Spektrum STX3 User Manual

NOTICE

All instructions, warranties and other collateral documents are subject to change at the sole discretion of Horizon Hobby, LLC. For
up-to-date product literature, visit horizonhobby.com or towerhobbies.com and click on the support or resources tab for this product.

Meaning of Special Language

The following terms are used throughout the product literature to indicate various levels of potential harm when operating this product:
WARNING: Procedures, which if not properly followed, create the probability of property damage, collateral damage, and

serious injury OR create a high probability of superficial injury.
CAUTION: Procedures, which if not properly followed, create the probability of physical property damage AND a possibility

of serious injury.
NOTICE: Procedures, which if not properly followed, create a possibility of physical property damage AND a little or no

possibility of injury.

WARNING: Read the ENTIRE instruction manual to become familiar with the features of the product before operating.
Failure to operate the product correctly can result in damage to the product, personal property and cause serious injury.

This is a sophisticated hobby product. It must be operated with caution and common sense and requires some basic
mechanical ability. Failure to operate this Product in a safe and responsible manner could result in injury or damage to the
product or other property. This product is not intended for use by children without direct adult supervision. Do not attempt
disassembly, use with Incompatible components or augment product in any way without the approval of Horizon Hobby, LLC.
This manual contains instructions for safety, operation and maintenance. It is essential to read and follow all the instructions
and warnings in the manual, prior to assembly, setup or use, in order to operate correctly and avoid damage or serious injury.

WARNING AGAINST COUNTERFEIT PRODUCTS: Always purchase from a Horizon Hobby, LLC authorized dealer to ensure
authentic high-quality Spektrum product. Horizon Hobby, LLC disclaims all support and warranty with regards, but not limited

to, compatibility and performance of counterfeit products or products claiming compatibility with DSM or Spektrum technology.

Age Recommendation: Not for Children under 14 years. This is not a toy.

NOTICE: This product is only intended for use with unmanned, hobby-grade, remote-controlled vehicles. Horizon Hobby

disclaims all liability outside of the intended purpose and will not provide warranty service related thereto.

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WARRANTY REGISTRATION

Visit www.spektrumrc.com/registration today to register your product.

SAFETY PRECAUTIONS

• Always ensure all batteries have been properly charged
prior to using the model.

• Always check all servos and their connections prior to each run.

• Never operate your model near spectators, parking areas
or any other area that could result in injury to people or
damage of property.

• Never operate your model during adverse weather
conditions. Poor visibility can cause disorientation and
loss of control of your model.

• Never point the transmitter antenna directly toward the

• If at any time during the operation of your model you

WATER-RESISTANT COMPONENT

Your new SRX300 Receiver has a special water-resistant
coating on the electronics to ensure reliable performance in
higher than average moisture conditions. This conformal coating
can offer mild protection from light drops of water.

• DO NOT submerge this product under water for any period

of time. If it is submerged, it may result in damage or loss of
function.

• DO NOT pour water onto or allow excess water to come in

direct contact with the product.

• DO NOT operate this product in heavy rain or snow.

• DO NOT expose this product to salt water (ocean water or

In case of excess exposure to water or debris, immediately
wipe down the SRX300 with a soft cloth, and allow it to fully
dry before next use.

NOTICE: Never use a pressure washer to clean your vehicle.
NOTICE: Make sure the other components in your vehicle are

waterproof or water-resistant before driving in wet conditions.

model. The radiation pattern from the tip of the antenna is
inherently low.

observe any erratic or abnormal operation, immediately
stop operation of your model until the cause of the
problem has been ascertained and corrected.

water on salt-covered roads), contaminated or polluted water.

1SPEKTRUM STX3 USER GUIDE

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INSTALLING THE TRANSMITTER BATTERIES

This transmitter requires 4 AA batteries.

1. Remove the battery cover from the
transmitter.

2. Install the batteries as shown.

3. Install the battery cover.

CAUTION: If using rechargeable batteries, charge only rechargeable batteries. Charging non-rechargeable batteries
may cause the batteries to burst, resulting in injury to persons and/or damage to property.

CAUTION: Risk of explosion if battery is replaced by an incorrect type. Dispose of used batteries according to
national regulations.

TRANSMITTER FUNCTIONS

A. Servo Reversing

To reverse the Throttle (TH) or Steering (ST) channel, switch
the position of the correlating switch—“N” is for normal, “R”
is for reverse.

B. Throttle Trim

Adjusts the throttle neutral point

C. Steering Trim

Adjusts the steering center point. Normally, the steering trim is
adjusted until the vehicle tracks straight.

D. Throttle Rate

Adjusts the end point of the throttle

E. Steering Rate

Adjusts the end point of the steering

F. Indicator Lights

• Solid red lights: Indicates radio connectivity and

adequate battery power

• Flashing red lights: Indicates the battery voltage is

critically low. Replace batteries

G. Throttle Limit

Limits throttle output to 50/75/100%
Select 50% or 75% for less experienced drivers or when you
are driving the vehicle in a small area.

H. Antenna
I. Power Button
J. Throttle/Brake
K. Steering Wheel
L. Channel 3 Buttons: Top and Bottom

A

B

D

F

I

Top

L

Bottom

J

2.4GHZ DIGITAL
RADIO SYSTEM

C

E

G

H

K

SRX300 RECEIVER

Specifi cations

Type: FHSS 2.4GHz protocol
Dimensions (LxWxH): 35.8 x 23.6 x 14.3 mm)
Antenna Length: 8.27 in
Channels: 3
Weight: 8.8g
Band: 2.4GHz
Voltage Range: 3.5–9.6V

2 SPEKTRUM STX3 USER GUIDE

BINDING

Binding is the process of programming the receiver to recognize the GUID (Globally Unique Identifi er) code of a single
specifi c transmitter. The STX3™ transmitter and SPMSRX300 receiver are bound at the factory. If you need to rebind, follow
the instructions below.

1. Insert the bind plug in the BIND port on the receiver.

2. Connect a fully charged battery pack to the ESC.

3. Power on the ESC. The red receiver LED flashes, indicating the
receiver is in bind mode.

4. Center the ST TRIM and TH TRIM dials on the transmitter.

5. Turn and hold the steering wheel fully right, then power the
transmitter on.

6. When the receiver LED stops flashing, release the steering wheel.

7. Remove the bind plug, then power off the receiver to save the settings.

8. Power off the transmitter.

9. Store the bind plug in a convenient place.

You must rebind when:

• Different failsafe positions are desired e.g., when throttle or steering reversing has been changed.

• Binding the receiver to a different transmitter.

MULTIFUNCTION PROGRAMMING

Channel 3 has four mode options available; 2-position,
3-position, 4-position and proportional (default).

To program channel 3 as a 2-position channel:

1. Press and hold the CH3 top button, then power ON the
transmitter. The left LED will glow solid and the right LED will
quickly fl ash once and then fl ash 5 times. Continue to hold the
top button until the right LED fl ashes 5times.

2. Release the top button.

3. Use the CH3 top and bottom buttons to adjust the
accessory/servo to the desired fi rst position.

4. When the fi rst position is reached, turn the steering wheel
clockwise (right) to save position 1. The LED will fl ash once
to confi rm position 1 has been saved.

5. Use the CH3 buttons to adjust the accessory/servo to the
desired second position.

6. When the second position is reached, turn the steering
wheel clockwise to confi rm position 2. The LED will fl ash
twice to confi rm position 2 has been saved.

7. Turn off the transmitter to save the CH3 settings.

To program channel 3 as a 3-position channel:

1. Press and hold the CH3 top button, then power ON the
transmitter. The left LED will glow solid and the right LED will
quickly fl ash once and then fl ash 5 times. Continue to hold the
top button until the right LED fl ashes 5times.

2. Release the top button.

3. Use the CH3 top and bottom buttons to adjust the
accessory/servo to the desired fi rst position.

4. When the fi rst position is reached, turn the steering wheel
clockwise (right) to save position 1. The LED will fl ash once
to confi rm position 1 has been saved.

5. Repeat steps 3 and 4 to defi ne the second and third
positions. The LED will fl ash twice for the second position
and three times for the third position when saved.

6. Turn off transmitter to save the CH3 settings.

To program channel 3 as a 4-position channel:

1. Press and hold the CH3 top button, then power ON the
transmitter. The left LED will glow solid and the right LED will
quickly fl ash once and then fl ash 5 times. Continue to hold the
top button until the right LED fl ashes 5times.

2. Release the top button.

3. Use the CH3 top and bottom buttons to adjust the
accessory/servo to the desired fi rst position.

4. When the fi rst position is reached, turn the steering wheel
clockwise (right) to save position 1. The LED will fl ash once
to confi rm position 1 has been saved.

5. Repeat steps 3 and 4 to defi ne positions 2-4. The LED will fl ash
a corresponding number of times for each saved position.

6. Turn off transmitter to save the CH3 settings.

To program channel 3 as a proportional channel (default):

1. Press and hold the CH3 top button, then power ON the
transmitter. The left LED will glow solid and the right LED
will immediately fl ash once. Release the top button as soon
as the right LED goes out.
IMPORTANT: If the top button is held too long, the
transmitter will enter 2, 3, 4-position CH3 programming
mode, indicated by 5 fl ashes. Power the transmitter off and
begin again.
When the top button is released, the right LED will glow
solid, indicating channel 3 is in proportional mode.

2. Turn off transmitter to save the CH3 settings.

TIPS:

• Press and hold the CH3 push buttons to quickly adjust the
output position. Press and release to make smaller adjustments.

• The fi rst selected position and the last selected position
will always be the maximum travel end points for CH3.

• Moving the steering wheel during adjustment of CH3 will
save the current position. Do not move the steering wheel
unless the position is ready to be saved.

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3SPEKTRUM STX3 USER GUIDE

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End Point Adjustments

Steering End Points:

1. Enter programming mode by turning and holding the wheel
fully right (clockwise), holding full throttle (fully back) and
powering on the transmitter. The right LED will fl ash 5
times. Release the wheel and the trigger.

2. Fully turn and hold the wheel to the left (counterclockwise).
While holding the wheel fully left, press the CH3 push buttons
to adjust the proper left end point position.

3. Fully turn and hold the wheel to the right (clockwise).While
holding the wheel fully right, press the CH3 push buttons to
adjust the proper right end point position.

4. Release the steering wheel.

5. Power off the transmitter to save the settings.

Throttle End Points:

1. Enter programming mode by turning and holding the wheel
fully right (clockwise), holding full throttle (fully back) and
powering on the transmitter. The right LED will fl ash 5
times. Release the wheel and the trigger.

2. Pull the throttle trigger fully back. While holding the throttle
trigger, press the CH3 push buttons to adjust the proper full
throttle position.

3. Push the throttle trigger fully forward to set the maximum
brake end point. While holding the throttle trigger, press the
CH3 push buttons to adjust the proper full brake position.

4. Release the throttle trigger.

5. Power off the transmitter to save the settings.

2.4GHz TROUBLESHOOTING GUIDE

Problem Possible Cause Solution

Your transmitter and receiver are too close together Move transmitter 1 to 3 meters from receiver

The system will not
connect

The receiver goes into
failsafe mode a short
distance away from the
transmitter

The receiver quits
responding during
operation

You are around metal objects Move to an area with less metal

The model selected is not the model bound to

Your transmitter was accidentally put into bind
mode and is no longer bound to your receiver

Check the receiver antenna to be sure it is not
cut or damaged

Inadequate battery voltage

Loose or damaged wires or connectors between
battery and receiver

Check model selected and ensure you are bound
to that model

Rebind your transmitter and receiver

Replace the receiver or contact Horizon Product
Support

Make sure your receiver antenna is in an antenna
tube and is above the vehicle

Charge batteries. Spektrum receivers require at
least 3.5V to operate. An inadequate power supply
can allow voltage to momentarily drop below 3.5V
and cause the receiver to brown out and reconnect

Check the wires and connection between the battery
and receiver. Repair or replace wires and/or connectors

1 YEAR LIMITED WARRANTY

What this Warranty Covers

Horizon Hobby, LLC, (Horizon) warrants to the original
purchaser that the product purchased (the “Product”) will be
free from defects in materials and workmanship for a period
of 1 year from the date of purchase.

What is Not Covered

This warranty is not transferable and does not cover (i)
cosmetic damage, (ii) damage due to acts of God, accident,
misuse, abuse, negligence, commercial use, or due to
improper use, installation, operation or maintenance, (iii)
modifi cation of or to any part of the Product, (iv) attempted
service by anyone other than a Horizon Hobby authorized
service center, (v) Product not purchased from an authorized
Horizon dealer, (vi) Product not compliant with applicable
technical regulations, or (vii) use that violates any applicable
laws, rules, or regulations.
OTHER THAN THE EXPRESS WARRANTY ABOVE, HORIZON
MAKES NO OTHER WARRANTY OR REPRESENTATION, AND
HEREBY DISCLAIMS ANY AND ALL IMPLIED WARRANTIES,
INCLUDING, WITHOUT LIMITATION, THE IMPLIED
WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE. THE
PURCHASER ACKNOWLEDGES THAT THEY ALONE HAVE
DETERMINED THAT THE PRODUCT WILL SUITABLY MEET THE
REQUIREMENTS OF THE PURCHASER’S INTENDED USE.

4 SPEKTRUM STX3 USER GUIDE

Purchaser’s Remedy

Horizon’s sole obligation and purchaser’s sole and exclusive
remedy shall be that Horizon will, at its option, either (i)
service, or (ii) replace, any Product determined by Horizon
to be defective. Horizon reserves the right to inspect any
and all Product(s) involved in a warranty claim. Service or
replacement decisions are at the sole discretion of Horizon.
Proof of purchase is required for all warranty claims. SERVICE
OR REPLACEMENT AS PROVIDED UNDER THIS WARRANTY IS
THE PURCHASER’S SOLE AND EXCLUSIVE REMEDY.

Limitation of Liability

HORIZON SHALL NOT BE LIABLE FOR SPECIAL, INDIRECT,
INCIDENTAL OR CONSEQUENTIAL DAMAGES, LOSS OF PROFITS OR
PRODUCTION OR COMMERCIAL LOSS IN ANY WAY, REGARDLESS
OF WHETHER SUCH CLAIM IS BASED IN CONTRACT, WARRANTY,
TORT, NEGLIGENCE, STRICT LIABILITY OR ANY OTHER THEORY
OF LIABILITY, EVEN IF HORIZON HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES. Further, in no event shall the
liability of Horizon exceed the individual price of the Product on
which liability is asserted. As Horizon has no control over use, setup,
fi nal assembly, modifi cation or misuse, no liability shall be assumed
nor accepted for any resulting damage or injury. By the act of use,
setup or assembly, the user accepts all resulting liability. If you as the
purchaser or user are not prepared to accept the liability associated
with the use of the Product, purchaser is advised to return the Product
immediately in new and unused condition to the place of purchase.

Law

These terms are governed by Illinois law (without regard to
confl ict of law principals). This warranty gives you specifi c
legal rights, and you may also have other rights which vary
from state to state. Horizon reserves the right to change or
modify this warranty at any time without notice.

WARRANTY SERVICES
Questions, Assistance, and Services

Your local hobby store and/or place of purchase cannot
provide warranty support or service. Once assembly, setup or
use of the Product has been started, you must contact your
local distributor or Horizon directly. This will enable Horizon to
better answer your questions and service you in the event that
you may need any assistance.
For questions or assistance, please visit our website at
www.horizonhobby.com, submit a Product Support Inquiry, or
call the toll free telephone number referenced in the Warranty
and Service Contact Information section to speak with a
Product Support representative.

Inspection or Services

If this Product needs to be inspected or serviced and is
compliant in the country you live and use the Product in,
please use the Horizon Online Service Request submission
process found on our website or call Horizon to obtain a
Return Merchandise Authorization (RMA) number. Pack the
Product securely using a shipping carton. Please note that
original boxes may be included, but are not designed to
withstand the rigors of shipping without additional protection.
Ship via a carrier that provides tracking and insurance for
lost or damaged parcels, as Horizon is not responsible for
merchandise until it arrives and is accepted at our facility.
An Online Service Request is available at http://www.
horizonhobby.com/content/service-center_render-service­center. If you do not have internet access, please contact
Horizon Product Support to obtain a RMA number along with
instructions for submitting your product for service. When
calling Horizon, you will be asked to provide your complete
name, street address, email address and phone number
where you can be reached during business hours. When
sending product into Horizon, please include your RMA

EN

number, a list of the included items, and a brief summary
of the problem. A copy of your original sales receipt must
be included for warranty consideration. Be sure your name,
address, and RMA number are clearly written on the outside
of the shipping carton.

NOTICE: Do not ship LiPo batteries to Horizon. If you
have any issue with a LiPo battery, please contact the
appropriate Horizon Product Support offi ce.

Warranty Requirements

For Warranty consideration, you must include your original
sales receipt verifying the proof-of-purchase date. Provided
warranty conditions have been met, your Product will be
serviced or replaced free of charge. Service or replacement
decisions are at the sole discretion of Horizon.

Non-Warranty Service

Should your service not be covered by warranty, service
will be completed and payment will be required without
notifi cation or estimate of the expense unless the expense
exceeds 50% of the retail purchase cost. By submitting
the item for service you are agreeing to payment of the
service without notifi cation. Service estimates are available
upon request. You must include this request with your item
submitted for service. Non-warranty service estimates will
be billed a minimum of ½ hour of labor. In addition you will
be billed for return freight. Horizon accepts money orders
and cashier’s checks, as well as Visa, MasterCard, American
Express, and Discover cards. By submitting any item to
Horizon for service, you are agreeing to Horizon’s Terms and
Conditions found on our website http://www.horizonhobby.
com/content/service-center_render-service-center.

ATTENTION: Horizon service is limited to Product

compliant in the country of use and ownership. If
received, a non-compliant Product will not be serviced.
Further, the sender will be responsible for arranging return
shipment of the un-serviced Product, through a carrier of the
sender’s choice and at the sender’s expense. Horizon will
hold non-compliant Product for a period of 60 days from
notifi cation, after which it will be discarded.

10/2015

WARRANTY, SERVICE AND CUSTOMER SERVICE CONTACT INFORMATION

Country of

Purchase

North America

European Union

Horizon Hobby Phone Number/Email Address Address

Horizon Service Center

(Repairs and Repair Requests)

Horizon Product Support

(Product Technical Assistance)

Sales

Horizon Technischer Service [e-mail]
Sales: Horizon Hobby GmbH [phone]

servicecenter.horizonhobby.com/

RequestForm/

[e-mail]

877-504-0233

[e-mail]

800-338-4639

Champaign, Illinois, 61822 USA

D 22885 Barsbüttel, Germany

2904 Research Rd

Hanskampring 9

5SPEKTRUM STX3 USER GUIDE

EN

FCC INFORMATION

FCC ID: BRWSTX3

FCC NOTE: 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.

NOTE: THE GRANTEE IS NOT RESPONSIBLE FOR ANY
CHANGES OR MODIFICATIONS NOT EXPRESSLY APPROVED
BY THE PARTY RESPONSIBLE FOR COMPLIANCE. SUCH
MODIFICATIONS COULD VOID THE USER’S AUTHORITY TO
OPERATE THE EQUIPMENT.

For a Class B digital device or peripheral, the instructions
furnished the user shall include the following or similar
statement, placed in a prominent location in the text of the
manual:

NOTE: 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.

The device has been evaluated to meet general RF exposure
environment.

To maintain compliance with FCC’s RF exposure guidelines,
the distance must be at least 20cm between the radiator
and your body, and fully supported by the operating and
installation configurations of the transmitter and its antenna(s)

IC INFORMATION

IC: 6157A-STX3

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.

COMPLIANCE INFORMATION FOR THE EUROPEAN UNION

Horizon Hobby, LLC hereby declares that this
product is in compliance with the essential
requirements and other relevant provisions of

the RED Directive.
A copy of the EU Declaration of Conformity is available online at:
http://www.horizonhobby.com/content/support-render-compliance.

Frequency Band: 2405-2474 MHz
Max EIRP: 8.30 dBm

collection point for the recycling of waste electrical and
electronic equipment. The separate collection and recycling
of your waste equipment at the time of disposal will help to
conserve natural resources and ensure that it is recycled in
amanner that protects human health and the environment.
For more information about where you can drop off your
waste equipment for recycling, please contact your local city
offi ce, your household waste disposal service or where you
purchased the product.

Instructions for Disposal of WEEE
by Users in the European Union

This product must not be disposed
of with other waste. Instead, it is the
user’sresponsibility to dispose of their waste
equipment by handing it over to adesignated

6 SPEKTRUM STX3 USER GUIDE

© 2019 Horizon Hobby, LLC.
DSM, DSM2, DSMR and the Horizon Hobby logo are registered trademarks of Horizon Hobby, LLC.
The Spektrum trademark is used with permission of Bachmann Industries, Inc.
Created: 6/2019 SPMSTX300 60412.1