JR X9303 2.4 Owner's manual

INSTRUCTION AND
PROGRAMMING MANUAL
X9303 2.4
9-CHANNEL COMPUTER RADIO
SYSTEM WITH SPEKTRUM 2.4GHz DSM
TECHNOLOGY

Table of Contents
G-2
Section 1: Using the Manual .........................................................................................................G-9
Features......................................................................................................................................................... G-9
Specications................................................................................................................................................ G-9
Section 2:Transmitter and Receiver Specifications.................................................................G-9
JR X9303 Transmitter..................................................................................................................................... G-9
JR R921 Receiver ..........................................................................................................................................G-10
Features.......................................................................................................................................................G-10
Specications..............................................................................................................................................G-10
Section 3: Component Specifications.......................................................................................G-11
Servo Specications......................................................................................................................................G-11
Charger Specifications .................................................................................................................G-11
Airborne Battery Pack.................................................................................................................G-11
Airborne Battery Pack Specications...................................................................................................G-11
Battery Charging...........................................................................................................................G-12
Transmitter/Receiver....................................................................................................................................G-12
JR Transmitter Charging...........................................................................................................................G-12
Using the Included Charger....................................................................................................................G-12
X9303 2.4 Transmitter Features (Mode 2 Airplane Shown)...............................................G-13
X9303 2.4 Transmitter Features (Rear)...................................................................................G-14
Battery Cover............................................................................................................................................G-14
X9303 2.4 Transmitter Features (Internal) .............................................................................G-15
Control Stick Tension Adjustment.............................................................................................................G-15
Back of Transmitter (Mode 2)................................................................................................................G-15
Advanced Digital Trims ................................................................................................................................G-16
Control Stick Length....................................................................................................................................G-16
Neckstrap Attachment.................................................................................................................................G-16
Installing the Receiver..................................................................................................................................G-17
Installing the JR R921 ...............................................................................................................................G-17
Model Match ..................................................................................................................................G-18
Other Important Installation Tips .........................................................................................................G-18
Binding .............................................................................................................................................G-19
How To Bind...................................................................................................................................................G-19
Fail-Safe Functions.........................................................................................................................................G-20
SmartSafe ........................................................................................................................................................G-20
Receiver Power Only...............................................................................................................................G-20
After Connection......................................................................................................................................G-20
Preset Fail-Safe...............................................................................................................................................G-20
Receiver Power Only...............................................................................................................................G-20
After Connection......................................................................................................................................G-20
Programming SmartSafe ..............................................................................................................................G-20
(All Spektrum Aircraft Receivers) .........................................................................................................G-20
Programming Preset Fail-Safe.....................................................................................................................G-21
(JR R921 and Spektrum AR 9000 Receivers Only) ...........................................................................G-21

Table of Contents
G-3
Standard Range Testing ................................................................................................................G-21
Range Testing the X9303 2.4 ..................................................................................................................G-21
Advanced Range Testing Using a Flight Log............................................................................G-22
Advanced Range Testing the X9303 2.4...............................................................................................G-22
Flight Log—Optional for JR R921 Receiver ...........................................................................G-23
Using the Flight Log..................................................................................................................................G-23
Receiver Power System Requirements....................................................................................G-24
Recommended Power System Guidelines...............................................................................................G-24
Flash Memory ................................................................................................................................G-25
Battery Alarm and Display..........................................................................................................G-25
Tip on Using 2.4GHz Systems...................................................................................................G-25
AIRPLANE – ACRO MODE......................................................................................................... A-1
Flight Modes..................................................................................................................................................A-1
ACRO PROGRAMMING - PLEASE READ ...........................................................................................A-1
ACRO - GETTING STARTED – SYSTEM MENU BASICS................................................................A-1
ACCESS THE SYSTEM MENU ......................................................................................................................A-2
SELECT A MODEL MEMORY.......................................................................................................................A-2
RESET THE MODEL........................................................................................................................................A-3
TO ACTIVATE THE ACRO MODE..............................................................................................................A-4
ENTER A NAME FOR THE MODEL...........................................................................................................A-4
ACRO - SYSTEM MENU - ADVANCED FUNCTIONS........................................................ A-5
FLIGHT MODES ..............................................................................................................................................A-6
To Activate Flight Modes ................................................................................................................................A-7
TRIM:COM (Flight Modes)............................................................................................................................A-8
D/R:SW (Flight Modes) ..................................................................................................................................A-8
SWITCH ASSIGNMENTS..............................................................................................................................A-9
FLAP TRIM ON/OFF.......................................................................................................................................A-9
ACTIVATE/INHIBIT SWITCHES............................................................................................................... A-10
WING TYPE................................................................................................................................................... A-11
WING Parameter – (Wing Type) .............................................................................................................. A-12
V-tail (Wing Type).......................................................................................................................................... A-14
Dual Channels (Wing Type) ........................................................................................................................ A-14
Twin E. (Wing Type) ...................................................................................................................................... A-16
TRIM STEP...................................................................................................................................................... A-18
ACRO – FUNCTION LIST.................................................................................................................... A-19
REV.SW – SERVO REVERSING ................................................................................................................ A-19
SUB TRIM........................................................................................................................................................ A-20
TRVL ADJ. – TRAVEL ADJUST ................................................................................................................... A-21
D/R & EXP – DUAL RATE AND EXPONENTIAL ............................................................................... A-22
THRO CURV – THROTTLE CURVE........................................................................................................ A-23
FLAP SYS. – FLAP SYSTEM......................................................................................................................... A-25
AUTO LAND (Flap System)....................................................................................................................... A-26
ELEV – ELEVATOR COMPENSATION (Flap System).......................................................................... A-27

Table of Contents
G-4
FLAP – (Flap System) ................................................................................................................................... A-28
FM0-FM2 (Flap System) ............................................................................................................................... A-29
Delay (Flap System) ...................................................................................................................................... A-30
ELEFLP M – ELEVATOR-TO-FLAP MIXING...................................................................................... A-31
AILRUD M – AILERON-TO-RUDDER MIXING ............................................................................. A-32
AIL DIFF. – AILERON DIFFERENTIAL ..................................................................................................... A-33
SRV. SPEED – SERVO SPEED...................................................................................................................... A-35
SNAP ROLL.................................................................................................................................................... A-36
GYRO SYS. – GYRO SYSTEM.................................................................................................................... A-37
GYRO CONNECTIONS (Gyro System)................................................................................................ A-37
FIXED GYRO GAIN (Gyro System)........................................................................................................ A-38
STICK OVERRIDE GYRO GAIN (Gyro System).................................................................................. A-39
PROG MIX – PROGRAMMABLE MIXERS ............................................................................................. A-40
STANDARD PROGRAMMABLE MIXER – Example: DOWN ELEVATOR AT IDLE..................... A-41
MULTI-POINT MIXER – Example: ELIMINATE PITCH-COUPLING............................................... A-43
TRAINER – TRAINER SYSTEM................................................................................................................. A-45
XP9303 USED AS MASTER (INSTRUCTOR) – (Trainer System)..................................................... A-45
X9303 2.4 USED AS SLAVE (STUDENT) – (Trainer System) ............................................................ A-46
TIMER – TIMER SYSTEM............................................................................................................................. A-47
MONITOR...................................................................................................................................................... A-48
UTILITY FUNCTIONS................................................................................................................................ A-49
COPY – COPY THE CURRENTLY SELECTED MODEL TO ANOTHER MODEL MEMORY... A-49
TRANSFER – TRANSFER THE MODEL TO ANOTHER TRANSMITTER OR TO DataSafe....... A-51
RECEIVE A MODEL INTO THE X9303 2.4 – (Transfer function)..................................................... A-51
RECEIVE A MODEL INTO THE X9303 2.4 – (Transfer function)..................................................... A-52
SUB TRIM USAGE AND MECHANICAL ADVANTAGE..................................................................... A-53
SUB TRIM.................................................................................................................................................... A-53
MECHANICAL ADVANTAGE............................................................................................................... A-53
DUAL RATES AND EXPONENTIAL CURVES ..................................................................................... A-54
Setup Sheet (Aircraft) .................................................................................................................................. A-55
X9303 2.4 Helicopter – Heli Mode ...........................................................................................H-1
INTRODUCTION...................................................................................................................................... H-1
Heli PROGRAMMING - PLEASE READ.................................................................................................... H-1
HELI - GETTING STARTED – SYSTEM MENU BASICS....................................................................... H-1
ACCESS THE SYSTEM MENU ..................................................................................................................... H-2
Model SEL- Model Selection......................................................................................................................... H-2
Copy – Copying the Currently Selected Model to Another Model Memory................................... H-3
Data Reset – RESET THE MODEL ............................................................................................................. H-5
Type Select – TO ACTIVATE THE HELI MODE....................................................................................... H-6
MDL Name-ENTER A NAME FOR THE MODEL................................................................................... H-6
TRANSFER – TRANSFER THE MODEL TO ANOTHER TRANSMITTER OR TO DATASAFE .... H-7
TRANSFER A MODEL FROM THE X9303 2.4 – (Transfer function) – To Send.............................. H-7
TRANSFER A MODEL TO THE X9303 2.4 – (Transfer function) – To Receive............................... H-8
TRIM STEP........................................................................................................................................................ H-9

Table of Contents
G-5
HELI - SYSTEM MENU - ADVANCED FUNCTIONS..........................................................................H-10
ADDITIONAL FLIGHT MODES 3 and 4 ...............................................................................................H-10
RUD TRIM: COM – (Flight Mode Trim Options)................................................................................... H-11
SWITCH ASSIGNMENTS...........................................................................................................................H-11
ACTIVATE/DEACTIVATE SWITCHES.....................................................................................................H-12
GOVERNOR PROGRAM ACTIVATION ................................................................................................ H-12
SWASH TYP-SWASHPLATE TYPE............................................................................................................H-13
Accessing the Swashplate Type Function .................................................................................................H-13
FUNCTION MODE.....................................................................................................................H-14
HELI – FUNCTION LIST............................................................................................................................H-14
D/R & EXP – DUAL RATE AND EXPONENTIAL ...............................................................................H-14
Auto Dual Rate..............................................................................................................................................H-15
REV.SW - SERVO REVERSING .................................................................................................................H-15
Sub Trim...........................................................................................................................................................H-16
TRVL ADJ. – TRAVEL ADJUST ................................................................................................................... H-17
Swash Mix- CCPM SWASHPLATE Mixing .............................................................................................H-18
Variations of CCPM Mixing ....................................................................................................................H-18
CCPM Servo Connection/Channel Numbers.................................................................................... H-18
Accessing the Swashplate Mixing Function.........................................................................................H-19
CCPM Exponential (EXP) ...........................................................................................................................H-19
THRO HOLD- THROTTLE HOLD..........................................................................................................H-20
Accessing the Throttle Hold Function .................................................................................................H-20
Stick Auto/Auto Cut Setting.......................................................................................................................H-21
Hold Delay......................................................................................................................................................H-21
THRO CURV – THROTTLE CURVES......................................................................................................H-22
Accessing the Throttle Curve Function...............................................................................................H-23
Throttle Trim Lever Function.....................................................................................................................H-24
Hovering Throttle Lever..............................................................................................................................H-24
Throttle Curve Exponential .......................................................................................................................H-24
Accessing the Throttle Curve Exponential Function........................................................................H-24
PIT. CURV/PITCH CURVES Function.......................................................................................................H-25
Accessing the Pitch Curve Function.....................................................................................................H-25
Hovering Pitch Lever....................................................................................................................................H-26
Example of Throttle Curve and Pitch Curve Settings ...................................................................... H-26
Accessing the Revolution Mixing Function .........................................................................................H-27
Setting up Revolution Mixing..................................................................................................................H-27
REVO.MIX/Revo Mix Function: Non Heading Lock Gyros Only.......................................................H-27
GYRO SENS/Gyro Gain Function.............................................................................................................H-28
Accessing the Gyro Gain Function .......................................................................................................H-28
Gyro Remote Gain Connections: JR G500T, JR770 and Others................................................... H-29
Remote Gain Gyros .....................................................................................................................................H-29
Mixing – Cyclic-to-Throttle Mixing........................................................................................................... H-29
Rudder-to-Throttle Mixing .........................................................................................................................H-30
Accessing the Cyclic-to-Throttle Function.........................................................................................H-31

Table of Contents
G-6
Aileron-to-Throttle and Elevator-to-Throttle Mixing...........................................................................H-31
Setting the Desired Flight Modes for Cyclic-to-Throttle Mixing...................................................H-31
GOVERNOR- GOVERNOR FUNCTION .............................................................................................H-32
Accessing the Governor Function ........................................................................................................H-32
PROG MIX 1-6 – PROGRAMMABLE MIXES 1 through 6..................................................................H-33
Swashplate Timing Mixes Example: Elevator-to-Aileron (Corrects Vertical Tracking)....................H-35
Swashplate Timing:Aileron-to-Elevator (Corrects Rolling Maneuvers)............................................H-37
STANDARD PROGRAMMABLE MIXES – Example: Right Aileron with Positive Pitch............H-39
MULTI-POINT MIXES – Example: FMOD to Gear Mixing (Retract and other Functions)......... H-41
Trainer – Programmable Trainer System..................................................................................................H-44
X9303 2.4 USED AS MASTER (INSTRUCTOR) – (Trainer System)............................................ H-44
X9303 2.4 USED AS SLAVE (STUDENT) – (Trainer System)........................................................H-45
Timer – Timer System .................................................................................................................................H-46
MONITOR- SERVO MONITOR ...............................................................................................................H-47
Setup Sheet (Helicopter).............................................................................................................................H-48
Sailplane – GLID Mode...................................................................................................................S-1
SYSTEM MODE GLID FEATURES ...........................................................................................................S-1
FUNCTION MODE GLID FEATURES ...................................................................................................S-1
System Mode......................................................................................................................................................S-2
System Mode......................................................................................................................................................S-2
To enter System Mode:................................................................................................................................S-2
Model Select.......................................................................................................................................................S-3
Copy – Copying the Currently Selected Model to Another Model Memory.....................................S-4
Model Name ......................................................................................................................................................S-6
Type Select..........................................................................................................................................................S-6
Model Reset .......................................................................................................................................................S-7
TRANSFER – Transfer the Model to Another Transmitter or to DataSafe .........................................S-8
TRANSFER a model from the X9303 2.4 – (Transfer function)............................................................S-8
TRANSFER a model to the X9303 2.4 – (Transfer function).................................................................S-9
Trim Step.......................................................................................................................................................... S-10
Device Select................................................................................................................................................... S-11
Flight Modes................................................................................................................................................ S-11
Activating and Assigning Flight Modes....................................................................................................... S-12
Motor Function .............................................................................................................................................. S-13
Flap and AUX Functions............................................................................................................................... S-14
Activating / Inhibiting Channels .............................................................................................................. S-14
Wing Type ........................................................................................................................................................ S-15
Function Mode ........................................................................................................................................... S-16
D/R & EXP – DUAL RATE AND EXPONENTIAL ................................................................................ S-18
REV.SW – SERVO REVERSING ................................................................................................................. S-19
SUB TRIM......................................................................................................................................................... S-20
TRVL.ADJ - TRAVEL ADJUST..................................................................................................................... S-21
Elevator-to-Flap Mix ...................................................................................................................................... S-21
Aileron-to-Flap Mix ....................................................................................................................................... S-22
Differential....................................................................................................................................................... S-22

Table of Contents
G-7
Camber Adjust................................................................................................................................................ S-23
Camber Mix .................................................................................................................................................... S-24
Aileron-to-Rudder Mix................................................................................................................................. S-25
Buttery Mix (Landing Flaps)....................................................................................................................... S-26
Flap Rate........................................................................................................................................................... S-27
Motor Hold ..................................................................................................................................................... S-27
Programmable Curve Mix 1 (Programmed for Spoiler-to-Elevator Mix).......................................... S-28
PROG MIX - PROGRAMMABLE MIXERS............................................................................................... S-29
MULTI-POINT PROGRAMMABLE MIXER ............................................................................................. S-33
Trainer – Programmable Trainer System................................................................................................... S-36
X9303 2.4 USED AS MASTER (INSTRUCTOR) – (Trainer System)............................................. S-36
X9303 2.4 USED AS SLAVE (STUDENT) – (Trainer System)......................................................... S-37
Timer ................................................................................................................................................................ S-37
Monitor ............................................................................................................................................................ S-38
Programming a 6-Channel Sailplane by Engineering Manager John Adams......................S-39
Channel Assignment .................................................................................................................................. S-41
Step #1 Servo Assignment .......................................................................................................................... S-41
Step #2- System Mode.................................................................................................................................. S-42
Step #3 Selecting a Model Memory........................................................................................................... S-42
Step #4 Selecting Model Type...................................................................................................................... S-43
Step #5 Naming a Model.............................................................................................................................. S-43
Step #6 Turning Off the Spoiler Stick Trim............................................................................................... S-44
Step #7 Establishing Flight Modes .............................................................................................................. S-44
Step #8 Wing and Tail Type Select .............................................................................................................. S-45
Step #9 Entering FUNC.LIST...................................................................................................................... S-45
Step #10 Servo Reversing............................................................................................................................ S-46
Step #11 Sub Trim.......................................................................................................................................... S-47
Step #12 Travel Adjust................................................................................................................................... S-48
Step #13 Buttery (Landing Flaps)............................................................................................................. S-48
Setting-up Flight Modes............................................................................................................................ S-49
Launch Mode Setup................................................................................................................................... S-49
Step #14 Spoiler to Elevator Curve Mix (Programmable Mix 1) ....................................................... S-49
Step #15 Launch Pre-sets ............................................................................................................................ S-50
Step #16 Dual Rate and Exponential......................................................................................................... S-51
Step #17 Elevator-to-Flap Mix .................................................................................................................... S-51
Step #18 Aileron-to-Flap .............................................................................................................................. S-52
Step #19 Aileron Differential....................................................................................................................... S-52
Flaperon Mix ............................................................................................................................................... S-53
Step #20 Flap Rate, Camber Mix and Camber Adjust........................................................................... S-53
Step #21 Flap Rate, Camber Mix and Camber Adjust (continued) .................................................... S-54
Flaperon Mix ............................................................................................................................................... S-54
Flaperon Mix Delay.................................................................................................................................... S-54
Setting up Cruise Mode............................................................................................................................ S-55
Step #22- Aileron-to-Rudder Mix ............................................................................................................. S-55
Step #23 Cruise Pre-sets ............................................................................................................................. S-56

G-8
Step #24 Dual Rate and Exponential......................................................................................................... S-56
Step #25 Elevator-to-Flap Mix .................................................................................................................... S-57
Step #26 Aileron-to-Flap .............................................................................................................................. S-58
Step #27 Aileron Differential....................................................................................................................... S-58
Flap Rate ...................................................................................................................................................... S-59
Flaperon Mix ............................................................................................................................................... S-59
Step #28 Flap Rate, Camber Mix and Camber Adjust........................................................................... S-59
Step #29 Flap Rate, Camber Mix and Camber Adjust (continued) .................................................... S-60
Flaperon Mix Delay.................................................................................................................................... S-60
Setting Up Land Mode .............................................................................................................................. S-61
Step #30 Aileron-to-Rudder Mix .............................................................................................................. S-61
Step #31 Land Pre-sets................................................................................................................................. S-62
Step #32 Dual Rate and Exponential......................................................................................................... S-63
Step #33 Elevator-to-Flap Mix .................................................................................................................... S-64
Step #34 Aileron-to-Flap .............................................................................................................................. S-64
Step #35 Aileron Differential....................................................................................................................... S-64
Flaperon Mix ............................................................................................................................................... S-65
Flaperon Mix ............................................................................................................................................... S-65
Step #36 Flap Rate, Camber Mix and Camber Adjust........................................................................... S-65
Step #37 Flap Rate, Camber Mix and Camber Adjust (continued) .................................................... S-66
Step #38 Aileron-to-Rudder Mix .............................................................................................................. S-66
Flaperon Mix Delay.................................................................................................................................... S-66
Setup Sheet (Sailplane).................................................................................................................................. S-67
Servo Precautions.......................................................................................................................................... W-1
General notes ................................................................................................................................................. W-1
Federal Aviation Administration.................................................................................................................. W-2
1. Purpose .................................................................................................................................................... W-2
2. Background.............................................................................................................................................. W-2
3. Operating Standards ............................................................................................................................. W-2
Warning........................................................................................................................................................ W-3
Warranty Period ........................................................................................................................................ W-3
Limited Warranty ....................................................................................................................................... W-3
Damage Limits ............................................................................................................................................ W-3
Safety Precautions...................................................................................................................................... W-3
Questions,Assistance, and Repairs ........................................................................................................ W- 3
Warranty and Service Information ............................................................................................................ W-3
Warranty and Service Information ............................................................................................................ W-4
Inspection or Repairs................................................................................................................................ W- 4
Warranty Inspection and Repairs........................................................................................................... W-4
Non-Warranty Repairs............................................................................................................................. W-4
Safety, Precautions, and Warnings........................................................................................................... W-4
Instructions for Disposal of WEEE by Users in the European Union............................................ W-5
FCC Information........................................................................................................................................ W-5

JR X9303 Transmitter
Section 2: Transmitter and Receiver Specifications
Section 1: Using the Manual
G-9
JR’s X9303 2.4 offers airplane, helicopter and sailplane
pilots sophisticated programming that JR’s 9303 is
famous for with the added benefits of fully integrated
Spektrum 2.4GHz DSM®radio link technology. DSM
(Digital Spektrum Modulation) technology offers a far
superior RF link than narrow band 72MHz FM and PCM
systems, providing a higher level of confidence and
safety. Now with even the most sophisticated models
up to 9 channels, you’ll no longer have to wait for an
open frequency, worry about someone unintentionally
powering up on the same frequency, or have to plan a
frequency-based flight matrix for competition. And for
response-critical aircraft like 3D helicopters and airplanes,
latency (the time it takes for a stick input to translate to a
servo output) is significantly reduced providing a more
responsive precise connection to your model.
Features
• Fully integrated 2.4GHz Spektrum RF link
• Sophisticated three-model-type programming: Airplane, Helicopter, Sailplane
• Patented DuaLink™Technology
• ModelMatch™
• ServoSync™
• Rolling Selector input
• Digital 3+1 trims
• 30-model memory
Specifications
• Model number—Airplane/Sailplane (JRP2910), Helicopter (JRP2920)
• Number of channels—9
• Modulation type—Direct Sequence Spread Spectrum DSM2/ DSM1 protocol
• Band—2.400 to 2.483GHz
• Spectral capacity—40 simultaneous systems
• Transmitter Current—180mA/DSM2 280mA/ DSM1
• Resolution—2048 w/R921 receiver
In the front of this manual you will find common
transmitter features and specifications plus information
on the included components and accessories. Guidelines
for receiver and servo installation are also included. In
each section of this manual (Air, Heli and Sailplane) are
instructions for adjusting model-specific programming
and functions. An explanation of the purpose of each
programming function is provided, followed by an
illustration of its corresponding LCD display and
instructions on how to access and adjust the function.
A blank data sheet has been included at the end of
each section, as well as on the JR web site. Once all
data has been input for a particular model, it is highly
recommended that you record these values and settings
on a copy of the data sheet, so in the rare event of a loss
of memory, these settings are available.
Note: The manual for the X9303 2.4 manual is posted
online at www.horizonhobby.com in the support section or
it can be ordered from your local hobby dealer or directly
from Horizon Hobby.

JR R921 Receiver
G-10
The R921 receiver combines two internal with one or
two (optional) remote receivers, offering superior path
diversity. The radio system simultaneously transmits
on two frequencies, creating up to four RF paths on two
different 2.4GHz channels. This multi path redundancy,
plus the fact that each of the up to 4 receivers are located
in different locations throughout the aircraft exposes each
to a different RF environment creating a superior RF
link in all conditions. The JR R921 allows the use
of an optional Flight Log Data Recorder (SPM5940) to
be used. The flight log plugs into the data port and
provides quality of RF link data of the previous flight
allowing the confirmation of the operational performance
of the systems.
Features
• 9 channels
• 2 internal receivers
• 1 or 2 (optional) remote receiver(s)
• Patented multi-link technology
• Two types of fail-safe—SmartSafe and Preprogrammed fail-safe
• Flight Log compatible
Specifications
• Number of Channels—9
• Modulation—DSM2
• Band—2.400 to 2.4835GHz
• Dimensions (WxLxH)—.35”x2.06”x0.55”
• Weight—Main 15g/.6oz Remote 3g/.2 oz each
• Current—70mA
• Voltage range—3.5 to 9.6V
Note: The X9303 2.4 is compatible with all current Spektrum DSM aircraft receivers including:
AR6000 6-channel parkflyer receiver
AR6100 6-channel 3.5-gram parkflyer receiver
AR6200 6-channel full-range receiver
AR7000 7-channel full-range receiver
AR9000 9-channel full-range receiver
Important: When using the X9303 2.4 with parkflyer receivers (the AR6000 and AR6100), it’s imperative that these
receivers only be flown in parkflyer-type aircraft (small electric airplanes or mini and micro helicopters). Flying
receivers designed for parkflyers in larger aircraft could cause loss of control.

Servo Specifications
Section 3: Component Specifications
Charger Specifications
G-11
Type DS821
Torque 72 oz/in
Speed .19
Weight 1.5 oz
Size (in) (L x W x H) .74x1.50x1.47
Ball Bearing Yes
Motor 3-pole Ferrite
Model Number AD35M05
Input Voltage AC 120V, 60Hz
Output Current 11.6V Tx/110mAh, 5.8V Rx/110mAh
Charging Time 15 hours
Airborne Battery Pack
Airborne Battery Pack Specifications
Model Number B1100
Voltage 4.8V
Size (in) (L x W x H) 2.24 x 0.63 x 1.70
Weight (oz) 4.9

Transmitter/Receiver
Battery Charging
G-12
Note: It is imperative that you fully charge both the
transmitter and the receiver battery packs prior to
each flying session and that you check the condition
of the receiver battery between each flight using
a reliable battery tester with a built-in load. The
included wall charger slow charges at a 110mA rate.
In order to fully charge the included batteries, it’s
necessary to leave the charger and batteries hooked
up to the included wall charger for 15 hours.
An optional fast charger can be used to charge both the
transmitter and receiver batteries, however, it’s imperative
that the batteries are properly charged and the charge
condition be checked prior to flight. False peaking is a
common occurrence with many fast chargers (batteries
giving an indication the battery is fully charged when
in fact the battery is only partially charged). False
peaking can lead to disastrous results and it is the
pilot’s responsibility to verify the charge condition of the
batteries before every flight. (Also see Receiver Power
Requirements page G-24)
JR Transmitter Charging
The center pin on all JR® and Spektrum™transmitters is
negative. Therefore, the center pin on all JR chargers is
negative, not positive. This is different from many other
manufacturers’ chargers and radio systems. Beware of
improper connections based on “color-coded” wire leads,
as they may not apply in this instance. You must make
sure that the center pin of your JR transmitter is always
connected to the negative pole for correct polarity.
Note: When using a fast charger to charge the
transmitter battery do not exceed 1.5 amps (or
1500mAh) charge rate or damage to the transmitter
or battery damage can occur.
Using the Included Charger
The pilot lamps should always be on during the charging
operation. If not, check to make sure that both the
transmitter and receiver are switched off.
Do not use the charger for equipment other than JR. The
charging plug polarity may not be the same. Equipment
damage can result.
Do not use other manufacturers’ after-market accessories
that plug into the transmitter’s charging jack if you are
unsure of the polarity compatibility with your radio. Seek
expert advice to avoid possible damage.
During the charging operation, the charger’s temperature
is slightly elevated.
CENTER
PIN IS
NEGATIVE
OUTSIDE IS POSITIVE
CHARGER PIGTAIL FOR RECEIVER
CHARGER PIGTAIL FOR TRANSMITTER
BLACK TO POSITIVE
RED TO NEGATIVE
RIGHT SIDE OF TRANSMITTER
RED–POSITIVE / BROWN–NEGATIVE / ORANGE–SIGNAL

X9303 2.4 Transmitter Features (Mode 2 Airplane Shown)
G-13
Trainer Button
Gear Switch
Flap Switch
Elevator
Dual Rate
Flap Trim
Lever
AUX4/
Rudder Dual
Rate
Aux Trim
Aileron
Dual Rate
AUX2
Mix Switch
Lever
Elevator/
Aileron Stick
Throttle/
Rudder Stick
Rudder Trim
Throttle Trim
List Button
Enter Button
Clear Button
Power Switch
Aileron Trim
Elevator Trim
Rolling Selector
LCD Display

X9303 2.4 Transmitter Features (Rear)
G-14
Model No. X9303
FCC ID: BRWDAMTX10
IC: 6157 A-BRWDAMT
HORIZON HOBBY, INC. MADE IN JAPAN
Battery Cover
CAUTION: THE BATTERY CONNECTION IS KEYED SO THAT IT CAN ONLY
BE PLUGGED IN ONE DIRECTION. DO NOT FORCE.

X9303 2.4 Transmitter Features (Internal)
Control Stick Tension Adjustment
G-15
Remove the six transmitter screws from the back cover as
shown on page G-14. Remove the transmitter back, being
careful not to cause damage to any components.
Adjust each gimbal tension screw for desired tension
(counter-clockwise to loosen stick tension; clockwise to
tighten stick tension). When adjusting the throttle ratchet
tension, make sure that the adjusting screw does not
touch the PC board after adjustment is complete.
Back of Transmitter (Mode 2)
THROTTLE TENSION SCREW
RUDDER TENSION SCREW
ELEVATOR TENSION SCREW
AILERON TENSION SCREW

Control Stick Length
Neckstrap Attachment
G-16
Advanced Digital Trims
The X9303 2.4 features Advanced digital trims. On the
Normal display screen, if a trim lever is moved, the screen
will automatically change to display the graphic position
for the trim being adjusted. The X9303 2.4’s Aileron,
Elevator, and Rudder trim levers feature an audible center
trim beep. This is helpful in determining the trim levers’
center position during flight. In addition, the frequency of
each trim step changes from full right/up to full left/down,
allowing the pilot to be aware of the general trim position
audibly without looking at the transmitter.
By using the Trim Step Function located in the System
Mode, the amount of travel per each trim step can be
adjusted as needed to match your specific application.
Please note that when the X9303 2.4 transmitter is turned
off, the trim values are stored in memory and are recalled
when the system is turned back on.
Use a 2mm Allen wrench to unlock the setscrew to adjust
the stick length. Turn the wrench counterclockwise to
loosen the screw. Then, turn the stick clockwise to shorten
or counterclockwise to lengthen the overall stick length.
After the control stick length has been adjusted to suit your
flying style, tighten the 2mm setscrew. If you desire longer
sticks, JR® offers a stick (JRPA047) that is approximately
one inch longer than standard, and has various length
anodized aluminum stick ends available (JRPA040-
JRPA045). These stick ends are crafted from bar stock
aluminum, and are available at your local JR dealer.
An eyelet is provided on the face of the X9303 2.4 transmitter
that allows you to connect a Neck Strap (JRPA023).
LOOSEN
TIGHTEN
SETSCREW

Installing the Receiver
G-17
Installing the JR R921
The JR R921 incorporates dual internal receivers, and one
or two remote receivers offering the security of up to four
simultaneous RF links for the ultimate in multi-path RF
security. Two internal receivers are located on the main
PC board, while a third remote receiver must be plugged
into one of the antenna ports in order for the system to
operate. Optionally, a second remote receiver can be
plugged into the remaining remote antenna port giving
a total of four operational receivers. By locating these
receivers in different locations throughout the aircraft,
each receiver is exposed to its own RF environment,
greatly improving path diversity (the ability of the receiver
to see the signal in all conditions).
Note: The JR R921 requires that at least one remote
receiver be used.
Install the main receiver using the same method you
would use to install a conventional receiver in your
aircraft. Typically wrap the main receiver in protective
foam and fasten it in place using rubber bands or Velcro
straps. Alternately in electric models or in jets (low
vibration), it’s acceptable to use thick double-sided foam
tape to fasten the main receiver in place.
Mounting the remote receiver(s) in a different
location(s), from the primary receiver, gives tremendous
improvements in path diversity. Essentially each receiver
sees a different RF environment and this is the key to
maintaining a solid RF link, even in aircraft that have
substantial conductive materials, (i.e. Turbine engines
with metal tail pipes, carbon fiber, tuned pipes, etc.) which
can attenuate the signal.
Using double-sided foam tape, (servo tape) mount the
remote receiver(s) keeping the remote antenna(s) at least
2 inches away from the primary antenna. Ideally the
antennas will be oriented perpendicular to each other;
however, we’ve found this to not be critical. 6-inch,
9-inch, 12-inch, 24-inch and 36-inch leads are available
and in sophisticated aircraft, we’ve found it best to mount
the remote receivers in different parts of the aircraft
keeping the remote antennas as far away as practical from
any conductive materials. A typical installation would
include the main receiver mounted in the conventional
location in the fuselage and the remote antennas in the
nose (jets) in the top turtle deck and even in the tail. The
optimum location is as far away from any conductive
materials as practical.

G-18
In helicopters, there is generally enough room on
the servo tray to achieve the necessary separation. If
necessary, a mount can be made using clear plastic to
mount the external antenna as shown below.
Other Important Installation Tips
1. The servos should be mounted using rubber grommets
and brass eyelets to isolate them from vibration. Do
not over-tighten the mounting screws; this will negate
the vibration absorption effect of the rubber grommets.
The following diagram will assist you in properly
mounting your servo.
The brass eyelets are pushed from the bottom up in the
rubber grommets. When the servo screw is tightened
securely, it provides the proper security as well as the
proper vibration isolation for your servo.
2. The servos must be able to move freely over their
entire range of travel. Make sure that the control
linkages do not bind or impede the movement of any
of the servos.
3. Mount all switches away from the engine exhaust and
away from any high vibration areas. Make sure the
switch operates freely and is able to operate over its
full travel.
Model Match
The X9303 2.4 features patented ModelMatch technology
that prevents the operation of a model if the wrong model
memory is selected. During binding, the receiver actually
learns and remembers the specific model memory (1 thru
30) that the transmitter is currently programmed to. Later if
the incorrect model memory in the transmitter is selected
and the receiver is turned on, the model simply won’t
operate, preventing a possible crash. Change programming
to the correct model memory and you’re set to fly.
Servo Mounting Tab
Screw
Rubber Grommet
Brass Eyelet

G-19
It’s necessary to program the receiver to the transmitter
so that the receiver will only recognize that specific
transmitter, ignoring signals from any other sources. If the
receiver is not bound to the transmitter, the system will
not operate. During binding, the servo’s fail-safe positions
are stored.
The following sequence describes the binding procedure
for the JR R921, however, all JR and Spektrum DSM
aircraft receivers are bound in the same way.
How To Bind
1. With the system hooked up as shown, insert the bind
plug in the charge plug receptacle. The switch must be
a 3-wire type switch (JRPA001 or JRPA004) to enter
the bind mode through the switch. If a 3-wire switch is
not available, install the male bind plug into the charge
plug receptacle and power the receiver through any
other open port to enter bind mode.
REMOVE BEFORE USE
2. Turn on the receiver switch. Note that the LED’s on
all receivers should be flashing, indicating that the
receiver is ready to bind.
AR9000
3. Establish the desired fail-safe stick positions: normally
low throttle and flight controls neutral.
4. Press and hold the bind button on the back of the
transmitter while turning on the power switch. The
bind button should flash and within a few seconds the
system should connect. The LED’s on the receivers
should go solid, indicating the system has connected.
5. Remove the bind plug from the receiver or switch
harness and store it in a convenient place.
6. After you’ve programmed your model, it’s important to
rebind the system so the true low throttle and neutral
control surface positions are programmed.
Note: To bind an aircraft with an electronic speed
controller that powers the receiver through the
throttle channel (BEC), insert the bind plug into the
battery port and proceed to Step #2.
Binding

G-20
The JR R921 receiver features two types of fail-safe:
SmartSafe and Preset Fail-safe.
SmartSafe
This type of fail-safe is especially ideal for most types of
electric aircraft and is also recommended for most types
of gas- and glow-powered airplanes and helicopters.
Here’s how SmartSafe works.
Receiver Power Only
When the receiver only is turned on (no transmitter signal
is present), all servos except for the throttle are driven to
their preset fail-safe positions, normally control surfaces
at neutral and the landing gear down. These fail-safe
positions are stored in the receiver during binding. At this
time the throttle channel has no output, to avoid operating
or arming the electronic speed control. In glow-powered
models, the throttle servo has no input so it remains in its
current position.
After Connection
When the transmitter is turned on and after the receiver
connects to the transmitter, normal control of all channels
occurs. After the system makes a connection, if loss of
signal occurs, SmartSafe drives the throttle servo only
to its preset fail-safe position (low throttle) that was set
during binding. All other channels hold their last position.
When the signal is regained, the system immediately (less
than 4 ms) regains control.
Preset Fail-Safe
Preset fail-safe is ideal for sailplanes and is preferred by
some modelers for their glow- and gas-powered aircraft.
Receiver Power Only
When the receiver only is turned on (no transmitter signal
is present) all servos except for the throttle are driven to
their preset fail-safe positions, normally control surfaces
at neutral and the landing gear down. These fail-safe
positions are stored in the receiver during binding. At this
time the throttle channel has no output, to avoid operating
or arming the electronic speed control. In glow-powered
models, the throttle servo has no input so it remains in its
current position.
After Connection
When the transmitter is turned on and after the receiver
connects to the transmitter, normal control of all
channels occurs. After the system makes a connection,
if loss of signal occurs preset fail-safe drives all servos
to their preset fail-safe positions. For sailplanes,
it’s recommended that the spoilers/flaps deploy to
de-thermalize the aircraft, preventing a flyaway. Some
powered modelers prefer to use this fail-safe system to
program a slight turn and low throttle to prevent their
aircraft from flying away. When the signal is regained, the
system immediately (in less than 4 ms regains control).
Programming SmartSafe
(All Spektrum Aircraft Receivers)
During the binding process the bind plug is left in
throughout the process and is removed only after the
receiver connects to the transmitter. After the connection
is made, confirmed by operating the servos, the bind plug
can be removed. The receiver is now programmed for
SmartSafe.
Fail-Safe Functions