Vernier Go Direct GDX-EA User manual

1
Wireless Devices. Your sensor's ID
is located near the barcode on the
sensor. The Bluetooth LED will
blink green when it is successfully
connected.
8. This is a multi-channel sensor. The
active channel is listed in the
Connected Devices Sensor
Channels list. To change channels,
select the check box next to the
Sensor Channel(s) you would like
to activate.
9. Click or tap Done to enter
data-collection mode.
Note: This sensor does not work with
the original LabQuest. It works with
LabQuest 2 or LabQuest 3.
Charging the Sensor
Connect the Go Direct Electrode Amplifier to the included USB micro cable and
any USB device for two hours.
You can also charge up to eight Go Direct Electrode Amplifiers using our Go
Direct Charge Station, sold separately (order code: GDX-CRG).
Charging Blue LED is on steady while sensor is connected
to the Charging Cable or Charge Station.
Fully charged Blue LED is off when charging is complete.
Powering the Sensor
Turning on the sensor Press button once. Red LED indicator flashes
when unit is on.
Putting the sensor in sleep
mode
Press and hold button for more than three seconds
to put into sleep mode. Red LED indicator stops
flashing when sleeping.
Go Direct®Electrode
Amplifier
(Order Code GDX-EA)
Use our Go Direct Electrode Amplifier to collect data with almost
any electrode that has a BNC connector. This includes electrodes
from Vernier, such as our pH electrodes, ion-selective electrodes
(ISE), or oxidation-reduction potential (ORP) electrode. The Go
Direct Electrode Amplifier can produce an output in mV, pH (when using a pH
electrode).
Note: Vernier products are designed for educational use. Our products are not
designed nor are they recommended for any industrial, medical, or commercial
process such as life support, patient diagnosis, control of a manufacturing
process, or industrial testing of any kind.
What's Included
lGo Direct Electrode Amplifier
lMicro USBCable
Compatible Software
See www.vernier.com/manuals/gdx-ea for a list of software compatible with Go
Direct Electrode Amplifier.
Getting Started
Please see the following link for platform-specific connection information:
www.vernier.com/start/gdx-ea
Bluetooth Connection USB Connection
1. Connect a BNC electrode to the
amplifier.
2. Install Vernier Graphical Analysis®
on your computer, Chromebook™,
or mobile device. See
www.vernier.com/ga for software
availability.
3. Charge your sensor for at least
2hours before first use.
4. Turn on your sensor by pressing
the power button once. The
Bluetooth®LED will blink red.
5. Launch Graphical Analysis.
6. Click or tap Sensor Data
Collection.
7. Click or tap your Go Direct sensor
from the list of Discovered
1. Connect a BNC electrode to the
amplifier.
2. If using a computer or Chromebook,
install Graphical Analysis. If using
LabQuest, make sure LabQuest App
is up to date. See
www.vernier.com/ga for Graphical
Analysis availability or
www.vernier.com/downloads to
update LabQuest App.
3. Connect the sensor to the USB port.
4. Launch Graphical Analysis or turn on
LabQuest. You are now ready to
collect data.
5. This is a multi-channel sensor. To
change the default channel selections,
see www.vernier.com/start/gdx-ea

2
can always choose to restore factory defaults if you feel the custom calibration is
invalid.
If an ORP or ion-selective electrode is connected and you are measuring potential,
calibration is not required. Calibration is disabled in this mode to ensure the best
results.
Specifications
Units pH or mV
Input range (mV) ±1000 mV
Input range (pH) 0 to 14 pH
Accuracy with new electrode (mV) ±20 mV
Accuracy with new electrode (pH) ±0.2
Resolution 0.01 mV
Connections
Wireless
Wired
Bluetooth
USB
Care and Maintenance
Battery Information
Go Direct Electrode Amplifier contains a small lithium-ion battery in the handle.
The system is designed to consume very little power and not put heavy demands
on the battery. Although the battery is warranted for one year, the expected battery
life should be several years. Replacement batteries are available from Vernier
(order code: GDX-BAT-300).
Storage and Maintenance
To store Go Direct Electrode Amplifier for extended periods of time, put the
device in sleep mode by holding the power button down for at least three seconds.
The red LED will stop flashing to show that the unit is in sleep mode. Over
several months, the battery will discharge but will not be damaged. After such
storage, charge the device for a few hours, and the unit will be ready to go.
Exposing the battery to temperatures over 35°C (95°F) will reduce its lifespan. If
possible, store the device in an area that is not exposed to temperature extremes.
Water Resistance
Go Direct Electrode Amplifier is not water resistant and should never be immersed
in water.
If water gets into the device, immediately power the unit down (press and hold the
power button for more than three seconds). Disconnect the sensor and charging
cable, and remove the battery. Allow the device to dry thoroughly before
Connecting the Sensor
See the following link for up-to-date connection information:
www.vernier.com/start/gdx-ea
Connecting via Bluetooth
Ready to connect Red LED flashes when sensor is awake and ready
to connect.
Connected Green LED flashes when sensor is connected via
Bluetooth.
Connecting via USB
Connected and charging Blue and Green LEDs are solid when sensor is
connected to Graphical Analysis via USB and unit
is charging. (Green LED is obscured by the blue
one.)
Connected, fully charged Green LED is solid when sensor is connected to
Graphical Analysis via USB and the unit is fully
charged.
Charging via USB,
connected via Bluetooth
Blue LED is solid and green LED is flashing, but
the green flashing LED looks white because it is
overwhelmed by the blue.
Using the Product
Connect the sensor following the steps in the Getting Started section of this user
manual.
Channels
Go Direct Electrode Amplifier has two measurement channels:
lPotential
lpH
Calibration
If a pH electrode is attached, a two-point calibration is recommended for the most
accurate results. It is a simple process that takes only a few minutes. For additional
calibration information, see www.vernier.com/til/4011
In order to calibrate a pH electrode/electrode amplifier combination, or to confirm
that a saved pH calibration is accurate, you should have a supply of pH buffer
solutions that cover the range of the pH values you will be measuring. For more
information about pH buffer solutions, including recipes for preparation, see
www.vernier.com/til/3625
Once you have calibrated a Go Direct sensor, the calibration is automatically
stored to the sensor and will be used each time you connect to your device. You

3
be given to an applicable collection point for the recycling of electrical and
electronic equipment. By ensuring that this product is disposed of correctly, you
help prevent potential negative consequences on human health or on the
environment. The recycling of materials will help to conserve natural resources.
For more detailed information about recycling this product, contact your local city
office or your disposal service.
Battery recycling information is available at www.call2recycle.org
Do not puncture or expose the battery to excessive heat or flame.
The symbol, shown here, indicates that this product must not be disposed of in
a standard waste container.
Federal Communication Commission Interference Statement
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. 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 communications. However, there is no guarantee that interference will not 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 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.
FCC Caution
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference and
(2) this device must accept any interference received, including interference that may cause undesired operation
RF Exposure Warning
The equipment complies with RF exposure limits set forth for an uncontrolled environment. The antenna(s) used for this transmitter must not
be co-located or operating in conjunction with any other antenna or transmitter. You are cautioned that changes or modifications not
expressly approved by the party responsible for compliance could void your authority to operate the equipment.
IC Statement
This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions:
(1) this device may not cause interference, and
(2) this device must accept any interference, including interference that may cause undesired operation of the device.
Industry Canada - Class B This digital apparatus does not exceed the Class B limits for radio noise emissions from digital apparatus as set
out in the interference-causing equipment standard entitled “Digital Apparatus,” ICES-003 of Industry Canada. Operation is subject to the
following two conditions: (1) this device may not cause interference, and
(2) this device must accept any interference, including interference that may cause undesired operation of the device.
To reduce potential radio interference to other users, the antenna type and its gain should be so chosen that the equivalent isotropically
radiated power (e.i.r.p.) is not more than that permitted for successful communication.
RF exposure warning: The equipment complies with RF exposure limits set forth for an uncontrolled environment. The antenna(s) used for
this transmitter must not be co-located or operating in conjunction with any other antenna or transmitter.
Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de licence. L’exploitation est
autorisée aux deux conditions suivantes :
(1) l’appareil ne doit pas produire de brouillage, et
(2) l’appareil doit accepter tout interférence radioélectrique, même si cela résulte à un brouillage susceptible d’en compromettre le
fonctionnement.
Cet appareil numérique respecte les limites de bruits radioélectriques applicables aux appareils numériques de Classe B prescrites dans la
norme sur le matériel interférant-brouilleur: “Appareils Numériques,” NMB-003 édictée par industrie Canada. L’utilisation est soumise aux
deux conditions suivantes:
(1) cet appareil ne peut causer d’interférences, et
(2) cet appareil doit accepter toutes interférences, y comprises celles susceptibles de provoquer un disfonctionnement du dispositif.
attempting to use the device again. Do not attempt to dry using an external heat
source.
How the Sensor Works
Go Direct Electrode Amplifier is a circuit that allows the voltage output of the
electrode to be monitored. The electrode is connected to the BNC connector on
one end of the amplifier.
Go Direct Electrode Amplifier will default to report values in units of pH. If an
ORP or ISE electrode is attached, however, you can choose to read in units of mV.
For additional information, see www.vernier.com/til/3984
Troubleshooting
For troubleshooting and FAQs, see www.vernier.com/til/3858
Repair Information
If you have followed the troubleshooting steps and are still having trouble with
your Go Direct Electrode Amplifier, contact Vernier Technical Support at
[email protected] or call 888-837-6437. Support specialists will work with
you to determine if the unit needs to be sent in for repair. At that time, a Return
Merchandise Authorization (RMA) number will be issued and instructions will be
communicated on how to return the unit for repair.
Accessories/Replacements
Item Order Code
Go Direct pH BNC Electrode GDX-PH-BNC
Go Direct ORP BNC Electrode GDX-ORP-BNC
Go Direct Flat pH BNC Electrode GDX-FPH-BNC
Go Direct Glass-Body pH BNCElectrode GDX-GPH-BNC
Go Direct Potassium Ion-Selective Electrode BNC GDX-K-BNC
Go Direct Nitrate Ion-Selective Electrode BNC GDX-NO3-BNC
Go Direct Ammonium Ion-Selective Electrode BNC GDX-NH4-BNC
Go Direct Chloride Ion-Selective Electrode BNC GDX-CL-BNC
Go Direct Calcium Ion-Selective Electrode BNC GDX-CA-BNC
Micro USB Cable CB-USB-MICRO
Go Direct 300 mAh Replacement Battery GDX-BAT-300
USB-C to Micro USB Cable CB-USB-C-MICRO
Warranty
Warranty information for this product can be found on the Support tab at
www.vernier.com/gdx-ea
General warranty information can be found at www.vernier.com/warranty
Disposal
When disposing of this electronic product, do not treat it as household waste. Its
disposal is subject to regulations that vary by country and region. This item should

4
Afin de réduire les interférences radio potentielles pour les autres utilisateurs, le type d’antenne et son gain doivent être choisie de telle
façon que l’équivalent de puissance isotrope émis (e.i.r.p) n’est pas plus grand que celui permis pour une communication établie.
Avertissement d’exposition RF: L’équipement est conforme aux limites d’exposition aux RF établies pour un environnement non
supervisé. L’antenne (s) utilisée pour ce transmetteur ne doit pas être jumelés ou fonctionner en conjonction avec toute autre antenne ou
transmetteur.
Note: This product is a sensitive measurement device. For best results, use the cables that were provided. Keep the device away from
electromagnetic noise sources, such as microwaves, monitors, electric motors, and appliances.
Vernier Science Education
13979 SW Millikan Way • Beaverton, OR 97005-2886
Toll Free [phone] • [phone] • Fax [phone]
[email protected] • www.vernier.com
Rev. 2/15/2024
Go Direct, Vernier Graphical Analysis, LabQuest, and other marks shown are our trademarks or registered trademarks
in the United States. All other marks not owned by us that appear herein are the property of their respective owners,
who may or may not be affiliated with, connected to, or sponsored by us.
The Bluetooth®word mark and logos are registered trademarks owned by the Bluetooth SIG, Inc. and any use of such
marks by Vernier Science Education is under license. Other trademarks and trade names are those of their respective
owners.