Exploranium GR-135 User guide

GR-135
THE IDENTIFIER
SYSTEM MANUAL
Part #87317-1 Rev.3.4
July 2004

SAIC Exploranium – GR-135 System Manual page: 2
GR-135
THE IDENTIFIER
SYSTEM MANUAL
Table of Contents
1.0 GENERAL SYSTEM DESCRIPTION:....................................................................................6
1.1 GR-135 HARDWARE VERSIONS ....................................................................................6
1.2 GR-135 OPERATIONAL MODES.....................................................................................6
1.3 SOFTWARE RELEASES .................................................................................................6
2.0 SYSTEM DESCRIPTION & FEATURES.................................................................................7
2.1 OPERATIONAL FUNCTIONS..........................................................................................7
2.2 SYSTEM FEATURES......................................................................................................7
3.0 JOYSTICK OPERATION ................................................................................................... 11
4.0 QUICK START – MANUAL MODE..................................................................................... 12
5.0 DETAILED OPERATION GUIDE ....................................................................................... 13
5.1 JOYSTICK..................................................................................................................13
5.2 POWER .....................................................................................................................13
5.3 SWITCHING FROM AUTOMATIC MODE TO MANUAL MODE..........................................15
5.4 DISPLAY CONTRAST ..................................................................................................16
5.5 MAIN MENU ..............................................................................................................16
5.6 STABILIZATION.........................................................................................................17
5.7 EXTERNAL AUDIO......................................................................................................17
6.0 SEARCH+DOSE ...............................................................................................................18
6.1 SEARCH MODE ..........................................................................................................18
6.2 HIGH DOSE...............................................................................................................18
6.3 NEUTRON ALARM ......................................................................................................19
6.4 SEARCH ALARM.........................................................................................................19
6.5 SEARCH - AUDIO.......................................................................................................19
6.6 SEARCH MODE - DATA RECORDING ...........................................................................19
7.0 IDENTIFY........................................................................................................................ 21
7.1 IDENTIFY DISPLAY ....................................................................................................21
7.2 ANALYSIS MENU........................................................................................................22
7.3 STORE SPECTRUM.....................................................................................................22
7.4 START MEAS .............................................................................................................22
7.4.1 DATA OVERFLOW ..........................................................................................23
7.5 SEE SPECTRUM .........................................................................................................23
7.5.1 SEE SPECTRUM...............................................................................................23
7.6 PEAK ANALYSIS.........................................................................................................24
7.7 NUCLIDE IDENT ........................................................................................................25

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7.7.1 NUCLIDE DETAILS............................................................................................25
7.7.2 NEUTRONS.....................................................................................................26
7.7.3 OTHER DISPLAY LABELS .................................................................................26
8.0 STABILIZE....................................................................................................................... 27
8.1 STABILIZATION - GENERAL........................................................................................27
8.2 AUTO-STABILIZATION IN THE DOCKING STATION – AUTOMATIC MODE .....................27
8.3 MANUAL-STABILIZATION IN THE DOCKING STATION .................................................27
8.4 AUTOMATIC CORRECTION WHEN IN USE...................................................................28
9.0 DATA MEMORY ...............................................................................................................29
9.1 STATUS.....................................................................................................................29
9.1.1 MEMORY SPACE..............................................................................................29
9.2 DUMP........................................................................................................................30
9.3 ERASE.......................................................................................................................30
9.4 MEM SCAN ................................................................................................................30
10.0 SETUP ........................................................................................................................... 32
10.1 SEARCH ....................................................................................................................32
10.2 STABILIZE.................................................................................................................34
10.3 IDENTIFY..................................................................................................................35
10.3.1 DETECTOR.....................................................................................................35
10.3.2 NaI................................................................................................................36
10.3.3 CZT ...............................................................................................................38
10.3.4 NEUTRON ......................................................................................................38
10.4 DOSE........................................................................................................................39
10.5 DATE/TIME ...............................................................................................................40
10.6 ROIS.........................................................................................................................40
10.7 MISCELLANEOUS.......................................................................................................40
11.0 MAINTENANCE ............................................................................................................. 42
11.1 MAINTENANCE MENU ................................................................................................42
11.2 LIBRARY ...................................................................................................................42
11.3 CHARGING................................................................................................................42
11.4 REMOTE....................................................................................................................42
11.5 DEFAULTS.................................................................................................................43
11.5 ADC TEST .................................................................................................................43
12.0 SPECIFICATIONS.......................................................................................................... 44
APPENDIX A - AUTOMATIC MODE OPERATION .................................................................... 48
APPENDIX B - IDENTIVIEW SOFTWARE ............................................................................... 57
APPENDIX C - OPERATION WITHOUT THE DOCKING-STATION........................................... 69
APPENDIX D - NUCLIDE LIBRARIES ..................................................................................... 71
APPENDIX F - DOCKING STATION DETAILS ......................................................................... 71
APPENDIX G – RECOMMENDED PARAMETERS...................................................................... 73
APPENDIX H – WIPE TEST (OPTIONAL)................................................................................ 74

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APPENDIX J – SENSOR LOCATIONS....................................................................................... 76
APPENDIX X – WARRANTY..................................................................................................... 77
APPENDIX Z - DOCKING-STATION TEST SOURCE SPECS ...................................................... 79

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GR-135 – THE IDENTIFIER

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GR-135
THE IDENTIFIER
SYSTEM MANUAL
1.0 GENERAL SYSTEM DESCRIPTION:
The GR-135 - THE IDENTIFIER - represents a major breakthrough in the field of
radiation monitoring, offering the user not only the ability to search for and locate radioactive
material but also to automatically identify the radioactive nuclides present. This capability in a
fully portable hand-held unit will permit its use in a wide variety of applications including :
- Hazard identification and risk assessment
- Inspection of incoming and outgoing material for radioactive contamination
- Inspection of radioactive gauges for leaks
- SEARCH of waste sites for radioactive material
- Employee exposure rate and dose monitoring
- Radioactive source monitoring
- Government inspection for material compliance
- Identification of unknown radioactive material
- Regulatory control of radioactive material
- Classification of radioactive material for a wide variety of users
1.1 GR-135 HARDWARE VERSIONS
a) GR-135 – the basic GR-135 model is a 2-detector system – utilizing a Sodium-Iodide detector
for high sensitivity and a G-M detector for extended Dose Rate range. This model replaces the
older GR-130 model
b) GR-135N – a 3-detector system – in addition to the Sodium-Iodide detector and G-M
detector there is an additional NEUTRON detector
c) GR-135CN – a 4 detector system - in addition to the Sodium-Iodide, G-M and NEUTRON
detectors this model incorporates an additional CZT detector for special applications.
d) DOCKING STATION – all of these models can be supplied with a Docking Station, which
permits operation in a special AUTOMATIC mode highly suitable for semi-technical users
(Appendix A).
1.2 GR-135 OPERATIONAL MODES
The GR-135 can be operated in 2 different modes.
a) AUTOMATIC MODE – restricted to SEARCH and IDENTIFY functions only. All other functions
are disabled to simplify system use by non-technical personnel – available only to DOCKING-
STATION users
b) MANUAL MODE – unrestricted system operation
Selection between modes is via a special switch in the battery compartment to restrict
unauthorized adjustments.
1.3 SOFTWARE RELEASES
This manual describes the current software release as defined in the title, all information
regarding system software or hardware changes and improvements are detailed in Appendix Y.

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2.0 SYSTEM DESCRIPTION & FEATURES
This manual fully describes the MANUAL mode so full system functionality is covered
See Appendix A for AUTOMATIC mode operation
2.1 OPERATIONAL FUNCTIONS
The GR-135 may be operated in 2 Primary radiation monitoring functions.
a) SEARCH + DOSE mode
In this mode, the GR-135 acts as SEARCH Meter displaying the current COUNT RATE in
counts/sec. A variable-tone AUDIO will indicate radiation intensity with an automatic audio meter
or user adjusted alarm level. A “chart-record” of the last 100 data points is displayed on the
screen during the SEARCH. This mode is typically used to search for radioactive material or to
carry out Total-Count grid Search.
This mode also displays the current DOSE RATE (in selectable units and quantities) as well as
ACCUMULATED DOSE from the time the mode was enabled. The dose meter is used to
determine the relative hazard level and to assess handling requirements of a radioactive material.
Dose Search of an area can also be carried out in this mode
b) IDENTIFY mode – (Nuclide Identification)
In this mode, the GR-135 accumulates spectral data from a sample and analyses the spectrum in
terms of emitted energy level and net count contribution. The nuclides responsible for producing
the spectrum are identified by comparison to a nuclide library and presented in tabular form.
This essential information can then be used to determine risk assessment. If the optional CZT
detector is used the unit automatically decides on detector use as determined by the source
signature, so this is fully automatic.
2.2 SYSTEM FEATURES
a) INSTRUMENT BODY - The instrument body consists of 2 primary parts, the lower case and top
panel. The lower case is deep-formed aluminum that provides a strong basic structure. The top
panel is specially formed ABS plastic that minimizes weight while maintaining the ruggedness of
the unit. The combination of the two parts provides a high degree of system strength, suitable
for field operations where mechanical abuse may be unavoidable.
b) DETECTOR –
1- NaI - The 4.0 cu. in. (0.065L) Sodium-Iodide [NaI (Tl)] detector assembly is specially
designed for rugged environments. The NaI crystal is enclosed in a specially molded
rubber sleeve to give a high degree of mechanical protection against shock and is fully
enclosed within the instrument body.
2 - GM – the rugged GM tube is mounted just behind the instrument front face and is used
to extend the Dose Rate range to 1R+ for special applications
3 - NEUTRON – this detector is a solid-state non-gaseous detector with high sensitivity and
has no travel restrictions.
4 - CZT - this optional detector is used in special applications to improve the systems Nuclide
ID capability. CZT is a specialized detector with a resolution approx twice that of Sodium-
Iodide thus allowing discrimination of some peaks that are impossible to see on a NaI
detector.
c) HANDLE - The handle is a custom designed molded rubber part with a carefully designed
diameter and special indentations for fingers. The rubber type was selected to give a good
balance between strength and comfort.

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d) JOYSTICK - The GR-135 has only one operating control - the rubber-covered joystick on the
handle. All system functions are controlled by the JOYSTICK that permits very easy instrument
functions EVEN WHEN WEARING GLOVES IN A BIOHAZARD SUIT. The JOYSTICK is a
specially designed switch with five actions – UP, DOWN, LEFT, and RIGHT. The JOYSTICK and
use of menu driven functions makes the GR-135 very easy to operate and avoids the necessity of
“memorizing” complex sequences of action.
OPTIONAL: for AUTOMATIC mode users only – a handle with a single PUSH-BUTTON switch is
available to make user actions as simple as absolutely possible.
e) DISPLAY - An LCD is used for the GR-135 to permit a full range of alphanumeric and graphic
display capabilities. This LCD gives excellent contrast in high light conditions but is not easily
visible in low light conditions.
To solve this problem, the system has a “BACKLITE” function, which provides excellent visibility
in a low light environment. The display contrast may also be manually adjusted depending on
ambient light conditions. The unit also incorporates automatic temperature compensation to
maintain correct contrast even when the temperature substantially changes.
f) BACK-DOOR - The GR-135 has a back door that is removable by a ¼ turn of the integrated
handle. The door may be removed to allow access to the battery compartment to change
batteries and the I/O connectors as required. These connectors are for use when the supplied
Docking-Station is inconvenient. The door is gasketed to provide a high degree of water
protection when in place.
Rear View with Battery Door Removed
COM - RS-232 Communication Connector
AUTOMATIC/MANUAL SWITCH
12 - VDC – Battery Charging Connector
EARPHONEJACK
g) BATTERIES - The GR-135 requires two D-cell batteries. Three types of batteries can be used.
Standard Nickel-Cadmium rechargeable batteries provide 8 hours of normal operation when fully
charged. Nickel-Metal Hydride rechargeable batteries provide 12 hours of operation when fully charged.
Alkaline batteries may also be used. They provide 12 hours of normal operation.

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WARNING: Users are reminded not to place the GR-135 in the Docking Station, or connect
any battery charger to the unit while alkaline batteries are being used, as this will result in
battery leakage and extensive system damage.
While rechargeable batteries are shipped fully charged, they will self-discharge with time when not in
use. It is important to condition new batteries, whether received with the system or purchased
separately. Conditioning is achieved by first totally discharging the batteries in the GR-135 unit outside
the docking station and then fully charging them in the docking station for at least 12 hours.
NOTE: To get reliable performance and full capacity out of the batteries throughout their life, it is
important to let them fully discharge and then fully re-charge for 12 hours at least once every two
months. This will assure that the batteries provide 8 (12) hours of operation.
WARNING: Leaving the GR-135 in the docking station with the backlight activated over a long period of
inactivity may cause the batteries to be totally discharged. It is recommended to turn the backlight off if
the unit is not expected to be used within 4 hours. Alternately, it is advisable to lift the GR-135 from the
docking station and put it back at least once a day. This restores the charging cycle during the
prolonged period of inactivity.
h) BATTERY-CHARGER – in the GR-135 the battery charger is INTERNAL. This feature has been
added as this permits the battery charging system to be fully under software control. With the
increased availability of specialty batteries, this feature means that a wide variety of battery types
can be used in the instrument – the user simply selects battery type and the charger automatically
selects the correct charging parameters for this battery type.
i) DOCKING STATION (DS) – a Docking-Station is normally supplied with the GR-135. This
device is a cradle that the GR-135 unit sits in. The cradle is connected to the AC connection, has
an internal radioactive source (exempt quantity) and may be connected to a PC. 4 “fingers”
on the base of the GR-135 connect to mating 4 fingers on the Docking Station to provide
charging and data connections without opening the rear access data door.
The DOCKING STATION system comprises:
- the DS chassis - a special base that the GR-135 is seated in
- the system Test Source mechanically embedded in the DS
- an AC adaptor
- an RS-232 signal cable
Note that a stick on label (see fig) is on the DS
unit that specifies the fact that the internal test
source requires no licensing and no transport
restrictions apply. See the last page in this
manual for specific details of the applicable
documents to source possession and
transportation.
NON-DS OPERATION - Most users find that the Docking Station internal source makes it easier
to control sources, as small system test sources are easy to lose. For users who find the
Docking-Station operation unsuitable to their application – please advise Exploranium as a special
NON-DS KIT is available as an option that provides special cabling for charging/data I/O and a
test source to permit NON DS operation (see Appendix C)
This unit includes a very low activity radioactive
source. This source has NO license limitations
and NO shipping limitations apply as it is
considered an EXCEPTED PACKAGE as specified in
US NRC 49CFR 173.424 for radioactive material,
excepted package-instruments or articles,
UN2910.

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k) SYSTEM SUPPORT SOFTWARE - Support software named IdentiView is provided with the GR-
135 on a CD-ROM. This is a Windows based program and operates under Windows 95, 98, NT and
2000. The program is described in Appendix B and provides data downloading, data display,
custom library uploading, spectrum display analysis and various other features - as well as ASCII
downloading to produce the data in a format suitable for importing into various Spreadsheet
programs.
l) BOOT - A yellow “boot” is provided with the unit. This boot is custom molded from a
compressive material and, once installed, provides a high level of protection from accidental
mechanical damage. With the boot in place, the unit’s basic rugged design is further improved,
enabling the unit to withstand accidental drops or “knocks” against hard material. The boot also
provides an advantage when the unit is placed on wet or muddy ground by keeping the unit
clean and free from dirt. Note that this boot adds slightly to the system weight and is easily
removed if required, however Exploranium recommends using the unit with the boot in place
whenever possible.
m) VINYL CARRYING CASE - The system is supplied with a soft vinyl carrying case with shoulder
strap for easy transportation of the GR-135. An easy-open zipper flap allows access to the
instrument while providing additional weather protection. The carry-case also has an external
pocket for carrying notebooks, etc.
n) MANUAL - This user manual is supplied with the instrument. A special manual titled USER
MANUAL (AUTOMATIC mode), which covers only the limited AUTOMATIC mode operation
fully described in Appendix A, is available as required.
o) SHIPPING/STORAGE CASE - The GR-135 system is shipped to the customer in a rugged black
polyurethane carrying case that is fully waterproof and highly shock resistant. This case is
intended for shipping and/or storage purposes. It is equipped with a pressure purge valve and is
capable of withstanding air-cargo shipping abuse while offering a high level of protection to the
instrument. On site, most users carry the GR-135 in the vinyl carry-case leaving the storage case
back at the office. However, if the unit is to be transported under conditions where it could be
bumped or dropped, the shipping case is recommended and would prevent other luggage from
damaging the instrument.
NOTE : Even if the user does not intend to use the polyurethane storage case, it should be
kept in storage as Exploranium will only honor the full instrument warranty if the GR-
135 is returned in this (or a similar) case.

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3.0 JOYSTICK OPERATION
The unit is supplied with a single-button control device called THE JOYSTICK.
UP
(away
from you)
LEFT
RIGHT
JOYSTICK ACTIONS
DOWN
(towards you)

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4.0 QUICK START – MANUAL MODE
This section offers a VERY simplified guide to system operation; a more complete description is
available in Section 4+. The manual assumes that unit is being operated with the supplied
DOCKING-STATION (DS) – non-DS users please refer to Appendix C
a) CONNECT DOCKING STATION – connect the DS to an AC source using the cable supplied
b) REMOVE THE GR-135 BOOT – remove the attached Yellow protection boot
b) LOAD BATTERIES - remove rear door and insert 2 batteries – check polarity as marked - ONLY use
the supplied rechargeable batteries. Replace battery clamp and door and ensure the door is correctly
seated.
c) JOYSTICK OPERATION - the JOYSTICK mounted on the handle (see picture above) is the only
control on the instrument. Basic JOYSTICK actions are UP, DOWN, LEFT, RIGHT. Some
operations require a short activation SHORT = less than 0.5secs – or LONG = more then 1
second. ENTER in the manual means LONG DOWN (more than 1 second) – see graphic in
Section 3 above
d) POWER ON - a CLICK DOWN for at least 2 seconds - the unit will power ON and after a few
seconds the MAIN MENU is shown.
e) DOCKING-STATION – place the unit in the DS to charge the batteries
f) STABILIZE – while in the DOCKING-STATION (which has an embedded 0.25uCi Cs137 stabilization
source) select STABILIZE then ENTER (LONG DOWN) and follow display prompts to automatically
set the system gain
e) REMOVE from the DS and attach the Yellow boot for unit mechanical protection
f) SEARCH + DOSE - from the Main Menu, activate the SEARCH+DOSE mode by highlighting the
item in the Main Menu and using ENTER (LONG DOWN) to select. The system display will show
the current count rate in counts/sec while the internal “audio meter” will give an audio response with
the tone related to radiation intensity. DOSE RATE data is also displayed
g) STOP – to stop any function – press ENTER until you see STOP on the display. Then ENTER again
to go back to the Main Menu
h) IDENTIFY - Selecting IDENTIFY from the Main Menu begins a spectral reading for a pre-set
duration. At the end of the sample period, a menu permits viewing the spectrum, peak analysis,
Nuclide Identification, storing the spectrum for later analysis or output of the spectrum to a PC.
i) For a detailed explanation of these functions and other system functions - see the following Sections

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5.0 DETAILED OPERATION GUIDE
This section offers a detailed guide to system operation. The “AUTOMATIC” (= simplified) mode of
operation is described in Appendix A, note there is a special Users manual for “AUTOMATIC” only
operations.
The manual assumes that unit is being operated with the supplied DOCKING-STATION (DS) – non
DS users please refer to Appendix C for differences
5.1 JOYSTICK
The GR-135 is equipped with a rubber-covered
JOYSTICK on the instrument handle, referred to in
this manual as the JOYSTICK and this is the ONLY
control on the instrument. The great advantage of
this single button control is that besides being very
easy to use it also permits full operation EVEN
WHEN WEARING GLOVES – a definite advantage in
many applications where protective clothing is
required. Various Joystick actions are permitted
depending on the application:
CLICK UP/DOWN - a SHORT (up to 0.5 sec)
push (CLICK) of the JOYSTICK UP (away
from the user) or DOWN (towards the
user) is used to scroll through the system
menus
ENTER - holding the JOYSTICK DOWN (toward the ON position on the joystick label) for about
ONE SECOND (in the manual referred to as ENTER) is used to activate the selection
highlighted on the display
CLICK LEFT/RIGHT – SHORT click used in some menus to change parameters and in the Main
Menu to adjust display contrast.
5.2 POWER
a) BATTERIES
The GR-135 has an integrated Battery-Charging capability and operates with the supplied two D-cell
rechargeable NiCd batteries for Docking-Station usage. The internal battery charger permits the
battery charging system to be fully under software control. With the increased availability of
specialty batteries, this feature means that a wide variety of battery types can be used in the
instrument – the user simply selects battery type and the charger automatically selects the correct
charging parameters for this battery type. Consult Exploranium if special battery usage is required.
Alkaline batteries can be used but in this case DS operation is NOT permitted or system
damage and battery leakage may occur. An internal temperature sensor in the unit will shut power
down if an increased temperature is detected, to provide a high level of system protection but
system damage from battery leakage could still occur. See Appendix C for NON-DS operation.
When not in use for an extended period of time (1 month or more) – either leave
the unit charging in the DS – or remove the batteries to prevent leakage.
UP
(away
from you)
LEFT
RIGHT
JOYSTICK ACTIONS
DOWN
(towards you)

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b) LOADING BATTERIES
To load the batteries, remove the battery back door at the rear of the instrument
by applying a ¼ turn to the door latch. Insert the two rechargeable D-cell
batteries with the "+" to the small brass ring and the “-“ to the spring. The
fabric strip should be placed BEHIND the batteries to aid in their removal (see
fig). Ensure that both batteries are firmly seated, attach the plastic battery
retainer clip properly then re-attach the door. (Be sure that the door is properly
attached)
c) POWER ON
To switch the unit on, CLICK DOWN (towards the user) for at least 2
seconds. The display will come on and show Fig. 1A for a few seconds.
The unit is carrying out internal testing to verify that the units’ components
are functioning correctly during this display.
Fig. 1A
After approx. 3 seconds this display will be replaced by the normal startup
display shown in Fig. 1B and an audio beep will be heard.
If any errors are detected, they are displayed (see Appendix E). If no
errors are found, the display will change to the start up screen (Fig. 4)
shown below after a few seconds
Fig. 1B
MANUAL MODE ACTIVE – shows that the unit is in the MANUAL mode that permits full unit
functionality
d) BACKLITE ON
A BACKLITE option is built into the GR-135 such that the display may be viewed in low light
conditions. BACKLITE can be enabled in the system setup for frequent use or activated manually for
intermittent use. To enable the BACKLITE, be sure that the unit is OFF, then CLICK DOWN
(towards the user) and HOLD the JOYSTICK in this position. After about 3 seconds the display will
be illuminated (BACKLITE switches ON), after which the JOYSTICK may be released. The BACKLITE
will remain active until the unit is powered OFF. The GR-135 has a built-in battery saving feature
such that the BACKLITE will not turn ON if the battery voltage is below 2.2 V. This low voltage
indicates that there is little battery life left so disabling the BACKLITE feature allows the user to use
the remaining battery life optimally.
Note that to turn off the BACKLITE, the unit must be switched OFF then switched ON again with the
normal short click
The BACKLITE feature may be selected to be ON all the time for some applications or for set periods
of time as described in the SETUP section (Section 10) but users should be aware that enabling the
BACKLITE feature reduces battery life by an estimated 50%.
TESTING
EXPLORANIUM
GR-135
The IDENTIFIER
VERSION 109
SER# 2001
MANUAL MODE ACTIVE

SAIC Exploranium – GR-135 System Manual page: 15
e) POWER OFF - MANUAL
To power the unit OFF, CLICK UP (away from the user) and hold for
approx. 5 seconds. The display (Fig. 2) shows the seconds counting
down; 3, 2, 1. After this countdown the unit powers OFF. At any time
during the countdown, releasing the JOYSTICK will cancel the power
OFF.
Fig. 2
f) LOW BATTERY WARNINGS
The Battery ICON at the top right of the display is used to provide the user with an idea of the
current battery status. Unfortunately rechargeable NiCd batteries exhibit a very flat discharge curve.
This means that for a very long period the battery voltage is almost constant and then it will
suddenly discharge very rapidly at the end of battery charge. This battery characteristic means that
it is not possible to display a fully accurate battery-life indication.
Exploranium recommends that it is a sensible precaution to carry a spare set of ALKALINE batteries
in the system pouch if extensive field operations are required, to act as a backup (but NOT for DS
operation!). This ensures that battery failure does not prevent data acquisition when required.
For convenience, most users tend to use the NiCd rechargeable batteries. To provide some level of
warning of imminent battery life - if the batteries fall below a certain level then a 3-beep audio
occurs and the Battery ICON changes to the message LOW. The user has between 2 and 10
minutes of measuring time left in the battery at this time. When there is no longer enough power to
allow measuring, the GR-135 turns off.
Full Charge ½ Charge Low Battery Warning
Fig. 3
5.3 SWITCHING FROM AUTOMATIC MODE TO MANUAL MODE
With the unit set up correctly and being operated by the user, it is important to ensure that no one
changes the system settings in an unauthorized manner. For this reason there is a “hidden” slider
switch in the battery compartment used to select modes. (On more recent models the slider switch
is located behind the battery door on the right hand side – see Figure on page 8).
The slider switch has 2 modes labeled “A” for AUTOMATIC mode and “M” for MANUAL mode. With
the unit switched OFF, the user should select the mode of operation then power the unit ON to
activate the mode.
LOW
TURNING OFF
3(2,1..)
NOTE
LIKE ALL COMPUTER BASED SYSTEMS THERE IS A SLIGHT POSSIBILITY
THAT AN UNEXPECTED COMBINATION OF USER ACTIONS COULD CAUSE THE
SYSTEM TO HANG UP.
WHILE HIGHLY UNLIKELY, USERS ARE ADVISED THAT IF UNUSUAL
ACTIONS OCCUR - SWITCH THE UNIT OFF AS DESCRIBED IN (e) ABOVE AND
AT THE NEXT POWER ON THE SYSTEM SHOULD BE OK.

SAIC Exploranium – GR-135 System Manual page: 16
5.4 DISPLAY CONTRAST
When the unit is first turned ON, the user may use the joystick to adjust the Display Contrast to suit
themselves. Clicking LEFT changes contrast to lighter, clicking RIGHT changes contrast to darker.
The control is limited to 10 steps in either direction and when extremes are reached, an audio
double-beep is heard to advise the user that they are at the limit of adjustment. Note that the user-
set display contrast will be retained even when the unit is powered OFF.
After the initial contrast setting by the user, the contrast is automatically adjusted by
temperature compensation using an internal temperature sensor.
5.5 MAIN MENU
After the initial start-up screen, the GR-135 Main Menu appears.
The user may scroll through the menu items by a short click UP or
click DOWN. Reverse “highlighting” shows the current menu item
selected.
Menu items are selected by highlighting the desired item and using
ENTER to activate the selection.
Fig. 4
NOTE
Manual contrast adjustment is only enabled during the first 60 seconds
after power on. This is to prevent inadvertent contrast adjustment
during other system operations. 60 seconds is usually long enough for
adjusting contrast, however if further adjustment is required, switch
the unit off then on again to obtain another 60-second adjustment
id
SEARCH + DOSE
IDENTIFY
STABILIZE
DATA MEMORY
SETUP
MAINTENANCE
MAIN MENU
USER ADVISORY
Some users switch the unit ON
And see NO DISPLAY.
This is usually because they have set the CONTRAST
completely wrong.
If a greenish-colored blank display is seen, switch the unit
OFF (UP for 5 seconds ensures the unit is switched OFF).
Now power ON, wait 5 seconds, then RIGHT click the
Joystick repeatedly. 5-6 clicks is usually enough to restore
the display CONTRAST – the display should now be visible.
If the display is blue, then repeat the above procedure but
click the Joystick LEFT.
Contact Exploranium if the display is still blank.

SAIC Exploranium – GR-135 System Manual page: 17
5.6 STABILIZATION
The GR-135 is designed to automatically carry out system stabilization in the AUTOMATIC mode in
the DOCKING STATION. Once this has been done correctly then internal temperature correction is
used to maintain this level even if the unit has not been stabilized for many hours.
However in the MANUAL mode the system must be stabilized manually using the functions
described in section 7.
If the unit decides that Stabilization is required then a STABILIZATION WARNING display will be
shown – see Fig. 5.
If DEFAULT PARAMETERS are loaded then this warning will be seen as Stabilization is required
before the SEARCH and IDENTIFY functions.
Fig.5
5.7 EXTERNAL AUDIO
On the rear of the unit is a special connector as
shown in the rear view of the instrument shown in
the figure (external audio). Normally this
connecter is fitted with a sealing plug for weather
protection. However users with the optional
external earphone can plug it into this socket.
When this occurs the internal audio is silenced and
the audio tones are only audible through the
external earphone.
This silencing of the units audio is especially useful
in covert audio scanning or when the operator
does not wish to alarm anyone with sudden audio
tone increases
IT IS EXTREMELY IMPORTANT THAT
STABILIZATION BE CARRIED OUT IF REQUIRED
AFTER LOADING DEFAULT PARAMETERS - THE ACT
OF STABILIZATION SETS ALL THE SYSTEM
COMPUTATIONAL REQUIREMENTS FOR CARRYING
OUT THE IDENTIFY FUNCTION. WITHOUT THIS
STABILIZATION SERIOUS DATA ANALYSIS ERRORS
WILL OCCUR!
SEE THE FOLLOWING SECTIONS
FOR DETAILS ON OTHER FUNCTIONS
EXTERNAL
AUDIO

SAIC Exploranium – GR-135 System Manual page: 18
6.0 SEARCH+DOSE
6.1 SEARCH MODE
Select this menu item then ENTER to activate – fig. 6 is seen
SEARCH - Shows that the system is in the SEARCH mode.
- The Battery Icon shows battery status.
TOTAL - Shows that the SEARCH mode is using the full Total
Count data. See Section 9.1 for use with special ROI
data.
1234 - Is the current count rate in counts per second (cps)
updated every sample period. Fig. 6
MEAS - means unit is measuring (STOP means it is not measuring)
VS 2K - This is the vertical scale of the “chart-recorder” (in this case 2000cps). Most users let
the unit auto-scale but the user can manually set a fixed scale in SETUP – section 9.1
CHART RECORDER - The data in the data box shows the last 126 samples of data in a “chart-
recorder” format (left to right with the most current data on the LEFT). Therefore, at
a one second data rate, 126 seconds of data are displayed OR at a five second data
rate, 630 seconds of data are displayed etc. The Chart Recorder display is updated at
the end of every sample period.
D.RATE - is the current DOSE RATE in selected units – see Section 9.4 for more details
DOSE - is the TOTAL DOSE accumulated from the point in time SEARCH+DOSE mode was
activated – see Section 9.4 for more details
STOP – to stop this function press ENTER and the display will go back to the Main Menu. If the
user presses AND HOLDS the joystick in the ENTER position, the display will stop updating
and permit the user to inspect the data. Releasing the joystick goes back to the menu.
6.2 HIGH DOSE
The system has a preset maximum Dose Rate level – normally set at 2000uR/h. Below this level
Dose Rates are considered acceptable for system operation. However above this level it is
recommended that users move away from the source of radiation to reduce this Dose Rate level
to an acceptable level. To make things simple, the GR-135 advises the users automatically if the
Dose Rate level goes above the preset limit.
If this level is exceeded a distinctive audio warning tone occurs and the
display changes (fig 7) :
As noted, the user should back away until the Dose Rate level falls below
this limit and the display warning goes away.
Users should be reminded that short-term operation close to the limit has Fig. 7
a negligible hazard level but prolonged operation significantly above this level is not
recommended
HI RADIATION
DOSE RATE
MOVE AWAY!!
WARNING!!
MEAS
VS 2K
TOTAL 1234
RATE
1.3mR/h
DOSE
125uR/h
SEARCH
NAI

SAIC Exploranium – GR-135 System Manual page: 19
6.3 NEUTRON ALARM
The system has a selectable Neutron Alarm Threshold (for settings see
Section 10.3). If this level is exceeded a distinctive audio warning tone
occurs and the display changes (fig 8).
This display will stay on the screen as long as the Neutron data is above the
threshold and for 5 seconds after the data drops below the alarm
threshold to ensure that the user can inspect the data adequately.
Fig. 8
6.4 SEARCH ALARM
If the ALARM LEVEL parameter (section 10.1) is set to a preset value and
the radiation field exceeds this value, a distinct audio beep will be heard and a
pop-up box will appear as shown in the figure. As the user moves away from
the source the audio and pop-up display will go away.
Fig. 9
6.5 SEARCH - AUDIO
In the SEARCH mode the radiation data from the high-sensitivity Sodium-Iodide (NaI) detector is
used to create an audio search capability thus permitting the user to have an “eyes-free”
operational mode. It is very difficult to scan a vehicle and inspect the display continuously.
The GR-135 scans the incoming data at a 20 TIMES a SECOND RATE – and converts the
radiation field into a mode that changes the frequency of the audio tone to reflect the radiation
field intensity. Various parameters are used (see section 10 for details) to adjust system
performance to suit the user. In the majority of cases the audio gives occasional “beeps” of low
intensity audio on normal background (this shows the user that the audio system is alive) but in
the presence of a real radioactive field the audio frequency changes rapidly. With this feature it
is very easy to scan back and forwards to readily locate the highest audio pitch which is the
maximum radiation intensity.
6.6 SEARCH MODE - DATA RECORDING
The data displayed during the SEARCH mode can be recorded in memory. Recording to memory is
implemented by menu selection in the SETUP - SEARCH menu (Section 9.1). When the “OUTPUT
TO” parameter is set to “MEM” and the SEARCH mode is started, the data is logged into memory at
the selected Sample Rate. The message SEARCH->MEM will be displayed at the top of the screen
during the SEARCH to indicate that the data is being saved to memory.
Data recording is terminated when the memory is full or the mode is stopped (ENTER). Every time
the SEARCH mode is stopped then started again, a new header is written so the data can be
retrieved later with the appropriate time information. Remember that all SEARCH data will be loaded
into memory until the data recording option is disabled in SETUP mode.
The data memory can record approximately 45,000 readings at the selected data rate. Thus, at a
one sample per second data rate, the memory will hold almost 12.5 hours of SEARCH+DOSE data.
Once the GR-135 memory is full the message MF (memory full) will be displayed at the top of the
screen and the user gets a 3-beep audio warning and the SEARCH>MEM label is removed.
NEUTRONS
DETECTED
WARNING
ALARM
ABOVE
LIMIT
WARNING!!

SAIC Exploranium – GR-135 System Manual page: 20
The user should be aware that at the beginning of each new SEARCH mode activation, a header is
stored in memory. This header uses memory space equivalent to 6 SEARCH samples. Therefore, if a
large number of separate SEARCH samples are stored in memory, slightly less memory is available
for samples than if the SEARCH was taken in one complete set.
When the internal DATA MEMORY is full as described above, users should return to MAIN MENU
(ENTER) and dump the data to an external PC as detailed in Appendix B
To log data directly to a PC refer to Appendix B