26 • 1/16 SUMMIT VXL
Your Traxxas transmitter has a programmable Multi-Function knob
that can be set to control various advanced transmitter functions (set to
Traxxas Stability Management (TSM) by default, see page 15). Accessing
the programming menu is done by using the menu and set buttons on
the transmitter and observing signals from the LED. An explanation of
the menu structure follows on page 29. Experiment with the settings
and features to see if they can improve your driving experience.
Steering Sensitivity (Exponential)
The Multi-Function knob on the TQi transmitter can be set
to control Steering Sensitivity (also known as exponential).
The standard setting for Steering Sensitivity is “normal (zero
exponential)”, with the dial full left in its range of travel. This setting
provides linear servo response: the steering servo’s movement will
correspond exactly with the input from the transmitter’s steering
wheel. Turning the knob clockwise from the left will result in
“negative exponential” and decrease steering sensitivity by making
the servo less responsive near neutral, with increasing sensitivity
as the servo nears the limits of its travel range. The farther you
turn the knob, the more pronounced the change in steering servo
movement will be. The term “exponential” comes from this effect;
the servo’s travel changes exponentially relative to the input
from the steering wheel. The exponential effect is indicated as a
percentage—the greater the percentage, the greater the effect.
The illustrations below show how this works.
Normal Steering Sensitivity
(0% exponential):
In this
illustration, the steering servo’s
travel (and with it, the steering
motion of the model’s front
wheels) corresponds precisely
with the steering wheel. The
ranges are exaggerated for
illustrative purposes.
Decreased Steering Sensitivity
(Negative Exponential):
By
turning the Multi-Function
knob clockwise, the steering
sensitivity of the model will
be decreased. Note that a
relatively large amount of
steering wheel travel results
in a smaller amount of servo
travel. The farther you turn the
knob, the more pronounced
the effect becomes. Decreased steering sensitivity may
be helpful when driving on low-traction surfaces, when
driving at high speed, or on tracks that favor sweeping turns where gentle steering
inputs are required. The ranges are exaggerated for illustrative purposes.
Throttle Sensitivity (Throttle Exponential)
The Multi-Function knob can be set to control Throttle Sensitivity.
Throttle Sensitivity works the same way as Steering Sensitivity, but
applies the effect to the throttle channel. Only forward throttle
is affected; brake/reverse travel remains linear regardless of the
Throttle Sensitivity setting.
Steering Percentage (Dual Rate)
The Multi-Function knob can be set to control the amount
(percentage) of servo travel applied to steering. Turning the Multi-
Function knob fully clockwise will deliver maximum steering throw;
turning the knob counter-clockwise reduces steering throw (note:
turning the dial counter-clockwise to its stop will eliminate all servo
travel). Be aware that the steering End Point settings define the
servo’s maximum steering throw. If you set Steering Percentage to
100% (by turning the Multi-Function knob fully clockwise), the servo
will travel all the way to its selected end point, but not past it. Many
racers set Dual Rate so they have only as much steering throw as
they need for the track’s tightest turn, thus making the model easier
to drive throughout the rest of the course. Reducing steering throw
can also be useful in making a model easier to control on high-
traction surfaces, and limiting steering output for oval racing where
large amounts of steering travel are not required.
Braking Percentage
The Multi-Function knob may also be set to control the amount
of brake travel applied by the servo in a nitro-powered model.
Electric models do not have a servo-operated brake, but the Braking
Percentage function still operates the same way in electric models.
Turning the Multi-Function knob full clockwise will deliver maximum
brake throw; turning the knob counter-clockwise reduces brake throw
(
Note
: Turning the dial counter-clockwise to its stop will eliminate all
brake action).
Throttle Trim
Setting the Multi-Function knob to serve as throttle trim will allow
you to adjust the throttle’s neutral position to prevent unwanted
brake drag or throttle application when the transmitter trigger is
at neutral.
Note
: Your transmitter is equipped with a Throttle Trim
Seek mode to prevent accidental runaways. See the sidebar for more
information.
TQ
i
ADVANCED TUNING GUIDE
Starting Over:
Restoring Factory Defaults
When programming your
TQi transmitter, you may feel
the need to start over with
a clean slate. Follow these
simple steps to restore the
factory settings:
1. Turn the transmitter off.
2. Hold both MENU and SET.
3. Turn the transmitter on.
4. Release MENU and SET.
The transmitter LED will
blink red.
5. Press SET to clear settings.
The LED will turn solid
green and the transmitter
is restored to default.
Throttle Trim Seek Mode
When the Multi-Function knob is
set to throttle trim, the transmitter
remembers the throttle trim
setting. If the throttle trim knob is
moved from the original setting
while the transmitter is off, or while
the transmitter was used to control
another model, the transmitter
ignores the actual position of
the trim knob. This prevents the
model from accidentally running
away. The LED on the face of the
transmitter will rapidly blink green
and the throttle trim knob (Multi-
Function knob) will not adjust the
trim until it is moved back to its
original position saved in memory.
To restore throttle trim control,
simply turn the Multi-Function
knob either direction until the LED
stops blinking.
Turning Range
at Transmitter
Effective Turning
Range on Model
