Horizon Hobby XR2i User manual

XR2i
2-Channel, 2-Model Memory
AM Computer Racing System
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Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . .
XR2i Quick Start Setup . . . . . . . . . . .
Direct Trim Access . . . . . . . . . . . . . .
Servo Trim Adjustment . . . . . . . . .
System Features . . . . . . . . . . . . . . . . .
Transmitter . . . . . . . . . . . . . . . . . . .
Receiver . . . . . . . . . . . . . . . . . . . . . .
Servos . . . . . . . . . . . . . . . . . . . . . . .
System Specifications . . . . . . . . . . .
Components . . . . . . . . . . . . . . . . . .
Transmitter . . . . . . . . . . . . . . . . . . .
Receiver . . . . . . . . . . . . . . . . . . . . . .
Servos . . . . . . . . . . . . . . . . . . . . . . .
Control Identification
and Location . . . . . . . . . . . . . . . . . . . .
R/C Safety Precautions . . . . . . . . . . .
Steering Tension Adjustment . . . . .
Charging Jack . . . . . . . . . . . . . . . . . .
Receiver/Servo Connections
and Installation . . . . . . . . . . . . . . . . .
Operating Your Model . . . . . . . . . .
Servo Layout . . . . . . . . . . . . . . . . . .
Key Input and Display . . . . . . . . . . .
Display Screens . . . . . . . . . . . . . . . .
Normal Display . . . . . . . . . . . . . .
Low-Battery . . . . . . . . . . . . . . . . .
Lithium Battery . . . . . . . . . . . . . . .
Memory Backup . . . . . . . . . . . . .
Accessing the System Mode . . . .
Model Select . . . . . . . . . . . . . . . .
Model Name Entry . . . . . . . . . . .
Grip Button C Function Select
Data Reset . . . . . . . . . . . . . . . . . . .
Accessing the Function Mode . . .
End-Point Adjustment . . . . . . . .
Sub-Trim . . . . . . . . . . . . . . . . . . .

Servo Reversing . . . . . . . . . . . . .
Accessing the Direct Trim Mode
Steering Trim . . . . . . . . . . . . . . . .
Throttle Trim . . . . . . . . . . . . . . . . .
Grip Lever B: Steering Dual-Rate
Trim Adjustment STG . . . . . . . . .
Grip Lever A: Brake Endpoint
Adjustment BRK . . . . . . . . . . . . .
XR2i Data Sheets . . . . . . . . . . . . . . .
Frequency Chart . . . . . . . . . . . . . . .
Warranty and Service Information
Introduction
Thank you for purchasing the XR2i 2-channel radio system. This system has
been designed to provide R/C racers with a high quality, user-friendly radio
system that can be relied upon year after year, race after race. It is important that
you carefully read this manual before attempting to operate your XR2i system.
For your convenience, a blank data sheet has been included in the back of this
manual. Once you have input all the necessary data for a particular model into
your transmitter, we strongly recommend that you immediately write that
information down on the data sheet provided. This will insure that in the rare case
of a memory failure, you will not lose the models' setup data.
For those who would like to get out to the track quickly with just the basic radio
setup, please refer to the Quick Start section that follows.
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XR2i Quick Start Setup
Included in this manual are in-depth instructions detailing all the steps and
procedures needed to correctly program each of the XR2i's features. Quick Start
covers the basic programming information necessary to get you to the track fast.
Later, when you want to learn more about the specific features of the XR2i, refer
to the appropriate page(s) in this manual for more detailed programming
information.
Servo Reversing
1. With the transmitter power switch on, press the Scroll key to enter the Function
mode.
2. Press the Scroll key until "REV.NORM" appears on the screen. The "ST"
indicates the steering servo reversing screen.

3. Press the Increase or Decrease key to move the cursor to the desired servo
direction (Rev.Norm).
4. Press the Channel key once to access the throttle servo reversing screen.
5. To select the direction of the throttle servo, repeat Step 3 above.
End-Point (Travel) Adjustment
1. From the Servo Reverse function, press the Scroll key once to access the
End-Point (Travel) Adjustment function (the EPA screen with "ST" will appear).
Steering Adjustment
2. Rotate the steering wheel in the desired direction (left or right) to be adjusted.
3. Press the Increase or Decrease keys to select the desired travel value.
Throttle Adjustment
4. Press the Channel key once. "TH" will appear on the screen.
5. Pull the trigger for foward or push the trigger for brake adjustment.
6. Press the Increase or Decrease keys to select the desired travel value.
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Direct Trim Access
Servo Trim Adjustment Steering
1. With the transmitter power switch on, move the digital steering trim lever in the
desired position to be adjusted.
The steering trim value screen will appear automatically.
Throttle
2. With the transmitter power switch on, move the digital throttle trim lever in the desired
position to be adjusted.
The throttle trim value screen will appear automatically.
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System Features
Transmitter
• 2 channels
• AM modulation
• Easy-to-read LCD graphics display
• 2-model memory
• 3-character model name entry
• Electronic digital trim levers for throttle and steering
• Assignable electronic grip lever
• Direct display trim function
• Servo reversing
• Sub-trim
• Steering dual-rate

• Steering end-point adjustment (two points: left and right)
• Brake/throttle endpoint adjustment
• Low-battery alarm
• Plug-in crystals
• Charge jack receptacle (rechargeable batteries not included; order JRPB958)
R-125 Receiver
• 2 channels
• AM modulation
• 27MHz/75MHz available
• Battery Eliminator Circuitry (BEC)
• Patented ABC&W interference technology
Z590M Servo
• Metal gears for durability
• Great high torque car/buggy steering servo
• Indirect drive feedback potentiometer for additional vibration protection
• Surface Mount Technology (SMT)
Z270 Servo
• Low current drain
• Indirect drive feedback potentiometer for additional vibration protection
• Surface Mount Technology (SMT)
• Durable nylon gear train
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System Specifications
Components
Transmitter XR2i
Receiver R-125
Servos Z590M x 1
Z270 x 1
Accessories BEC switch harness with battery case, servo accessories (for each servo),
instruction manual
XR2i Transmitter
Model number XR2i
Encoder 2-channel computer system
RF output 27MHz/75MHz
Modulation AM
Output power 195mW
Current Drain 150mA

Power source 1.5V x 8 dry cell
(1.2V x 8 Ni-Cd optional)
Output pulse 1000–2000 (1500 neutral)
R-125 Receiver
Model number NER-125
Type 2-channel/AM
ABC&W circuitry
Frequency 27MHz/75MHz
Sensitivity 5qs minimum
(microseconds)
Selectivity 8 KHz/50dB
Weight 1 oz
Size (WxLxH) 1.25" x 1.75" x 0.81"
Receiver Antenna 20"
Power supply 4.8–6.0V DC
Z270 Servo
Torque 49 ounce inch (@6.0V)
Speed .19 sec/60° (@6.0V)
Weight 1.50 oz
Size (WxLxH) 0.73" x 1.51" x 1.37"
Motor 3-pole ferrite
Z590M Servo
Torque 85 ounce inch (@6.0V)
Speed .15 sec/60° (@6.0V)
Weight 1.6 oz
Size (WxLxH) 0.73" x 1.55" x .146"
Motor 3-pole ferrite
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Control Identification and Location
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Antenna
Steering Wheel Electronic Digital
Throttle Trim Lever Dot Matrix
Multi- Data
LCD Display
Three-Character
Name Input
Digital Voltage
Reading
Electronic Digital

Grip Lever A
Electronic Digital
Grip Lever B
Grip Button C
Charge Jack
Power Switch
Scroll Button
= Enter Function
= Clear Function
Channel Button
Increase Button
Decrease Button
Electronic Digital
Steering Trim Lever
Throttle Trigger Adjustable
Steering Tension
Battery Cover *
(8 "AA" batteries required)
*To remove battery cover, press down on the arrow and push the cover in the direction of the arrow. Remove the battery
case and install 8 "AA" batteries in the direction shown as molded into the battery case. If transmitter voltage fails to
register, check for correct battery installation and voltage.
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R/C Safety Precautions
For safe and reliable performance of your R/C model, please carefully read and follow
the guidelines below.
1. Radio control models are not toys. They are capable of inflicting serious injury to
people and property. Use caution at all times when operating your model.
2. You are responsible for the safe operation of your R/C model. You must properly
install, test and operate your model with a clear sense of that responsibility. Do not
take risks that might endanger yourself or others.
3. Running an R/C car in the streets is very dangerous to both drivers and models. Avoid
running your model in areas occupied by full-size automobiles. To locate areas where
you can safely operate your model, contact your local hobby shop for R/C tracks or clubs
in your area.
4. When running an R/C boat, keep it away from any swimmers, full-size boats and
wildlife. Also, watch carefully for fishing lines that may get tangled in the propeller.
5. Before operating your model, make sure your frequency is clear. If someone else is
operating on the same frequency, both models will go out of control, possibly causing
damage to the models, as well as others.
6. If at any time while operating your R/C model you sense abnormal model functioning,
end your operation immediately. Do not operate your model again until you are certain
the problem has been corrected.
Caution: Control of your model is impossible without sufficient voltage for the
transmitter and receiver. A weak transmitter battery will decrease your range of
operation, and a weak receiver battery will slow servo movement and decrease your
range of operation. Check your receiver pack voltage often to avoid losing control of
your model. When using a model that operates both the electric motor and the receiver
from the same battery (Battery Eliminating Circuitry or BEC), you should discontinue
use when the top speed sharply decreases or you'll quickly lose control of your model.

Transmitter Crystal Replacement Notice
The Federal Communications Commission (FCC) requires that changes in transmitter
frequency must be preformed only by an authorized service technician (Horizon Service
Center). Any transmitter frequency changes made by a non-certified technician may
result in a violation of the FCC rules.
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Steering Tension Adjustment
Steering tension is adjustable via the recessed screw located beneath the steering wheel
(see page _ for exact location). Turning the screw clockwise increases the steering
tension.
Charging Jack
Located on the left-hand side of the transmitter is the charging jack that accepts only JR
wall chargers. Please do not attempt to use any other brand of wall charger, as it may be
reverse polarity and can cause damage to your system. Only use the JR wall charger
when the XR2i is equipped with Ni-Cd batteries (JRPB958, available separately).
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Receiver/Servo Connections and Installation
Your R-125 receiver is equipped with Battery Eliminator Circuitry (BEC). The receiver
gets its power from the model’s Ni-Cd battery pack, thus saving the weight of an
additional receiver battery. Ni-Cd batteries from 4.8–8.4V (4–7 cells) can be used safely.
Higher voltage packs may damage the receiver and servos.
Note: When using a separate receiver Ni-Cd as a power source, the operating voltage
range is 4.8–6.0V (4- to 5-cell).
Attention: Make sure the male and female connectors have the correct polarity (+/-)
before connecting. The servo lead and receiver case are molded so that the lead can only
be inserted correctly. Be sure to orient the servo plug correctly for proper insertion.
You may use a separate receiver battery to power the receiver (such as for some electric
boats or in gas-powered vehicles). A Ni-Cd pack plugged into the battery socket on your
receiver will operate your receiver. You can also use alkaline batteries with the included
battery box.
If you use a mechanical speed controller, please make sure it has the correct connector for
a BEC system (red connector). See Figure A below for a typical setup. Most electronic
speed controllers are set up for BEC operation and plug directly into your receiver

(Figure B). See Figure B for a typical setup and check your speed controller‘s manual for
correct installation.
Figure A – Connections to BEC receiver with mechanical speed controller. Ni-Cd battery and speed controller are not included in the
radio set.
Figure B – Connections to BEC receiver with electronic speed controller. Ni-Cd battery and speed controller are not included in the
radio set.
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Operating Your Model
It’s important to learn the proper sequence for switching on/off your radio system.
Before Operation
Switch on the transmitter, then the receiver.
After Operation
Switch off the receiver, then the transmitter. This ensures that you will always have a
signal to the receiver and that your R/C model will not operate out of control when you
turn off the transmitter.
Servo Layout
Note: Rubber grommets and (sometimes) eyelets are used in fuel-powered vehicles.
Key Input and Display
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Display Screens
Normal Display
When the power switch is turned on, the LCD screen will read as shown below. This
screen is referred to as the Normal Display.
Note: If any of the electronic trim buttons are moved while in this screen, the screen will
automatically change to display the trim in use. This is called the Direct Trim mode. For
more information on the feature, please see page __ of this manual.
Low Battery/Lithium Battery Backup
When the voltage of the 8 "AA" batteries drops below 9.0V, the XR2i's display screen
will alternate between the Normal and Low-Battery screen (BAT), and a continuous
beeping will occur, indicating that the batteries need to be replaced before further use.
The Low-Battery screen is active during any operating modes.
Lithium Battery

Your XR2i radio system is equipped with a five-year lithium battery backup system. This
system is designed to protect and retain all radio programming in the event that the
transmitter batteries drop below the required 9.0 volts, or the transmitter battery case is
removed during battery changes. If after five years it becomes necessary to replace the
lithium battery, return your system to the Horizon Service Center for repair (see address,
page __).
Memory Backup
If the Memory Backup screen appears, this indicates the possibility of a ROM problem or
the lithium battery is dead. If you switch the power off and on again, but the transmitter
is in the default mode with all data lost, it is strongly suggested that the XR2i transmitter
be returned to the Horizon Service Center for servicing (see Warranty Information page
__).
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Accessing the System Mode
To enter the System mode, press both the Scroll and Channel keys at the same time while
turning on the transmitter power switch. By pressing the Scroll key, you can now choose
Model Select, Model Name Input, Grip button C function or the Data Reset function as
shown here on the System Mode flow chart. Information for each function is located on
the page number listed next to the function name on the flow chart.
To exit the System mode, press the Scroll and Channel keys at the same time or simply
turn off the transmitter.
Note: If you turn the transmitter off and immediately enter System mode again, you will
be returned to the last System mode function used instead of the model select function.
While in System mode, there is no RF output generated by the transmitter. Adjustments
can be performed with reduced battery power consumption. If you exit System mode by
pressing the Scroll and Channel key at the same time, RF output will not be enabled until
you first turn off the transmitter.
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Model Select
(System Mode)
The XR2i has memory for two models. This feature allows for two different models to be
operated with the same transmitter (additional receivers and servos must be purchased
separately) or one model with two different race setups.
Accessing the Model Select Function

1. Press the Scroll and Channel keys at the same time and hold.
2. Turn the transmitter power switch on to enter System mode.
3. If "MDL" does not appear on the screen, press the Scroll key until "MDL" appears.
4. Press the Increase or Decrease keys to select the desired model number (1 or 2).
5. Press the Scroll key to access the Model Name Entry function.
6. To exit System mode, either turn the transmitter power switch off or press the Scroll
and Channel keys at the same time.
Model Name Entry
(System Mode)
The XR2i allows a three-character name to be input for each of the two models available.
The current model with name will then be displayed in the Normal display screen. This
feature is useful to help identify different models, setups, etc.
Accessing the Model Name
Entry Function
1. Press the Scroll and Channel keys at the same time and hold.
2. Turn on the transmitter power switch to enter the System mode.
3. Press the Scroll key until "MD1" appears on the screen with the first character
flashing.
4. Press the Increase or Decrease keys to select the correct letter/number for the first
character (flashing).
5. To change the remaining two characters, press the Channel key until the desired
character to be changed is flashing.
6. Press the Scroll key to access the Grip Button C function.
7. To exit the System mode, either turn the transmitter power switch off or press the
Scroll and Channel keys at the same time.
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Grip Button C Function Select (System Mode)
The Grip Button C function of the XR2i allows you to select from 2 different functions
available. Use the information below to select the correct Grip Button C assignment for
your particular installation.
0 = The 0, or off function, is the default setting and does not assign a function to Grip
Button C.
Eb = The Eb or Emergency Steering Button function is designed to override the value of
Grip Dial B and provide 100% steering rate. This feature is useful if you have reduced
the steering rate to make your vehicle easier to drive but need full steering in an
emergency situation such as a collision.
Accessing the Grip Button C Function
1. Press the Scroll and Channel keys at the same time and hold.

2. Turn on the transmitter power switch to enter System mode.
3. Press the Scroll key until "GBC" appears on the screen.
4. Press the Increase or Decrease key to select the correct Grip Button C function type to
be used.
5. Press the Scroll key to access the Data Reset function.
6. To exit the System mode, either turn the transmitter power switch off or press the
Scroll and Channel keys at the same time.
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Data Reset (System Mode)
The Data Reset function allows you to reset all the programming in the selected model (1
or 2) to the factory default settings. Before using the Data Reset function, it is important
to enter the Model Select function and check to make sure the current model number
indicated (1 or 2) is the model to which you want to reset to the factory default settings.
The Model Select function is described on page __.
Accessing the Data Reset Function
1. Press the Scroll and Channel keys at the same time and hold.
2. Turn on the transmitter power switch to enter the System mode.
3. Press the Scroll key until "CLR" appears on the screen.
4. Press the Increase and Decrease keys at the same time to reset the data. To confirm that
the selected model's programming has been reset, a beep will sound and the model
number selected (1 or 2) will stop flashing.
5. Press the Scroll key to access the Copy Model Data function.
6. To exit the System mode, either turn the transmitter power switch off or press the
Scroll and Channel keys at the same time.
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Accessing the Function Mode
To enter the Function mode, it is necessary to first turn on the transmitter's power
switch. Next, press the Scroll key until a beep is heard. The display will change to
show the first function listed on the Function mode flow chart as shown below.
Press the Scroll key to scroll down through the functions one by one, as shown in
the flow chart. Once the desired function has been reached, use the Channel key
to select the appropriate channel (if applicable). To adjust the values of the
function, simply press the Increase (+) or Decrease (-) keys until the desired
value is displayed on the screen. To exit function mode, press the Scroll and
Channel keys at the same time. The next time you enter Function mode, you will
be returned to the last function accessed.
{Insert Function Mode flow Chart}
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End-Point Adjustment (Function Mode)
The End-Point Adjustment feature of the XR2i allows the maximum travel of both the
steering and throttle servos to be increased or decreased in each direction to achieve the
exact servo movement needed. The End-Point Adjustment range is from 0% to 125% and
is factory set to 100% for both channels. The value displayed on the screen depends on
the current position of the steering wheel, trigger, or trim lever to be adjusted. This
feature is very useful either to maximize servo travel or to reduce servo over-travel to
eliminate servo binding (servo moves further than control mechanism allows), without
the need for mechanical linkage adjustment.
The screens below are accessed by turning the wheel to the desired direction to be
adjusted (left or right), by moving the trigger to the forward or backward (brake) position,
or by moving the Grip Lever A to the forward or back positions.
Accessing The End-Point
Adjustment Function
1. Turn on the transmitter power switch.
2. Press the Scroll key to enter Function mode.
3. Press the Scroll key until "EPA" appears in small letters on the left side of the screen.
4. Press the Channel key to select the desired channel to be adjusted.
Steering = ST R/B(steering right) or ST L/F (steering left)
Throttle = TH L/F (forward) or TH R/B (braking or reverse)
5. Move the steering wheel or trigger in the desired direction for adjustment (left/right,
forward/reverse or brake). Press the Increase or Decrease key to achieve the desired
amount of travel. Move the wheel or trigger in the opposite direction to adjust the travel
in the opposite direction.
6. Press the Scroll key to access the Sub-Trim function.
7. To exit the Function mode, either turn off the transmitter power switch or press the
Scroll and Channel keys at the same time.
Note: When setting the end point adjustment values for the steering function, it is
suggested that, if possible, the maximum travel values be set to an equal value in both
directions to maintain proper steering control.
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Sub-Trim (Function Mode)
The Sub-Trim function of the XR2i is an electronic trimming feature that allows the
neutral position of the servo on either the steering or throttle channel to be moved, while
allowing the electronic trim lever for that channel to remain in the center position. This
feature is very useful as it allows the servo arm/wheel position to be moved to help with

control linkage installation, eliminating the need to make mechanical linkage
adjustments.
Although the Sub-Trim function is a very useful feature, it is suggested that only small
amounts of sub-trim be used so that no unwanted, non-equal servo travel is created. It is
suggested that less than 30 points of Sub-Trim be used during adjustment. If more than
30 points of Sub-Trim are required, it is suggested that a mechanical linkage adjustment
be performed.
Accessing the Sub-Trim Function
1. Turn on the transmitter power switch.
2. Press the Scroll key to enter Function mode.
3. Press the Scroll key until "TRIM" appears in small letters to the left of the screen.
4. Press the Channel key to select the channel to be adjusted (Steering, Throttle or
Auxiliary Channel 3).
5. Press the Increase or Decrease keys until the proper servo position is achieved.
6. Press the Scroll key to access the Servo Reversing function.
7. To exit the Function mode, either turn off the transmitter power switch or press the
Scroll and Channel keys at the same time.
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Servo Reversing (Function Mode)
The Servo Reversing feature of the XR2i is a very convenient feature when setting up a
new model. The purpose of the servo reversing function is to change the direction of the
servo rotation in relation to the wheel/trigger movement. The Servo Reversing function is
available for the steering and throttle of the XR2i.
Accessing the Servo
Reversing Function
1. Turn the transmitter power switch on.
2. Press the Scroll key to access Function Mode.
3. Press the Scroll key until "REV.NORM" appears in small letters to the right of the
screen.
4. Press the Channel key to select the channel to be changed (ST = Steering, TH =
Throttle).
5. Press the Increase or Decrease keys to move the cursor to the desired direction.
6. To exit the Function mode, either turn off the transmitter power switch or press the
Scroll and Channel keys at the same time.
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Accessing the Direct Trim Mode

The Direct Mode function of the XR2i is accessible through the use of the electronic
throttle or steering trim levers, as well as the two electronic grip levers (A&B) located on
the upper portion of the grip handle. This function allows for quick trim adjustment of
these controls.
To access the Direct Trim Mode function, turn on the transmitter power switch. Next,
move the desired trim lever to be adjusted. The appropriate screen for the selected trim
lever will be displayed. To adjust, simply move the trim lever in the desired direction
until the correct amount of trim is achieved. Once the desired trim is achieved, the screen
will return to the Normal display screen after approximately two seconds from the last
trim input. If the Increase or Decrease keys are pressed any time during the two seconds,
the system will return to the previous screen in use.
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Steering Trim (STC)
The XR2i electronic Steering Trim lever, located just above the steering wheel, allows
the center position of the servo to be manipulated in either direction to achieve precise
centering of the steering assembly. Steering travel end-point adjustment values (page 24)
remain completely independent from the steering trim, unless the trim value exceeds the
selected end-point values. (For example, if trim values are set at 30 and end-point values
at 15, steering trim will over-ride/alter the end-point value.)
Each click will provide 0.3° of trim to the center of the steering servo with a maximum of
12° allowed.
Note: Each click will not always result in a change of the value displayed.
To adjust the steering trim servo position, move the electronic Steering Trim lever either
to the left or the right. As soon as the trim is moved, the "STC" Steering Trim screen will
appear and will continue to be displayed unless the trim lever is untouched for a period of
two seconds. To reset the trim value to 0, press the Increase and Decrease keys at the
same time while the "STC" screen is displayed.
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Throttle Trim (THC)
The XR2i's electronic Throttle Trim lever, located to the left of the steering wheel, allows
the center position of the servo to be manipulated in either direction to achieve precise
centering of the throttle trigger neutral position. Throttle end-point adjustment values
(page __) remain completely independent from the throttle trim, unless the trim value
exceeds the selected end-point values. (For example, if the trim value is set at 40 and the
end-point values at 30, Throttle Trim will override/alter the end-point value.)

Each click will provide 0.3° of trim to the throttle servo with a maximum of 24° allowed.
Note: Each click will not always result in a change of the value displayed.
To adjust the Throttle Trim servo position, move the electronic steering trim lever either
up or down. As soon as the trim is moved, the "THC" Throttle Trim screen will appear
and will continue to be displayed unless the trim lever is untouched for a period of two
seconds. To reset the trim value to zero, press the Increase and Decrease keys at the same
time while the "THC" screen is displayed.
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Grip Lever B: Steering Dual-Rate Trim Adjustment (STG)
The Steering Dual-Rate adjustment, located at Grip Lever B, allows the Dual-Rate value
(maximum servo travel) to be increased or decreased within a range from 100% through
20% of the total end point value established in the steering EPA function. This function is
very useful in race conditions as it allows you to custom tailor the steering radius and
sensitivity for the current track conditions.
Please note that since the Dual-Rate value shown in the "STG" screen is the percentage of
the end-point value established in the Steering EPA function, the value will not always
increase or decrease each time Grip Lever B is moved.
If the Emergency Steering button function (page __) is active, pressing Grip Button C
will restore the steering dual rate to 100% until the button is released.
To adjust the Steering Dual-Rate value, move the electronic Grip Lever B either left (-) or
right (+). As soon as the trim is moved, the “STG” Steering Dual-Rate screen will appear
and will continue to be displayed unless the Grip Lever B is untouched for a period of
two seconds. To reset the trim value to the factory preset setting of 70%, press the
Increase and Decrease keys at the same time while the "STG" screen is displayed.
page break___________***************_____**********_____**********______**********_______________
Grip Lever A: Brake End-Point Adjustment BRK/Auxiliary
Channel 3 Access
Brake End-Point Adjustment
The Brake End-Point Adjustment, located at Grip Lever A, allows the maximum servo
travel on the braking side of the throttle trigger to be increased or decreased from 100%
to 0% (off). This function is very useful in race conditions as it allows the racer to custom
tailor the "panic" brake value to maximize the car's braking power for the current track
conditions. Please note that since the Brake End-Point value shown in the "BRK" screen

is a percentage of the total braking value established in the End-Point Adjustment
function (page __), the value will not always increase or decrease each time the Grip
Lever A is moved.
To adjust the brake endpoint value, move the electronic Grip Lever A either left (-) or
right (+). As soon as the grip lever is moved, the BRK End-Point Adjustment screen will
appear and will continue to be displayed unless the Grip Lever A is untouched for a
period of two seconds.
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XR2i Data Sheet
System Mode
MODEL NUMBER 1 2
MODEL NAME
GRIP BUTTON C O/Eb
Function Mode
STEERING THROTTLE
END-POINT ADJUSTMENT L__________ R__________ F__________ B__________
SUB-TRIM
SERVO REVERSING REV/NORM REV/NORM
Direct Mode
TRIM STEERING THROTTLE
VALUES –/+ –/+
GRIP LEVER B
STEERING D/R %
BRAKE EPA
GRIP
LEVER A VALUES %
System Mode
MODEL NUMBER 1 2
MODEL NAME
GRIP BUTTON C O/Eb
Function Mode
STEERING THROTTLE
END-POINT ADJUSTMENT L__________ R__________ F__________ B__________
SUB-TRIM
SERVO REVERSING REV/NORM REV/NORM
Direct Mode
TRIM STEERING THROTTLE
VALUES –/+ –/+
GRIP LEVER B
STEERING D/R %
BRAKE EPA
GRIP
LEVER A VALUES %
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Frequency Chart
FREQUENCY (MHZ)CHANNEL FREQUENCY (MHZ)CHANNEL FREQUENCY (MHZ)CHANNEL
26.995 ..........................1
27.045 ..........................2

27.095 ..........................3
27.145 ..........................4
27.195 ..........................5
27.255 ..........................6
75.410 ........................61
75.430 ........................62
75.450 ........................63
75.470 ........................64
75.490 ........................65
75.510 ........................66
75.530 ........................67
75.550 ........................68
75.570 ........................69
75.590 ........................70
75.610 ........................71
75.630 ........................72
75.650 ........................73
75.670 ........................74
75.690 ........................75
75.710 ........................76
75.730 ........................77
75.750 ........................78
75.770 ........................79
75.790 ........................80
75.810 ........................81
75.830 ........................82
75.850 ........................83
75.870 ........................84
75.890 ........................85
75.910 ........................86
75.930 ........................87
75.950 ........................88
75.970 ........................89
75.990 ........................90
FREQUENCY CHART
Transmitter Crystal Replacement Notice
The Federal Communications Commission (FCC) requires that changes in transmitter
frequency must be preformed only by an authorized service technician (Horizon Service
Center). Any transmitter frequency changes made by a non-certified technician may
result in a violation of the FCC rules.
page break___________***************_____**********_____**********______**********_______________

Warranty and Service Information
Note: Be sure to keep your original dated sales receipt in a safe place as you will be
required to provide proof of purchase date for the equipment to be serviced under
warranty.
Warranty Coverage
Your new JR Remote Control Radio System is warranted to the original purchaser
against manufacturer defects in material and workmanship for 3 years from the date of
purchase. During this period, Horizon Service Center will repair or replace, at our
discretion and at no cost to the purchaser, any component that is found to be factory
defective. This warranty is limited to the original purchaser of the unit and is not
transferable.
This warranty does not apply to any unit that has been improperly installed, mishandled,
abused or damaged in a crash or to any unit which has been repaired or altered by any
unauthorized agencies. Under no circumstances will the buyer be entitled to
consequential or incidental damages. This limited warranty gives you specific legal
rights; you also have other rights, which may vary from state to state. As with all fine
electronic equipment, do not subject your radio system to extreme temperatures, humidity
or moisture. Do not leave it in direct sunlight for long periods of time.
Repair Service Directions
In the event that your JR radio needs service, please follow the instructions listed below.
1. Check all on/off switches to be sure they are off. This will speed the repair process of
checking battery condition.
2. Return your system components only (transmitter, receiver, servos, etc.). Do not return
your system installed in a model car, boat, etc.
3. Preferably, use the original carton/packaging (molded foam container) or equivalent to
ship your system. Do not use the system carton itself as a shipping carton. You should
package the system carton within a sturdy shipping container using additional packing
material to safeguard against damage during transit. Include complete name and address
information inside the carton, as well as clearly writing it on the outer label/return
address area.
4. Include detailed information explaining your operation of the system and problem(s)
encountered. Provide an itemized list of equipment enclosed and identify any particular
area/function, which may better assist our technicians in addressing your concerns. Date
your correspondence and be sure your complete name and address appear on this
enclosure.
5. Include you name, mailing address and a phone number where you can be reached
during the business day.
6. Within your letter, advise us of the payment method you prefer to use. The Horizon
Service Center accepts only VISA or MasterCard. Please include your card number and
expiration date.

Warranty Repairs
To receive warranty service, you must include your original dated sales receipt to verify
your proof-of-purchase date. Providing that warranty conditions have been met, your
radio will be repaired without charge.
Normal Non-Warranty Repairs
Should your repair cost exceed 50% of the retail purchase cost, you will be provided with
an estimate advising you of your options.
Ship your system to:
Horizon Service Center
4105 Fieldstone Road
Champaign, IL 61822
Phone: [phone]
(UPC=4944013000366
Item#= JRPM128
©Copyright 2002 Horizon Hobby, Inc.