS GPS receivers as a base station or rover receiver using the Trimble
SCS900 site controller software or the HYDROpro software, the settings required for those
operations are automatically set and configured in that software. To chang e the receiv er setting s for
special applications or for use with third-party software, use the GPS Configurator software or the
Configuration Toolbox software.

Logging data

Data logging involves the collection of GPS measurement data over a period of time at a static point
or points, and subsequent postprocessing of the information to accurately compute baseline
information. Data logging using GPS receivers requires access to suitable GPS postprocessing
software such as the Trimble Business Center sof twar e.

Postprocessed GPS data is typically used for control network measurement applications and precise
monitoring. GPS measurement data is collected over a period of time at a static point or points and
then postprocessed to accurately compute baseline information.

By default, the Data Logging option is turned off. For information on how to enable the Data
Logging option, and the required postprocessing software options, contact your Trimble dealer.

Logging data after a power loss

If power is unexpe cte dl y lo st whi le the receiver is logging data, the receiver tries to return to the state
it was in immediately before the power loss. The receiver does not reset itself to default settings.

If the receiver was logging data when power was lost, it resumes logging data when power is
restored.

SPS852 Getting Started Guide

26

Adding Radio Frequencies

If you have the optional internal 450 MHz receive radio in your GPS receiver, use the WinFlash
utility to add the relevant receive frequ encies to the default list of frequencies.

You can also use the web interface to add and manage receive 450 MHz frequencies.
If you have a receiver with the transmit option, Trimble must specify and configure the (FCC-

approved) transmit broadcast frequencies at the factory. You cannot configure these yourself. If you
obtain extra Transmit frequencies once you have your receiver, contact your local Trimble authorized
dealer to have the extra frequencies added. The dea ler will provide you with a Set file, which you can
transfer to the receiver using the WinFlash utility.

Adding receive frequencies for the 450 MHz internal receive radio

1. Start the WinFlash utility. The Device Configuration screen appears.

2. From the Device type list, s elec t the requ ired rece iv er.

3. From the PC serial port field, select the serial (COM) port on the computer that the receiver is
connected to.

4. Click Next. The Operation Selection dialog appears. The Operations list shows al l of the
supported operations for the selected device. A description of the selected operation is shown in the
Description field.

5. Select Configure Radio Settings and then click Next. Either the Internal Transceiver
Configuration dialog or Frequency Selection dialog appears depending on the receiver:

Glossary

27

6.

7. In the Wireless Format group, select the appropriate channel and wireless mode. The Wireless
mode must be the same for all radios in your network.

8. In the Specify Frequency field, enter the frequency you want to add.

9. Click Add. The new frequency appears in the Selected Frequencies list.

Note - The programmed frequencies must conform to the channel spacing and minimum tuning
requirements for the radio. To view this information, click Radio Info. You can select 12.5 kHz or 25
kHz channel spacing. All radios in your network must use the same channel spacing.

10. Once you have configured all the frequencies that you require, click OK.

11. The WinFlash utility updates the receiver radio frequencies and then restarts the receiver.

SPS852 Getting Started Guide

28

Setting UHF reception radio frequencies using the web interface

To enter your own Receive (Rx) frequency using the web interface:

1. Select the Radio menu.

2. Select the Frequency Management submenu.

3. Make a note of the details shown in the Frequency range and Tuning step fields. Any new
frequencies must be within the range shown and must also be a multiple of the K Hz shown in
the Tuning step field.

4. Select the Add Channel option and then enter the new channel frequency.

5. Click OK.

To delete a channel frequency:

1. Select the Delete channel option.

2. Select a channel to delete from the list that appears.

You cannot add or delete Transmit channels using the web interface.

Glossary

29

Troubleshooting

This section describes some possible receiver issues, possible causes, and how to solve them. Please
read this section before you contact Technical Support.

Issue

Possible cause

Solution

The receiver does not
turn on

External power is too low.

Check the charge on the e xternal power supply, and

check the fuse if applicable. If required, replace the

battery.

Internal power is too low.

Check the charge on the internal batteries and replace if

required.
Ensure battery contacts are clean.

External power is not

properly connected.

Check that the Lemo connection is seated properly.

Check for broken or bent pins in the connector.

Faulty external power cable.

Try a different cable.

Check pinouts with multimeter to ensure internal

wiring is intact.

Receiver does not log

data

Insufficient memory in the

internal memory.

Delete old files using the GPS Configurator software,

or press for 30 seconds.

The receiver is tracking fewer

than four satellites.

Wait until the SV Tracking LED is flashing slowly.

Use the SCS900 software. Go to the SkyPlot

screen and

press Ctrl+M to access the current elevation mask
settings. Reduce the mask value to make more satellites
available.
The default mask setting for receiver is 10° above the
horizon. Change the value to a lower setting
temporarily while you are waiting for a b e tte r

constellation availability.

The data loggi

ng option is not

enabled.

Check the original purchase order or the receiver

configuration using the WinFlash utility. If da t a logging
is not enabled on the receiver, you can order the option
from your local Trimble Site Positioning Systems
dealer, and upgrade the receiver using the WinFlash

utility.

Receiver is not tracking

any satellites

GPS antenna does not have
clear line of sight to the sky.

Ensure that the antenna has a clear line of sight.

The cable between receiver

and the GPS ant enna is
damaged.

Replace the cable.

Cable connections at receiver

or antenna are not tightly
seated, or are connected
incorrectly.

Check all cable connections.

The receiver is not

responding

Receiver needs a soft reset.

Turn off the r eceiver and then turn it ba ck on again.

Receiver needs a full reset.

Press for 30 seconds.

The SPS Modular

receiver cannot be set
up as a base station
using the SCS900
software

The SPS Modular receiver
may have been purchased as a
rover receiver rather than with

the optional base station
capability.

Ask your local dealer to check the Optio n Bit settings,
else check the setting yourself using the WinFlash
utility. If required, upgrade the receiver.

SPS852 Getting Started Guide

30

Glossary

1PPS

Pulse-per-second. Used in hardware timing. A pulse is generated in conjunction with a time
stamp. This defines the instant when the time stamp is applicable.

almanac

A file that contains orbit information on all the satellites, clock corrections, and atmospheric
delay parameters. The alman ac is transmitted by a GPS satellite to a GPS receiver, where it

facilitates rapid acquisition of GPS signals when you start collecting data, or when you have lost

track of satellites and are trying to regain GPS signals.
The orbit information is a subset of the ephemeris/ephemerides data.

AutoBase

AutoBase technolo gy uses the position of the receiver t o automatically select the correct base
station; allowing for one button press operation of a base station. It shortens setup time
associated with repeated daily base station setups at the same location on jobsites.

base station

Also called reference sta tion. A base station in construction, is a receiver placed at a known
point on a jobsite that tracks the same satellites as an RTK rover, and provides a real-time

differential correction message stream through radio to the rover, to obtain centimeter level

positions on a continuous real-time basis. A base station can also be a part of a virt ual reference
station network, or a location at which GPS observations are collected over a peri od of time, for
subsequent postprocessing to obtain the most accurate position for the location.

beacon

Source of RTCM DGPS cor r ections transmitted from coast al reference stations in the 283.5 to

325.0 kHz range.

BINEX

BInary EXchange format. BINEX is an operational binary format standard for
GPS/GLONASS/SBAS research purposes. It is designed to grow and allow encapsulation of all
(or most) of the information currently allowed for in a range of other formats.

broadcast serve r

An Internet server that manages authentication and password control for a network of VRS
servers, and relays VRS corrections from the VRS server that you select.

carrier

A radio wave having at least one characteristic (such as frequency, amplitud e, o r phase) that can
be varied from a known reference value by modulation.

carrier frequency

The frequency of the unmodulated fundamental output of a radio transmitter. The GPS L1
carrier frequency is 1575.42 MHz.

carrier phase

Is the cumulative phase co unt of the GPS or GLONASS carrier si gnal at a given time.

cellular modems

A wireless adaptor that connects a laptop computer to a cellular pho ne system for data transfer.
Cellular modems, which contain their own antennas, plug into a PC Card slot or into the USB
port of the computer and ar e avai lable for a variety of wireless data services such as GPRS.

CMR/CMR+

Compact Measurement Record. A real-time message format develop ed by Trimble for
broadcasting corrections to other Trimble receivers. CMR is a more efficient al ternative to

RTCM.

CMRx

A real-time message format developed by Trimble for transmitti ng more satellite corrections
resulting from more satellite signals, more constellations, and more satellites. Its compactness
means more repeaters can be used on a site.

covariance

A statistical measure of th e variance of two random variables that are observed or measured in
the same mean time period. This measure is equal to th e product of the deviations of
corresponding valu es of the two variables from their r es pective means.

datum

Also called geodetic datum

. A mathematical model designed to best fit the geoid, defined by the

relationship between an ellipsoid and, a point on the topographic surface, established as the
origin of the datum. World geodetic datums are typically defined by the size and shape of an

ellipsoid and the relationship between the center of the ellipsoid and the center of the earth.

Because the earth is not a perfect ellipsoid, any single datum will provide a bett er model in
some location

s than in others. Therefore, various datums have been established to suit particular

regions.

Glossary

31

For example, maps in Europe are often based on the European datum of 1950 (ED-50) . Ma ps in

the United States are often based on the North American datum of 1927 (NAD-27) or 1983
(NAD-83).

All GPS coordinates are based on the WGS-84 datu m sur face.

deep dischar ge

Withdrawal of all electrical energy to the end-point voltage before the cell or bat tery is
recharged.

DGPS

See real-time differential GPS.

differential correction

Differential correcti on is the process of correcting GPS data collected on a rover with data
collected simultaneo usly at a base station. Because the base station is o n a known location, any
errors in data collected at the base station can be measured , and the necessary corrections
applied to the rove r data .

Differential correcti on can be done in real-time, or after the data is collected b y postprocessing.

differential GPS

See real-time differential GPS.

DOP

Dilution of Precision. A measure of the quality of GPS positions, based on the geometry of the
satellites used to compu te the positions. When satel lites are widely spaced relative t o each other,
the DOP value is lower, and position accuracy is greater. When satellites are close together in
the sky, the DOP is higher and GPS positions may contain a greater level of error.

PDOP (Position DOP) indicates the three-dimensional geometry of the satellites. Other DOP

values include HDOP (Horizontal DOP) and VDOP (Vertical DOP), which indicate the
accuracy of horizontal measur ements (latitude and longitude) and vertical measure ment s
respectively. PDOP is related to HDOP and VDOP as follo ws: PDOP² = HDOP² + VDOP².

dual-frequency GPS

A type of receiver that us es both L1 and L2 signals from GPS satellites. A dual-frequency
receiver can compute more precise position fixes over longer distances and u nder more adverse
conditions because it compensates for ionospheric delays.

EGNOS

European Geostationary Navigation Overlay Service. A satellite-based augment ation system
(SBAS) that provides a free-to-air differential correction service for GPS. EGNOS is the
European equivalent of WAAS, which is available in the United States.

elevation mask

The angle below which the receiver will not track satellites. Normally set to 10 degrees to avoid

interference problems caused by buildings and trees, atmospheric issues, and multipath errors.

ellipsoid

An ellipsoid is the three-dimensional shape that is used as the basi s fo r mathematically
modeling the earth’s surface. The ellipsoid is defined by the lengths of the minor and major
axes. The earth’s minor axis i s the polar axis and the major axis is the equatorial axis.

EHT

Height above ellipsoid.

ephemeris/ephemerides

A list of predicted (accurate) positions or locations of satellites as a function of time. A set of
numerical parameters th at can be used to determine a satellite’s position. Available as broadcast
ephemeris or as postpro ces sed precise ephemeris.

epoch

The measurement interval of a GPS receiver. The epoch varies according to the measurement
type: for real-time measurement it is set at one second; for postprocessed measurement it can b e
set to a rate of between one second and one minute. For exa mpl e, if data is measured every 15
seconds, loading data using 30-second epochs means loading every alternate measurement.

feature

A feature is a physical object or event that has a location in the real world, which you want to
collect position and/ or descriptive information (attributes) about. Feat ures can be classified as
surface or non-surface features, and again as points, lines/breaklines, or boundaries/areas.

firmware

The program inside the recei ver that controls recei ver operations and hardware.

Galileo

Galileo is a GNSS system built by the European Union and the European Space Agency. It is
complimentary to PPS and GLONASS.

GHT

Height above geoid.

SPS852 Getting Started Guide

32

GIOVE

Galileo In-Orbit Validation Element. Th e name of each satellite for the European Space Agency
to test the Galileo positioning system.

GLONASS

Global Orbiting Navigation Satellite System. GLONASS is a Soviet space-based navigation
system comparable to the American GPS system. The operational system consists of 21
operational and 3 non-operational satellites in 3 orbit planes.

GNSS

Global Navigation Satellite System.

GSOF

General Serial Output Format. A Trimble proprietary message format.

HDOP

Horizontal Dilution of Precision. HDOP is a DOP value that indicates th e accuracy of horizontal
measurements. Other D OP values include VDOP (vertical DO P) and PDOP (Position DOP).

Using a maximum HDOP is ideal for situations where vertical precision is not particularly
important, and your position yield would be decreased by the vertical component of the PDOP
(for example, if you are col lecting data under canopy).

IBSS

Internet Base Station Service. This Trimble service makes t he setup of an Internet-capable SPS
receiver as simple as poss ible. The base station can be connected to the Internet (cab le or
wirelessly). To access the distribution server, the user enter a password in to the receiver. To use
the server, the user must h ave a T rimble Connected Co mmunity site license.

L1

The primary L-band carrier used by GPS and GLONASS satellites to transmit satellite data.

L2

The secondary L-band carrier used by GPS and GLONASS satellites to transmit satellite data.

L2C

A modernized code that al lows significantly better ability to track the L2 frequency.

L5

The third L-band carrier used by GPS satellites to transmit satellite data. L5 will provide a
higher power level than the other carriers. As a result, acquiring and tracking weak signal s will
be easier.

Location RTK

Some applications such as vehicular-mounted site supervisor systems do not require Precision
RTK accuracy. Location RTK is a mode in which, once initialized, the receiver will operate
either in 10 cm horizontal and 10 cm vertical accuracy, or in 10 cm horizontal and and 2 cm
vertical accuracy.

Mountpoint

Every single NTripSource needs a unique mountpoint on an NTripCaster. Before transmitting
GNSS data to the NTripCaster, the NTripServer sends an assignment of the mountpoint.

Moving Base

Moving Base is an RTK positioning technique in which both reference and rover receivers ar e
mobile. Corrections are sent from a “base” receiver to a “r over” receiver and the resultant
baseline (vector) has centimeter-level accuracy.

MSAS

MTSAT Satellite-Based Augmentation System. A satellite-based augmentation system (SBAS)
that provides a free-to-air di fferential correction service for GPS. MSAS is the Japanese
equivalent of WAAS, which is availabl e in the United States.

Multipath

Interference, similar to ghosts on an analog televisi on screen, that occurs when GPS signals
arrive at an antenna havi ng tra

versed different paths. The signal traversing the longer path yields

a larger pseudorange estimate and increases the error . Multiple paths can arise from re flect ions
off the ground or off structures near the antenna.

NMEA

National Marine Electr onics Association. NMEA 0183 defines the standard for interfacing
marine electronic navigat ional devices. This standard defines a number of 'strings' referred to as
NMEA strings that contain navigational details such as positions. Most Trimble GPS receivers
can output positions as NMEA strings.

NTrip Protocol

Networked Transport of RTCM via Internet Protocol (NTrip) is an application-level protocol
that supports streaming Global Navigation Satellite System (GNSS) data over the Internet.
NTrip is a generic, stateless protocol based on the Hypertext Transfer Protocol (HTTP). The
HTTP objects are extended to GNSS data streams.

NTripCaster

The NTripCaster is basically an HTTP server suppor ting a subset of HTTP request /response

Glossary

33

messages and adjusted to low-bandwidth streaming data. The NTripCaster accepts request

messages on a single port from either the NTripServer or the NTripClient. Depending on these
messages, the NTripCaster decides whether there i s s treaming data to receive or t o send.

Trimble NTripCaster integrates the NTripServer and the NTripCaster. This port is used only to
accept requests from NTripClients.

NTripClient

An NTripClient will be accepted by and receive data from an NTripCaster, if the NTripClient
sends the correct requ es t message (TCP/UDP connect io n to the specified NTripCaster IP and
listening port).

NTripServer

The NTripServer is used to transfer GNSS data of an NTripSource to the NTripCaster. An
NTripServer in its simplest setup is a computer program running on a PC that sends correction
data of an NTripSource (for example, as received through the serial communication port from a
GNSS receiver) to the NTripCaster.

The NTripServer - NTripCaster communication extends HTTP by additional message formats
and status codes.

NTripSource

The NTripSources provide continuous GNSS data (for example, RTCM-104 corrections) as
streaming data. A single source represents GNSS data referring to a specific location. Source
description parameters are compiled in the source-table.

OmniSTAR

The OmniSTAR HP/XP service allows the use of new generation dual-frequency receivers with
the OmniSTAR service. The HP/XP service does not rely on local reference stations fo r its
signal, but utilizes a global satellite monitoring network. Additionally, while most current dual­frequency GPS systems are accurate to within a meter or so, OmniSTAR with XP is accurate in
3D to better than 30 cm.

PDOP

Position Dilution of Precision. PDOP is a DOP value t hat indicates the accuracy of thr ee­dimensional measurements. Other DOP values include VDOP ( vertical DOP) and HDOP
(Horizontal Dilution of Precision).

Using a maximum PDOP value is ideal for situations where both vertical and horizontal
precision are important.

POE

Power Over Ethernet. Provides DC power to the SPS Mod ul ar GPS receiver using an Ethernet
cable.

postprocessing

Postprocessing is the processing of satellite data after it is collected, in order to eliminate error.
This involves using computer software to compare data from the rover with data collected at the
base station.

real-time differential
GPS

Also known as real-time differential correction or DGPS. Real-time differential GPS is the
process of correcting GP S data as you collect it. Correct ions are calculated at a base station and
then sent to the receiver through a radio link. As the rover receives the position it applies the
corrections to give you a very accurate position in the field.

Most real-time differential correction methods apply corrections to code phase positions.
While DGPS is a generic term, its common interpretation is that it entails the use of single-

frequency code phase data sent from a GPS base statio n to a rover GPS receiver to provide sub­meter position accuracy. Th e r over receiver can be at a l ong range (greater than 100 kms (62
miles)) from the base station.

Rover

A rover is any mobile GPS receiver that is used to collect or update data in the field, typically at

an unknown location.

Roving mode

Roving mode applies to the use of a rover receiver to collect data, stakeo ut, or control
earthmoving machinery in r eal time using RTK techniques.

RTCM

Radio Technical Commission for Maritime Services. A commission established to define a
differential data link for the real -time differential correctio n of roving GPS receivers. There are
three versions of RTCM cor r ection messages. All Trimble GPS receivers use Version 2 protocol
for single-frequency DGPS type corrections. Carrier phase corr ections are available on Version
2, or on the newer Version 3 RTCM protocol, which is available on certain Trimble dual­frequency receivers. The Version 3 RTCM protocol is more compact but is not as widely
supported as Version 2.

SPS852 Getting Started Guide

34

RTK

real-time kinematic. A real-time differential GPS method tha t us e s carrier phase measurements
for greater accuracy.

SBAS

Satellite-Based Augmentation System. SBAS is based on differential GPS, but applies to wide
area (WAAS/EGNOS/MSAS) networks of reference stations. Corrections and additional
information are broadcast via geostationary satellites.

signal-to-nois e r atio

SNR. The signal strength of a satellite is a measure of the information content of the signal,
relative to the signal’s noise. The typical SNR of a satellite at 30° elevation is between 47 and
50 dBHz.

Skyplot

The satellite skyplot confirms reception of a differentially corrected GPS signal and displays the

number of satellites tracked by the GPS receiver, as well as their relative positions.

SNR

See signal-to-noise ratio.

Source-table

The NTripCaster maintains a source-table containing information on available NTripSources,
networks of NTripSources, and NTripCasters, to be sent to an NTripClient on request. Source­table records are dedicat ed to one of the following:

data STReams (record type STR)
CASters (record type CAS)
NETworks of data streams (record type NET)

All NTripClients must be able to decode record type STR. Decoding types CAS and NET is an

optional feature. All data fields in the source-table records are separated using the semicolon
character.

triple frequency GPS

A type of receiver that us es three carrier phase measurement s (L1, L2, and L5).

UTC

Universal Time Coord in ated. A time standard based on local solar mean time at the Greenwich
meridian.

VRS

Virtual Reference Station. A VRS system consists o f GPS hardware, software, and
communication links. It uses data from a network of base stations

to provide corrections to each

rover that are more accurate than corrections from a singl e base station.
To start using VRS corrections, the rover sends its position to the VRS server. The VRS server

uses the base station data to model systematic errors (such as ionospheric noi se) at the rover
position. It then sends RTCM correction messages back to the rover.

WAAS

Wide Area Augmentation System. WAAS was established by the Federal Aviation

Administration (FAA) for flight and approach navigation for civil aviation. WAAS improves the

accuracy and availability of the basic GPS sign als over its coverage area, which includes the
continental United St ates and outlying parts of Canada and Mexico.

The WAAS system provides correction data for visible satellites. Corrections are computed

from ground station observations and then uploaded to two geostationary satellites. This data is

then broadcast on the L1 frequency, and is tracked using a channel on the GPS receiver, exactly
like a GPS satellite.

Use WAAS when other correction sources are unavailable, to obtain greater accur acy than
autonomous positions. For more information on WAAS, refer to the FAA website at

http://gps.faa.gov.

The EGNOS service is the European equivalent and MSAS is the Japanese equivalent of
WAAS.

WGS-84

World Geodetic System 1984. Since January 1987, WGS-84 has superseded WGS-72 as the

datum used by GPS.

The WGS-84 datum is based on the ellipsoid of the same name.

35

Legal Notices

Corporate Office

Trimble Navigation Limited
935 Stewart Drive
Sunnyvale, CA 94085
USA

www.trimble.com

Heavy Highway business area

Trimble Navigation Limited
Heavy Highway business area
5475 Kellenburger Road
Dayton, Ohio 45424-1099
USA

800-538-7800 (toll free in USA)
[phone] Phone
[phone] Fax

www.trimble.com

E-mail: [e-mail]

Legal Notices

© 2006–2010, Trimble Navigation Limited. All rights reserved.
Trimble, the Globe & Triangle logo, and TSC2 are trademarks of Trimble Navigation Limited, registered in the United

States and in other countries. AutoBase, CMR, CM R+, EVEREST, HYDROpro, Maxwell, Micro-Centered, Trimble
Geomatics Office, SiteNet, TRIMMARK, TRIMTALK, TSCe, VRS, Zephyr, and Zephyr Geodetic are trademarks of
Trimble Navigation Limited.

The Bluetooth word mark and logos are owned by the Bluetooth SIG, Inc. and any use of such marks by Trimble
Navigation Limited is under license. Microsoft, Windows, and Windows NT are either registered trademarks or
trademarks of Microsoft Corporation in the United States and/or other countries.All other trademarks are the property of
their respective owners.

NTP Software Copyright
© David L. Mills 1992-2009. Permission to use, copy, modify, and distribute this software and its documentation for any
purpose with or without fee is hereby granted, provided that the above copyright notice appears in all copies and that
both the copyright notice and this permission notice appear in supporting documentation, and that the name University of
Delaware not be used in advertising or publicity pertaining to distribution of the software without specific, written prior
permission. The University of Delaware makes no representations about the suitability this software for any purpose. It is
provided "as is" without express or implied warranty.

Release Notice

This is the April 2010 release (Revision A) of the SPS Receivers Help. It applies to version 4.15 of the receiver
firmware.

Product Limited Warranty Information

For applicable product Limited Warranty information, please refer to the Limited Warranty Card included with this
Trimble product, or consult your local Trimble authorized dealer.

COCOM limits

The U.S. Department of Commerce requires that all expo rtable GPS products con tain performance limitations so that
they cannot be used in a manner that could threaten the security of the United States. The following limitations are
implemented on this product:

SPS852 Getting Started Guide

36

Immediate access to satellite measurements and navigation results is disabled when the receiver velocity
is computed to be greater than 1,000 knots, or its altitude is computed to be above 18,000 meters. The
receiver GPS subsystem resets until the COCOM situation clears. As a result, all logging and stream
configurations stop until the GPS subsystem is cleared.

Notices

Class B Statement – Notice to Users. This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC rules and Part 90. These limits are designed to provide reasonable
protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to
radio communication. However, there is no guarant ee that interference will no t occur in a particular installation. If this
equipment does cause harmful interference to radio or television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

Reorient or relocate the receiving antenna.
Increase the separation between the equipment and the receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
Changes and modificati ons not expressly approved by the ma nufacturer or registrant of this equipment can vo i d
your authority to operate this equipment under Federal Communications Commission rules.

Canada

This Class B digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.
This apparatus complies with Canadian RSS-GEN, RSS-310, RSS-210, and RSS-119.
Cet appareil est confo r me à la n orme CNR-GEN, CNR-310, CNR-210, et CNR-119 du Canada.

Europe

The product covered by th is guide are intended to be used in all EU member countries, Norway, and Switzerland.
Products been tested and found to comply with the requirements for a Class B device pursuant to European Council
Directive 89/336/EEC on EMC, thereby satisfying the requirements for CE Marking and sale within the European
Economic Area (EEA). Contains a Bluetooth radio module. These requirements are designed to provide reasonable
protection against harmful interference when the equipment is operated in a residential or commercial environment. The
450 MHZ (PMR) bands and 2.4 GHz are non-harmonized through out E urope.

CE Declaration of Conformity

Hereby, Trimble Navigation, declares that the GPS recei vers ar e in compliance with t he essential requirements and other
relevant provisions of Directive 1999/5/EC.

Australia and New Zealand

This product conforms with the regulatory requirements of the Australian Communications and Media Authority
(ACMA) EMC framework, thus satisfying the requirements for C-Tick Marking and sale within Australia and New
Zealand.

Taiwan – Battery Recycling Requirements

(SPSx51 and SPS882 only)

Legal Notices

37

The product contains a removable Lithium-ion battery. Taiwanese regulations requir e that waste batteries are recycled.

廢電池請回收

Restriction of Use of Certain Hazardous Substances in Electrical and Electronic Equipment
(RoHS)

Trimble products in this guide comply in all material respects with DIRECTIVE 2002/95/EC OF THE EUROPEAN
PARLIAMENT AND OF THE COUNCIL of 27 January 2003 on the restriction of the use of certain hazardous
substances in electrical and electronic equipment (RoHS Directive) and Amendment 2005/618/EC filed under C(2005)
3143, with exemptions for lead in solder pursuant to Paragraph 7 of the Annex to the RoHS Directive applied.

Waste Electrical and Electronic Equipment (WEEE)

For product recycling instructions and more information, please go to www.trimble.com/ev.shtml.

Recycling in Europe: To recycle Trimble WEEE (Waste Electrical and Electron ic Equipment, products that run on
electrical power.), Call [phone], and ask for the “WEEE Associate”. Or, mail a request for recycling
instructions to:
Trimble Europe BV
c/o Menlo Worldwide Logistics
Meerheide 45
5521 DZ Eersel, NL

FCC Declaration of Conformity

We, Trimble Navigation Limited.

935 Stewart Drive

PO Box 3642

Sunnyvale, CA 94088-3642

United States

[phone]

Declare under sole responsibility that DoC products comply wi

th Part

15 of FCC Rules.

Operation is subject to the following two conditions:

(1) This device may not cau s e harmful interference, and

(2) This device must accept any interference received, i ncluding

interference that may cause undesired operation

Unlicensed radios in products

This device complies with part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) This device may not cau s e harmful interference, and

(2) This device must accept any interference received, i ncluding interference that may cause undesired operation.

Licensed radios in products

This device complies with part 15 of the FCC Rules.
Operation is subject to the condition that this device may no t cause harmful interference.