Lemon Rx StabilizerPLUS LM0042 User manual

V. 1.5 – Updated 2022, February 28
Lemon RX StabilizerPLUS
7-Channel Receiver – LM0042/43/44
Essential Instructions
Contents
Introducing the Lemon Stabilizer PLUS ....................................................................................................2
Requirements.........................................................................................................................................3
Functions ........................................................................................................................................................ 3
Transmitter Requirements.............................................................................................................................. 3
Servos and Power Sources.............................................................................................................................. 4
Setting up the StabPLUS..........................................................................................................................5
Installation...................................................................................................................................................... 5
Binding............................................................................................................................................................ 6
Setting Failsafe................................................................................................................................................ 7
Flying.....................................................................................................................................................7
Preparing for the First Flight........................................................................................................................... 7
First Flight....................................................................................................................................................... 9
Setting up the Stabilizer PLUS in more Advanced Models ............................................................................. 9
Adjusting Gain .............................................................................................................................................. 10
Resetting the Stabilizer.........................................................................................................................11
Resetting Level and Alignment (Toggle during initialization) ....................................................................... 11
Resetting Stick Neutrals (Toggle after initialization)..................................................................................... 12
Calibration of the Sensors (no action normally needed) ............................................................................. 13
Special Options ....................................................................................................................................13
Stabilizer Always-ON (requires Rebind)........................................................................................................ 13
Mode Order and Autolevel Setting (Bind Plug on channels 4, 5, 6)............................................................. 14
Hardware Reset (Bind Plug across channels 2, 3, 4)..................................................................................... 14
Other Issues......................................................................................................................................... 15
IMPORTANT: Don't use Autolevel with Flaperons or Aileron Differential.................................................... 15
Using Other Mixes with Autolevel................................................................................................................ 15
IMPORTANT: Don’t Use Elevon and V-tail Mixing in the Transmitter........................................................... 16
Alignment and Mounting of the StabPLUS................................................................................................... 16
Annexes ...............................................................................................................................................17
Annex A: What do those tiny cryptic letters on the label mean? ................................................................ 17
Annex B: Stabilizer Mode Settings................................................................................................................ 17
Annex C: Setting up a Current Generation Spektrum Transmitter for the StabPLUS................................... 17
Annex D: Using a Two-Position Switch to Control Stabilization ................................................................... 18
Annex E: Setting up a DX6i for the StabPLUS ............................................................................................... 18
Annex F: Using Channel 7 on the Lemon Stabilizer (v4 and v4.5) and StabPLUS......................................... 18
Further Information
For more detailed information see the Reference Guide to the Lemon RX Stabilizer PLUS.
A number of short instructional videos for the Stabilizer PLUS are available on the same RCGroups post.
To offer comments or raise questions about the Stabilizer PLUS or the instructions, please go to The Official
Lemon STABILIZER PLUS thread on RC Groups.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Introducing the Lemon Stabilizer PLUS
Building on the great success of its basic 7-channel stabilized receiver, Lemon RX developed the Stabilizer
PLUS with the following additional features and capabilities:
•Seven fully usable channels (when using Always-ON feature or with stabilization switched OFF)
•Flexible installation, including inverted and on-edge mounting
•Gyro mode for rate-stabilization to smooth out response and counteract turbulence
•Autolevel mode with restricted bank and pitch, also provides emergency recovery
•Level Reset feature to compensate for out of level effects
•Trim Reset feature to correct for trim and subtrim offsets
•Hardware Reset capability
•Dual aileron, plus elevon and V-tail mixing capability
•Usable with simple transmitters such as DX5e, as well as fully programmable ones
•DSMX/DSM2-compatible
•Available with either single antenna or dual diversity antennas:
oSingle antenna, top pin: LM0042
oDual diversity antenna, top pin: LM0043
oDual diversity antenna, end pin: LM0044
The StabPLUS does not replace the basic Lemon Stabilizer; each has its advantages and limitations:
Basic Lemon Stabilized Receiver
•Provides only rate (Gyro) stabilization. Does not support Autolevel function.
•Relatively simple to setup and adjust.
•Supports a remote receiver (satellite) and is available with dual diversity antenna.
•Six channels available for flight control (channel 5 is dedicated to stabilization on/off).
•Limited flexibility in mounting (does not directly support on-edge installation).
Lemon Stabilizer PLUS Receiver
•Provides Autolevel mode, in addition to rate (Gyro) stabilization.
•More complex to setup and adjust.
•Does not support a remote receiver (satellite), but is available in dual diversity antenna version.
•Seven channels available for flight control when in Always-ON mode (six channels in normal mode).
•Allows mounting upright, inverted or on edge.
Thus the basic Lemon Stabilizer is quicker and easier to install and set up, whereas the StabPLUS offers
greater flexibility and capability for those willing to invest the time in these more complex instructions.
Application
The Lemon StabilizerPLUS receiver was conceived initially as a simple and inexpensive way to provide
AutoLevel and Panic Recovery capability for beginners and RC pilots with limited skills. It was also intended
to help FPV (First Person View) flyers seeking a stable platform for aerial photography. Thus, the primary
application of the StabPLUS was seen as relatively mild and stable models, including trainers.
However, the StabPLUS functions very well in Gyro mode as a rate stabilizer, making it suitable for more
advanced and responsive models. Moreover, the additional features of the StabPLUS are very useful in some
circumstances. In particular, the ability to use all seven channels by setting the unit to Always-ON supports
models with dual ailerons, flaps and retractable landing gear, while the option to mount the stabilizer on
edge without any complex adjustments at the transmitter is useful for profile models. To use the StabPLUS
in more advanced models, be sure to read the discussion on page 9.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Warnings
•The Autolevel feature of the StabPLUS should not be seen as a substitute for adequate basic flying skills.
Safely setting up this unit requires that the model be flown with stabilization OFF, as well as in Gyro
and/or AutoLevel modes.
•The StabPLUS is not a substitute for Spektrum SAFE Technology® or other advanced stabilization
systems such as the Eagletree Guardian.® Used within its capabilities, it can improve the smoothness
and stability of a wide range of models, and can help to recover from difficult situations, but to function
correctly it must be properly set up for the specific model.
•Autolevel is NOT recommended for use in conjunction with Always-ON. See page 13.
•Beginners should recognize that Autolevel gives a form of control quite unlike “normal” RC flying.
Learning to fly RC with Autolevel turned on full time will develop habits that are hard to break later.
Requirements
These Essential Instructions cover information that most people will need to get the Lemon Stabilizer PLUS
up and flying. The separately available Reference Guide not only provides additional information on the
functioning of the Stabilizer PLUS, but also covers in more detail such topics as transmitter programming
and using Delta Wing (elevon), V-tail and Flaperon mixes.
These documents are prepared by jj604 (John) and Daedalus66 (Nigel). We have worked closely with the
people at Lemon RX but are not paid by, or associated with, the manufacturer.
Functions
As it arrives, the StabPLUS has all DIP switches (J1-J6) set to OFF. In this configuration it behaves as a fully
functional, unstabilized, seven channel, DSMX/DSM2-compatible receiver with excellent performance.
When activated by setting J4 and/or J5 to ON, the unit becomes a receiver with six usable flight channels
(1-4 and 6-7) having three stabilization modes, controlled by channel 5 (Gear):
1. OFF: No stabilization.
2. Gyro: Rate stabilization counteracts turbulence for smoother flight.
3. Autolevel: Limits pitch and bank angles and returns the model to level if the sticks are released.
The direction of stabilization action is determined by the positions of switches J1, J2, J3.
The StabPLUS can also be set to Always-ON, allowing all seven channels (including channel 5) to be used for
flight functions. Always-ON is only recommended for use with Gyro mode, NOT Autolevel (see page 13).
Transmitter Requirements
The Lemon Stabilizer PLUS receiver requires a Spektrum® or other transmitter using Spektrum DSM2® or
DSMX® technology. Examples: DX4e, DX5e, DX6i, DX6, DX7s, DX8, DX8G2, DX9, DX18, iX12 and JR 9503.
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A three-position switch controlling channel 5 (Gear) is required if all three stabilization modes (OFF, Gyro,
Autolevel) are to be available in flight. Later DX4e and DX5e transmitters provide such a switch, while more
advanced transmitters can generally be programmed to output the necessary 100%/ 0%/-100% on
channel 5 (Gear).
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The Lemon Stabilizer PLUS receiver may not work properly with the Spektrum® DM8 and DM9 transmitter modules
or with certain non-Spektrum equipment, including most OrangeRX® transmitter modules. Modules using
Multiprotocol firmware, such as the various 4in1 types, should be compatible. This is the most popular way to use a
StabilizerPLUS with an FrSky Taranis or Horus or a Turnigy 9XR Pro.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Transmitters with only a two-position switch on channel 5, such as the older examples of DX4e and DX5e, as
well as programmable ones that lack the ability to assign a suitable three-position switch, can be set to
access either Gyro or Autolevel, but not both, as explained under Changing Mode Order (see page 9).
Alternatively, many such transmitters, including specifically the DX6i, can be programmed to control the
three modes by means of a pair of two-position switches. See Annexes D and E and the Reference Guide for
detailed information.
Servos and Power Sources
The Stabilizer PLUS receiver works well with a wide range of servos, both analog and digital. For optimum
stabilization, servos with relatively fast response times are preferred. Metal-gear servos may be used for
their shock resistance but they too are optional.
Be sure to use an ESC (speed control), BEC (battery eliminator) or battery with ample current capacity to
power the radio. Stabilization makes the servos work harder than unstabilized flight and thus generates
significantly higher current drain. A good rule to follow is to choose a BEC, whether internal to the ESC or
separate, that has at least 50% more capacity than you would use for a similar but unstabilized model. An
adequate power supply is vital because although the Stabilizer PLUS is highly resistant to short power
interruptions (<1s), after a longer power loss, several seconds are needed for a reset.
If possible, use a switching-type BEC (SBEC), either in the ESC or as stand-alone unit, for its ability to deliver
power without overheating and to cope with higher battery voltages. Linear BECs can also be satisfactory as
long as you stay within their voltage and servo limits.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Setting up the StabPLUS
Installation
These instructions are intended to explain the basic steps in setting up the Lemon Stabilizer PLUS for a
conventional model (no elevons or V-tail). The following channel assignments are used:
CH1 - Throttle
CH2 - Ailerons (or Right Aileron if dual servos on separate channels are used)
CH3 - Elevator
CH4 - Rudder
CH5 (Gear) - Dedicated to selection of Stabilizer Mode, generally not usable for any other purpose
(unless Always-ON is used, see page 13)
CH6 (Aux1) - Left Aileron (only if dual servos on separate channels are used), or other function
CH7 (Aux2) - Available for other function (also used for Bind)
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CH8 (Aux3) - Dedicated to Master Gain, not usable for any other purpose
For details on other configurations, see the Reference Guide. Note that if Elevon (Delta) or V-tail mixing is
required, it MUST be done in the Stabilizer, not in the transmitter. See also page 16.
Basic Setup
Start by creating a new model in the transmitter or do a reset on the chosen model memory. For a recent
Spektrum transmitter, if the model has a single aileron servo or dual aileron servos on a Y-cable, choose
Normal Wing Type in the Aircraft Type menu. This menu is called Wing Type in some older transmitters.
Set stabilizer switches J4 and J5 to ON. Use a pin to change switch settings, making sure the switch snaps
over completely.
For a model with two aileron servos on separate channels, select Dual Aileron Wing Type. In this case, also
set switch J6 ON to activate aileron stabilization on channel 6 (Aux1).
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For a DX6i, select WingTailMix, Dual
Aileron.
To control Stabilization Mode, Channel 5 (Gear) should be assigned to a three-position switch if possible.
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On recent Spektrum programmable transmitters, go to Channel Assign, Channel Input Config and select a
three-position switch (such as B or D). For a DX6i, see Annex D (page 18).
If your transmitter has eight or more channels, set up a knob or slider for channel 8 (Aux3) to control
Master Gain. On recent Spektrum transmitters, this is done in Channel Assign by setting Aux3 to be
controlled by a knob (RKnb). The direction of increasing gain can be changed by reversing the channel (look
at the Monitor screen to determine which way is increasing). Note that channel 8, if available, cannot be
used for any function other than Master Gain.
Installation
The most common installation has the Stabilizer PLUS upright in the aircraft (i.e., flat on a surface that is
horizontal when the model is in normal level flight attitude). The long axis of the unit must be aligned with
2
Note that channel 7 (Aux2) is also used for binding the receiver. There may be a problem if this channel is used to
operate certain types of retractable landing gear. If this is the case, use another channel for retracts. See Annex F.
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Flaperon Wing Type should only be used if you take precautions to prevent the use of the flaperon mix in Autolevel
mode. Likewise, Aileron Differential must not be used in Autolevel mode. See page 14.
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See Annex D for discussion of using a two position switch.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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the flight direction and the servo connectors should be to the rear of the aircraft.
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For other possible
orientations and advice on mounting the StabPLUS, see page 16 and the Reference Guide.
Because the Stabilizer PLUS uses accelerometers as well as gyros (so is
sometimes called a “6-axis” stabilizer), for best performance it should be
located reasonably close to the center of gravity of the model.
Check that the three gain pots are set to their mid-points – i.e., 12 o’clock
(straight up – see picture). This is the starting point for adjustment.
To gain familiarity with the StabPLUS, it’s a good idea to test bind the
stabilizer on the bench, without servos attached, before installing in the
model.
Binding
1. Insert a bind plug into the Bind/channel 7 slot.
2. With the transmitter turned OFF, apply power to the stabilizer. The Red and Green lights of Indicator 2
(and the Red internal light) should flash rapidly to indicate that stabilizer is in Bind Mode.
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3. Turn ON the transmitter in Bind Mode (see the instructions for your transmitter). The transmitter
should be separated from the stabilizer by 1-2m (3-6 feet). In some cases,
even more separation may be needed for binding.
4. Wait until the transmitter indicates “bind complete” or the rapid
Red/Green flashing stops. If your bind process involves holding a button or
switch, hold for a couple of seconds more, then release.
5. Wait up to 20 seconds or so for the initialization process to complete, as
indicated by: Indicator 1 (Green/Blue) lights no longer flashing, Indicator 2
(Red/Green) lights signaling stabilizer mode (see below), and the
transmitter acquiring control of the servos.
6. Power down the stabilizer and transmitter. IMPORTANT: Don’t forget to remove the bind plug.
To test the bind, turn on the transmitter and then the stabilizer. Wait for initialization to complete. Verify
control of stabilization by placing the channel 5 (Gear) switch in each of its positions. A three-position
switch should cause the stabilizer to display the following:
Position 0: OFF – Red/Green solid (or flickering very slightly); no servo movement when model is rotated.
Position 1: Gyro – Green ON solid, Red OFF; servos move briefly when model is rotated.
Position 2: Autolevel – Red and Green lights flashing alternately; aileron and elevator servos stay
deflected when model is not level, rudder servo moves briefly when model is rotated (yawed).
With a two-position switch for channel 5, only OFF and Autolevel mode will be available by default. This can
be changed to OFF and Gyro, as explained under Changing Mode Order (see page 14).
5
Lemon RX have not tested the stabilizer with the pins oriented towards the front of the model, but users have
reported installing it this way without problems.
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If this rapid flashing of Indicator 2 does not happen, there is no possibility of binding. Do not proceed further till you
find the problem. Low voltage, reversed plugs or a defective bind plug are among the possibilities to check.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Setting Failsafe
No-pulse failsafe: By default, the receiver will, on loss of signal,
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stop sending pulses to the servos and ESC.
This should cause the ESC to cut power to the motor, while the servos stay where last commanded. This
achieves the basic failsafe requirement for most electric models – stopping the motor – although the ESC
may take three or four seconds to respond.
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Pre-set Failsafe is also available. Using this, the stabilizer will, on loss of signal, go to previously chosen pre-
set positions on all channels. Pre-set Failsafe has the advantage of operating more quickly, especially
important in cutting power to the motor.
To enable Pre-set Failsafe:
1. With receiver and transmitter powered down, insert a bind plug in the Bind/channel 7 slot.
2. Power up the receiver. Indicator 2 lights should be flashing rapidly to signal Bind Mode.
3. Power up the transmitter in Bind Mode (see instructions for your transmitter).
4. Allow the bind process to complete, until Indicator 1 lights (Green/Blue) have stopped flashing and
Indicator 2 lights are signaling the current stabilization mode. This may take up to 20 seconds or more.
5. Move the relevant transmitter sticks and switches to the desired failsafe positions.
6. Press the stabilizer button briefly (<1s) and release. Indicator 1 Green light ON shows failsafe is set.
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7. Remove the bind plug and power cycle the unit.
The failsafe settings will be retained even when the stabilizer is powered off.
To cancel Pre-set Failsafe settings, repeat the above procedure and again press the button briefly.
Always test failsafe by switching the transmitter OFF (with propeller removed or the model restrained).
Flying
The following assumes that the stabilizer is mounted upright in a trainer-type model with Autolevel
available. For use in other types of model, see the section “Setting up the StabilizerPLUS in more Advanced
Models” on page 9.
Preparing for the First Flight
Always remove the propeller or disconnect the motor before working with the battery plugged in.
1. With the receiver already bound, power up first the transmitter and then the receiver.
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2. Wait for the receiver to complete its initialization (up to 20 seconds).
3. With the stabilizer mode set to OFF (Indicator 2: Red and Green ON solid), verify that all control
surfaces travel in their correct directions when the transmitter sticks are moved. If necessary, change
the relevant Reverse settings in the transmitter. At this time check that all control surfaces are centered.
Note: If using a Transmitter with two-position Gear switch, skip step 4 or step 5, as appropriate.
7
Note that loss of power is quite different from loss of signal (out of range) although the results may seem similar.
8
IC (fuel powered) models must use correctly set up Pre-set Failsafe to shut down the engine on loss of signal.
9
If the BLUE light comes on, you have held the button too long and selected Always-ON. Press the button again for
more than 1 second to cancel this, then to set failsafe, press briefly (<1s) while holding the desired control inputs.
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The general rule is transmitter FIRST ON, LAST OFF.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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4. Set the stabilizer mode to Autolevel (Indicator 2: Red and Green alternately flashing slowly). Rotate the
model about the pitch and roll axes and watch for the ailerons and elevator to deflect and stay deflected
when it is not level.
The directions of the stabilizer action on the aileron and elevator axes MUST be as follows:
•If the model is rolled to the right: right aileron goes DOWN and the left UP to level the model.
•If the nose of model is pitched down: elevator goes UP to restore the model to level flight.
The rudder is also stabilized but reacts differently:
•If model is yawed (rotated) to the right, the rudder pulses LEFT momentarily to resist the
displacement, then returns to neutral (as in Gyro mode – see Step 5).
If any response is incorrect, use the appropriate switch J1, J2 or J3 to reverse the action and test again.
Note that the labels ON and OFF have no specific meaning for these switches.
5. Set the stabilizer to Gyro mode (Indicator 2: Green ON, Red OFF) and test the stabilizer action on each
of the control axes. Directions of movement should be as above, except that this time what you are
looking for on all three axes is a pulse of movement of the control surface which occurs while the
model is starting to move from stationary.
For example, in Gyro mode, when you roll the model sharply to the right, the right aileron should for a
moment go DOWN and the left UP (to oppose the displacement), then they should return to neutral. (If
the direction of stabilization movement for aileron and elevator is correct for Autolevel mode it will also
be correct for Gyro mode.)
If the stabilizer motion in Gyro mode is hard to interpret, turn the three gain pots fully clockwise to
increase gain (or turn up Master Gain, if available). Note that it is often easier to feel the direction of
deflection with your finger on the control surface hinge than to see it. Additional information on
stabilizer response is provided in the Reference Guide.
6. Carefully recheck the directions of BOTH control movement AND stabilizer action – a mistake here can
have serious consequences! In summary: correct response to stick input is set in the transmitter,
correct response to a disturbance is set in the stabilizer.
7. Check that the three gain pots on the stabilizer are set close to 12 o’clock as a starting point.
8. If available, set Master Gain to the midpoint (i.e., 0% on the transmitter’s monitor screen). If your
transmitter has less than eight channels, Master Gain is fixed at 1, which is 0%, and you can skip this.
9. Check that the flight control trims are set to zero. If necessary, use a little Sub-trim to align the servo
arms at right angles to the pushrods. Adjust mechanical settings to center the control surfaces.
10. Test failsafe by turning off the transmitter with the motor running (make sure your prop is removed or
the model is restrained). The motor should stop within two or three seconds if No-pulse Failsafe is used
or almost immediately if Preset Failsafe is correctly set. Turn the transmitter back ON and the motor
should restart. (Do this failsafe test on the ground, NOT in flight!).
11. Make sure you know how to find the Stabilizer Mode switch without having to look down at the
transmitter and that you know how to turn it OFF quickly if there is a problem with the settings.
12. It is recommended that you set up Dual Rates on the transmitter with Low Rate being about 70% and
High Rate 100%.
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Use mechanical adjustments and/or servo travel (called Travel, ATV or End Point
Adjust depending on the transmitter) to set control throws to those recommended for the model.
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Triple rates can also be used, with Mid Rate set to say 85%. The actual percentage values depend on the
aerodynamics and responsiveness of the particular model.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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13. You may also wish to add 20% Expo, or somewhat more, to soften control responses around neutral,
but keep in mind that stabilization has an expo-like effect.
First Flight
1. Power up first the transmitter and then the receiver.
2. Wait 20 seconds or so until initialization is complete, and the transmitter has control of the servos.
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3. Once again check the directions of (1) control and (2) stabilization movement. Aileron can be confusing
– to deliberately bank to the right, the right aileron goes UP, whereas in correcting for a disturbance that
causes the right wing to drop, the stabilizer makes that aileron go DOWN! Think this through carefully.
4. Set Stabilizer Mode switch (channel 5/Gear) to OFF.
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5. Take off and climb to a safe height.
If you have a two-position switch giving access only to Off and Autolevel, go to step 8 below.
6. Turn ON Gyro mode (Position 1 on a three-position switch). Expect Gyro mode to cause the model to fly
more smoothly, resist wind gusts, and be somewhat less sensitive to control inputs than with the
stabilizer OFF. If there are any unexpected reactions, immediately turn OFF the stabilizer (Position 0)
and land to trouble-shoot.
7. If you see oscillation on any axis, slow down and land (or slightly turn down Master Gain, if you have it).
Turn the relevant pot(s) down (CCW) by an “hour” or so. See Adjusting Gain on page 10 for detail on
adjusting gain and the Reference Guide for further advice.
8. Switch to Autolevel mode (Position 2). In Autolevel mode, you should find the model much more docile,
with a strong tendency to return to level when you neutralize the sticks. You will still have control, but
turns may require significantly more input and maximum bank and pitch will be limited. To increase
control authority, you can use High Rate and/or change to Advanced Autolevel mode in the stabilizer
configuration, which allows steeper bank angles (see page 14). Be ready to switch to OFF or Gyro if you
encounter a problem.
9. If the model (with throttle set appropriately) does not maintain level flight in Autolevel mode, switch to
OFF or Gyro mode, land and reset Stabilizer Level and Stick Neutrals, as explained below.
If you are a beginning flier looking to use the Lemon Stabilizer PLUS to assist you in developing your
piloting skills, we strongly recommend enlisting the help of an experienced pilot for the first flights.
Setting up the Stabilizer PLUS in more Advanced Models
For fast and/or highly responsive models, it is generally advisable to use the Stabilizer PLUS in rate (Gyro)
mode for normal flying. In this mode the stabilizer responds only to angular displacements by applying
corrective movement of the appropriate control surface(s). For example, if a wind gust lifts one wing and
pitches the nose of the model up, the stabilizer would apply a quick shot of opposite aileron and down
elevator to counteract the disturbance. The result of using Gyro mode is that the model flies more
smoothly, especially in turbulent conditions. In practice, many fliers say it feels like flying a much bigger
model less affected by turbulence.
In contrast to AutoLevel, in Gyro mode the model does not seek to recover to level flight but responds
essentially “naturally” to control inputs. This is exactly what is needed for “normal” flying with the pilot fully
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A flashing orange light in DSM2 mode indicates that there has been an interruption of receiver power. This could be
because receiver power was reconnected without first cycling transmitter power. This “Brown-out Detection” feature is
not present for DSMX mode. To stop the flashing, power down both receiver and transmitter and repeat power-up.
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Don’t use stabilization for the initial takeoff unless you are absolutely confident that you have set the response
directions correctly. Then use only Gyro mode.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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in command.
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Learning pilots should be sure to wean themselves off dependence on Autolevel mode as
they build basic flying skills.
There are several ways to use the Lemon StabilizerPLUS in relatively maneuverable or fast models:
1. Default configuration with a three-way mode switch, using OFF (position 0) and Gyro (position 1) as the
primary modes. This facilitates accessing AutoLevel (position 2) when desired. However, it also makes
accidentally selecting Autolevel very easy – perhaps too easy.
2. Gyro mode with AutoLevel disabled. This is probably the preferred arrangement for many people who
want to use some of the advanced features (such as Always-ON or on-edge mounting) but not Autolevel.
3. Gyro mode with Panic Recovery. In this arrangement, AutoLevel is activated by a momentary switch or
button and is used only to restore the model to level flight.
Here are some suggestions for setting up the various configurations.
1. Default Configuration
Just follow the instructions already provided under “Setting up the StabPLUS”, starting on page 5.
2.. Pure Gyro Mode (Autolevel disabled)
a. Change the StabPLUS mode order to OFF/AutoLevel/Gyro, as explained on page 14. Then use a two-
position switch to provide 100/-100 settings. OR
b. Leave mode order at the default OFF/Gyro/AutoLevel, but use the Digital Switch Setup feature of a recent
Spektrum transmitters to set a three-position switch (such as B or D) on channel 5 (Gear) to give 100/0/0.
3. Gyro mode with Panic Recovery
One way to do this is to use Digital Switch Setup to set a two-position switch (such a A) to give 100/0 on
channel 5 (Gear), thus enabling OFF/Gyro. Then create a mix to use the bind button (I) to invoke AutoLevel
by driving channel 5 to -100% when pressed. Such a mix is -I- > GER, Rate: 0%, 100%, Offset 100%, Switch I.
Adjusting Gain
The preceding instructions will get the StabPLUS working quite well, but they will not ensure that the
optimum gain settings are achieved. Whether optimizing gain matters to you is a personal decision, but you
should at least understand the significance of gain and how to adjust it further if desired.
Gain is a measure of the amount of feedback involved in the stabilization loop. Using the stabilizer pots, gain
is set separately for each of the three stabilized channels (A, E, R). If gain for a channel is set too low, the
stabilization effect will be weak or non-existent. If it is set too high, the model will display oscillation at
higher speeds. The maximum allowable gain for a channel may vary between Gyro mode and Autolevel
mode: gain for each channel should be set to the lower of the Gyro or Autolevel value.
Transmitter with 7 or Fewer Channels (no Master Gain)
The aim here is to set each of the three stabilized channels (A, E, R) just below its maximum gain for Gyro
mode or Autolevel mode, whichever is lower. This can only be done by making repeated flights.
First test is done in Gyro mode. If oscillation is observed on one or more axes, land and turn down the gain
on the related pot(s) (counter-clockwise). Adjust the pot in small increments (about one “hour” at a time).
Fly and adjust repeatedly until no oscillation is observed on any axis. Then do the same in Autolevel mode.
It may be that no further adjustment is needed, but if you see oscillation, reduce gain on the relevant pot(s).
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Gyro mode is the Lemon equivalent of AS3X stabilization, the basic mode provided by Spektrum stabilized receivers.
AutoLevel is roughly similar to SAFE Technology Beginner mode in Spektrum.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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To achieve optimum gain, it is necessary to increase the gain for any axes(s) that did not show oscillation in
the above test. Increase the gain in small increments, testing both Gyro and Autolevel mode, always looking
for oscillation at increased airspeed. When you encounter oscillation, reduce gain by one “hour”.
When the process is completed, the three pots will likely have significantly different settings.
Transmitter with 8 or more Channels (supports Master Gain)
If your transmitter has eight or more channels, channel 8 (Aux3) is devoted to Master Gain and should be
controlled by a knob, lever or slider. Master gain multiplies the individual gain settings by a common factor
on all 3 axes. With this control centred (0%) the gain is 1. In other words, at the central position, Master
Gain will have no effect on the gains set by the individual pots.
15
To use Master Gain to aid in optimizing gain, test one axis at a time. On the ground, start with the Master
Gain knob on the transmitter centred and the aileron pot on the receiver at 12 o’clock; turn the other two
stabilizer pots fully counter-clockwise (minimum gain). Take off in Gyro mode and adjust Master Gain until
oscillation in the roll axis just occurs during a shallow dive. This may require either an increase or a decrease
in Master Gain. Now repeat for Autolevel and reduce gain further if necessary. You want the Stab to be on
the verge of oscillation, whether for Gyro or Autolevel.
Land and adjust the stabilizer. Let’s say you found that Master Gain at 2 o’clock was the best setting, just
short of oscillation. So you should then set the stabilizer aileron pot to 2 o’clock and return Master Gain to
its mid-position (0% on the transmitter monitor). Record the position of the Aileron pot for future use.
To adjust the pots for the other axes, start by setting the Aileron pot to minimum gain (full counter-
clockwise). Repeat the above process for the Elevator axis, then for Rudder, to find the “just short of
oscillation” settings for each. Finally set all three pots to the positions you have noted and back off Master
Gain “one hour.”
This procedure ensures that setting the Master Gain to the mid-position will always give a reasonable
setting for gain on all axes, even if you have more than one model using a Lemon Stabilizer or StabPLUS. You
may want to turn down Master Gain by an hour to make sure you avoid oscillation.
You may find it helpful to increase Master Gain moderately in turbulent conditions.
After you have set the gain pots and Master Gain to your liking, it’s a good idea to limit the range of travel
on channel 8 (Aux3) to prevent unpleasant surprises if the knob or slider gets moved accidentally. This can
be done using Travel on the Servo Setup menu. Some people prefer to disable Master Gain at this point by
inhibiting channel 8 (Aux3) in the Channel Assign menu. You can always reactivate the channel if you need
to do further adjustments.
Resetting the Stabilizer
Resetting Level and Alignment (Toggle during initialization)
By default, the Stabilizer PLUS uses its built-in settings when initialized, based on the assumption that the
stabilizer is mounted upright and level and accurately aligned with the flight direction. To compensate for
any variations, the stabilizer can be reset by performing a “toggle gesture” during the initialization process.
15
When the Master Gain control is set to -150% travel, gain will be zero and there will be no stabilization (anything
multiplied by zero is 0). When the control is set to 150% travel, the gain on each of the pots will be multiplied by two.
In practice, however, it is usually best to leave travel at +/-100%.

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This is also required if the stabilizer is mounted inverted or on edge (e.g., on a profile fuselage), or if the unit
is mounted not quite level. All these cases require toggling.
Toggle Gesture
Move the Stabilizer Mode switch on your transmitter back
and forth as quickly as possible through its full range for
2-3 seconds. This procedure applies to both 2- and 3-position
switches. At a minimum the stabilizer needs to see six
changes of switch position (see diagram) within 2 seconds,
but a few more changes are desirable to guarantee a
successful reset.
3-position
2-position
To reset level as seen by the stabilizer:
1. Set the model up in level flight position on the bench.
16
2. Turn on the transmitter and apply power to the stabilizer (bind plug not required if previously bound).
3. When Indicator 1 (Green/Blue) starts flashing, immediately (within 8 seconds) perform the toggle
gesture explained above, flipping the switch back and forth continuously for 2-3 seconds.
DO NOT MOVE OR DISTURB THE MODEL during the initialization period.
4. The Red LED of Indicator 2 should now come on for a few seconds. After a further wait, the Green LED
of Indicator 2 should flash four times to confirm initialization.
If you do not see this confirmation, repeat the whole process until you do. This is necessary to ensure
correct initialization. A possible reason for failure is movement of the model during initialization.
5. Power down the stabilizer
If you observe any unexpected responses from the model, on the ground or in the air, perform a Level Reset
as described above. Also, don’t forget to also reset the stick neutrals, as described in the next section, as
their setting, while not usually critical, can sometimes have an important impact on the model’s behavior.
The Stabilizer retains the values generated, even when powered down, so the procedure doesn’t need to be
repeated unless you want to adjust Autolevel attitude or you change the stabilizer's position in the plane.
If you perform this procedure, it’s REALLY important to verify that the “toggle gesture” is successful, as it
resets the Stabilizer’s orientation and Autolevel values. Be sure you see four Green flashes on the
Indicator 2 LED (near the pins). No flashes = no fly!
Resetting Stick Neutrals (Toggle after initialization)
To ensure optimum stabilizer performance, after any major adjustment of the trims or subtrims you should
use the toggle gesture (as defined above) to reset the stabilizer's values for the stick neutral positions. This
is an entirely separate process from resetting level and can be done at any time AFTER the stabilizer has
completed its initialization. During the reset, the aileron, elevator and rudder sticks and the corresponding
trims must not be moved.
With the transmitter and stabilizer ON, and leaving the sticks and trims untouched, move the Stabilizer
Mode (Gear) switch as quickly as possible back and forth for about 2 seconds.
There is no verification but the process is extremely simple and reliable.
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Some models may need to be slightly nose-up (typically 1-3°) to maintain level flight at a normal throttle setting.

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The Stabilizer PLUS performs best, especially in Autolevel mode, when trim and subtrim settings are kept to
a minimum. Where possible, use mechanical adjustments to eliminate the need for large trim offsets, then
reset the stick neutrals as described above.
Calibration of the Sensors (no action normally needed)
Calibration of the sensors is a totally separate process from resetting stabilizer level or stick neutrals.
Calibration is seldom needed; when it is, the indication is a jump in servo position on one or more axes
when the Stab is switched back and forth between OFF and Gyro (with no movement of the Stab).
The StabPLUS attempts to calibrate its sensors automatically every time it is powered up, provided the
stabilizer remains absolutely stationary, with no vibration, for 2 or 3 seconds at the beginning of the
process. No special effort is needed to enable this, unless signs of calibration error are seen.
Special Options
Stabilizer Always-ON (requires Rebind)
By default, channel 5 (Gear) is dedicated to controlling Stabilizer mode (OFF, Gyro, Autolevel), so its pins are
not generally usable for other functions. The Stabilizer Always-ON function, however, allows channel 5 to be
used to control landing gear or for other functions. Because Always-ON cannot be changed or canceled in
flight, it should normally be used only with Gyro mode. To verify the setup, it is a very good idea to fly your
model at least once with an off switch available before setting Always-ON (if you have an eight or more
channel transmitter, you can use Master Gain as an OFF control).
To enable Stabilizer Always-ON:
1. With receiver and transmitter powered down, insert a bind plug into Bind/channel 7.
2. Power up the receiver. Indicator 2 lights (Red/Green) should be flashing rapidly to signal Bind Mode.
3. Turn on the transmitter in Bind Mode (see instructions for your transmitter).
4. Wait for Indicator 1 (Green/Blue) to stop flashing and Indicator 2 (Red/Green) to show stabilizer mode.
This may take 20 seconds or more. Be patient.
5. Set the channel 5 (Gear) switch on the transmitter to Gyro mode (Green ON, Red OFF). Autolevel mode
(Red/Green alternately flashing slowly) is not recommended for use in conjunction with Always-ON.
6. Press and hold the button (>1s) until the Indicator 1 Blue LED is ON, showing that Always-ON has been
selected. In this condition, channel 5 (Gear) no longer controls stabilizer mode and can be reassigned
for another purpose.
7. Power off and remove the bind plug.
The Always-ON setting will be retained even when the stabilizer is powered off.
Note that even with Always-ON active, the toggle gesture still works to reset level or stick neutrals.

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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Mode Order and Autolevel Setting (Bind Plug on channels 4, 5, 6)
A bind plug inserted across the signal pins of channels 4, 5 and 6 will cause the
Stabilizer PLUS to use the blue/green Indicator 1 lights to display the current
Stabilization Mode Order:
•Default order: OFF/Gyro/Autolevel – Indicator 1 Green flashing
•Alternate order: OFF/Autolevel/Gyro – Indicator 1 Blue flashing
In this state, the Stabilizer uses Indicator 2 lights to signal the Autolevel setting:
•Beginner setting (default) severely limits bank and pitch angles –
Indicator 2 Green flashing
•Advanced setting gives the pilot a greater degree of control – Indicator 2 Red flashing.
17
The Mode Order and Autolevel settings can be changed as follows:
1. With the Stab PLUS powered OFF, insert a bind plug across the signal pins for channels 4, 5 and 6 (i.e.,
the last three – see picture and Annex A). Power is connected to any other available set of pins. The
transmitter is not required for this action.
2. Power up the receiver.
3. Press the stabilizer button:
•for more than 1 second to change the Stabilization Mode Order.
•for less than 1 second to change the Autolevel setting.
18
4. When the desired changes have been made, power OFF the stabilizer and remove the bind plug.
To check the settings, simply power up the stabilizer with the bind plug across channels 4, 5 and 6 and
observe the configuration of Indicator 1 and Indicator 2 lights. See above for the meaning of the lights.
The settings will be retained even when the stabilizer is powered off. To reverse a change, repeat the
procedure described above.
Hardware Reset (Bind Plug across channels 2, 3, 4)
To reset the Stabilizer PLUS to factory default settings, insert a bind plug
on the signal pins of channels 2, 3, and 4, as shown in the picture. Note
that channel 2 (Aileron) is the third set of pins from the left.
Connect the ESC, BEC or battery to any available set of pins. The
transmitter is not required.
When power is applied for a second or two, the lights on the stabilizer
will blink in sequence, indicating that all internal settings have been
returned to default. This includes any stabilizer offsets, orientation
settings, failsafe presets, mode order changes, etc.
To complete the reset, you may wish to set the stabilizer pots back to the 12 o’clock position and return all
DIP switches to OFF, but this is not required.
A good practice if you encounter unexpected behaviors from the stabilizer is to perform a hardware reset,
followed by rebinding of the stabilizer. Then start afresh with stabilizer settings.
17
For many pilots, the Beginner setting will probably seem relatively unresponsive. We suggest the use of Advanced
setting in most cases.
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To change both settings, press the button twice, once for more than 1 second and once for less than 1 second.

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Other Issues
IMPORTANT: Don't use Autolevel with Flaperons or Aileron Differential
Autolevel mode on the StabPLUS is intended to help you stay within safe limits and recover from difficult
situations. In using it, however, you must accept some limits on your options. In particular, Autolevel is
incompatible with both Flaperons and Aileron Differential.
The Flaperon function when activated causes dual servos on separate channels to lower or raise both
ailerons, thus giving a flap or spoiler effect. This action involves a significant shift in the neutral settings of
the two aileron channels, something the stabilizer in Autolevel mode cannot properly interpret. As a result,
selecting Autolevel while flaperons are deployed may cause the model to behave erratically. Hence,
flaperons must NOT be deployed when the stabilizer is in Autolevel mode.
Likewise, Aileron Differential is used to improve coordination of turns by reducing servo travel for the down-
going aileron, which limits adverse aileron drag. For example, in a right turn, 50% differential will cause the
left aileron to go DOWN only half as much as the right aileron goes UP. Unfortunately, this can conflict with
Autolevel roll correction and may cause erratic aileron response. Consequently, the differential function
must not be used in Autolevel mode.
Solutions
Flaperons can be used safely only when the StabPLUS is OFF or in Gyro mode. We have provided mixes on
RCGroups for Spektrum transmitters to ensure that Autolevel is not available when flaperons are active.
19
There’s no problem using two servos on separate channels in Dual Aileron Wing Type, or a Y-cable driving
both servos in Normal Wing Type. It’s when the Wing Type is set to Flaperons that special care is needed.
Similarly, Differential can be blocked in Autolevel mode but allowed in OFF of Gyro mode. To do this, use
the same three-position switch to select Differential as you use for Stabilizer Mode; simply ensure that the
Differential amount corresponding to the switch position for Autolevel (normally Position 2) is set to 0%.
Note that Autolevel provides Gyro-type stabilization on the yaw (rudder) axis, thus helping to ensure
coordinated turns, even without aileron differential. In addition, some models might benefit from a small
amount of aileron-to-rudder mixing, either full-time or only when in Autolevel mode. Alternatively, “old-
fashioned” mechanical aileron differential is very effective and is often easy to incorporate by offsetting
either the servo arms or the aileron control horns.
Using Other Mixes with Autolevel
While mixes other than Flaperon and Aileron Differential don’t generally clash directly with Autolevel, they
should be used with care because the combination can cause significant unexpected reactions. For example,
a throttle-to-elevator mix intended to prevent excessive climb at high throttle may work correctly in Gyro
mode but cause the model to dive suddenly when switched to Autolevel. This is because Autolevel is
already set to keep the model flying level, so the down elevator generated by the mix at high throttle is
interpreted as a command to push the nose down further. A high speed dive is the result.
Some mixes are NOT allowed in Autolevel mode. The technique to prevent use of Flaperons in Autolevel
mode explained in the footnote above can be adapted to any mix to achieve this.
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For details on these mixes, please go to the Lemon Stabilizer Plus Configurations thread.

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IMPORTANT: Don’t Use Elevon and V-tail Mixing in the Transmitter
Like other stabilizers, the StabPLUS absolutely requires that any elevon (delta wing) or V-tail mixing MUST
take place in the stabilizer and NOT in the transmitter. Use of any such transmitter mixing will almost
invariably cause a crash immediately after takeoff! This is true even when the stab is turned OFF by the
transmitter, using channel 5 (Gear). Even in this case, Elevon and V-tail mixing MUST be controlled by
switches J4 and J5, as shown in the illustration on page 4.
Use of elevon or V-tail mixing in the transmitter is permitted only if stabilization is permanently turned OFF
at the stabilizer(i.e., switches J4 and J5 are OFF). The StabPLUS then functions as a plain 7-channel receiver.
Alignment and Mounting of the StabPLUS
The Lemon Stabilizer PLUS MUST be mounted in alignment with the flight axis of the model. It can be
mounted upright, inverted or on either edge. Lemon recommend that the servo connectors should be to
the REAR of the model, although some users report successful operation with the pins forward.
Only if the StabPLUS is mounted flat on the floor can the built-in default values be used for level. If mounted
in any other orientation, or if fine tuning of stabilizer level is needed, the Reset “toggling” process described
earlier (page 11) must be used. For best results with Autolevel, the unit should be located close to the
center of gravity of the model. These issues are discussed in more detail in the Reference Guide.
Mounting
All stabilizers must be protected from vibration and shock, yet attached securely enough to follow the
movements of the model without wobbling or coming loose. The double-sided mounting tape provided
with the Lemon StabPLUS offers the simplest solution. Use it to attach the stabilizer in the appropriate
attitude to a flat surface in the model. Make sure the surface is clean, the attachment is secure and the
stabilizer case is not touching any part of the model. Good quality servo-mounting tape or 3M (Scotch)
Permanent Outdoor Mounting Tape is also suitable for this purpose. Do not use the common indoor white
foam mounting tapes for this purpose.
Mounting with adhesive tape can make subsequent removal of the unit difficult. Accordingly, Velcro®-type
tape can be used. Cover the whole bottom of the stabilizer with the fuzzy (loop) side of the material. Use a
patch of the hook-side material at least as big as the case to avoid the possibility of the stabilizer wobbling.
Be careful when removing the stabilizer , as the case is only held together by two small screws and two
pegs. To provide reinforcement, it’s a good idea to apply clear transparent tape to the case sides.
These methods are suitable for electric-powered models, but may not provide sufficient isolation in the
harsher environment of a fuel-powered (IC) model. For further information, see the Reference Guide.
Minimizing Vibration
Autolevel stabilizers are particularly susceptible to vibration. One symptom is deviation from level flight over
time in Autolevel mode. It is therefore very important, even for an electric model with a properly mounted
stabilizer, to eliminate sources of vibration. Balance the propeller and check for any out-of-true running of
the motor shaft or bearings. A well-balanced electric model should show no noticeable vibration in any part
of its speed range.

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Annexes
Annex A: What do those tiny cryptic letters on the label mean?
Annex B: Stabilizer Mode Settings
The inputs required by the Stabilizer PLUS on channel 5 (Gear) do not need to be exact. The following ranges
will be recognized as defining the three Stabilization modes:
•Any value below -36% (pulse length 1356us) will put the unit into Autolevel mode.
•Any value between -35% (1360us) and +35% (1640us) will invoke Gyro mode.
•Any value above +36% (1644us) will turn the Stabilizer OFF.
Annex C: Setting up a Current Generation Spektrum Transmitter for the StabPLUS
The following should apply with only minor adjustments to such recent transmitters as the DX6, DX6e, DX7s,
DX8G2, DX9, and DX18 (not DX6i, DX7, DX8). Updating to the latest firmware is recommended.
1. Select a new model (or do a reset on a previously used model memory) and name it appropriately.
2. For a single aileron servo, or two servos on a Y-cable, set Aircraft Type to Normal Wing, Normal Tail.
For two servos on separate channels (2 and 6), set Aircraft Type to Dual Aileron.
3. Under Channel Assign, leave Rx Port Assignments as is.
4. Under Channel Assign, (second page), set Channel Input Config to a suitable 3-way switch (such as D)
for channel 5 (Gear) and to RKnb for channel 8 (Aux3), if available. Inhibit any unused channels.
5. In Trim Setup, set Throttle to 0 to disable throttle trim.
6. Set up D/R and Expo as required on a suitable switch.
7. Set up Throttle Cut to -100% on a suitable switch (most commonly H).
Further examples of transmitter setups are provided in the Lemon Stabilizer Plus Configurations thread.

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Annex D: Using a Two-Position Switch to Control Stabilization
Many older transmitters, such as the DX6i have only a two-position switch (-100/100) for channel 5 (Gear).
One way to deal with this limitation is to set the Mode Order to allow one desired type of stabilization. In
the default Mode Order (OFF/Gyro/Autolevel), a two-position switch will select OFF or Autolevel. The
alternative order (OFF/Autolevel/Gyro) will allow the switch to select OFF or Gyro.
Another way is to reduce the switch travel (end point) on the -100% side to 0%. The switch will then deliver
100% (Autolevel mode) or 0% (Gyro mode). It is important to recognize that this provides no way to turn
stabilization OFF, unless the transmitter supports Master Gain on channel 8.
Annex E: Setting up a DX6i for the StabPLUS
The Spektrum DX6i is no longer available, but as one of the most popular transmitters of recent years there
are still vast numbers of them in use. The DX6i has two-position switches on channel 5 (Gear/F-Mode) and
channel 6 (Flap/Gyro), as well as on Mix, Ail D/R and Elev D/R. It has two programmable mixes.
In addition to the methods explained above, the DX6i's switch limitations can be worked around by using
the Gear switch and the Mix switch together to simulate a three-position switch. The following mix is used:
MIX 1
GEAR →GEAR ACT
RATE D 0% U –100%
SW MIX TRIM INH
Note that the Elevator D/R switch can be substituted for Mix.
If the GEAR channel is set to Reverse, this mix will produce -100%/0%/100% output, functioning as follows:
•Gear switch in Position 0: Gives Stabilization OFF (100%) for either position of the Mix switch.
•Gear switch in Position 1:
−Mix switch in Position 0 gives Autolevel mode (-100%).
−Mix switch in Position 1 gives Gyro mode (0%).
Since the StabPLUS is usually ON in flight, this allows easy switching between Gyro and Autolevel.
If the GEAR channel is left in Normal, the mix will have the following result:
•Gear switch in Position 0: Gives Autolevel (-100%) for either position of the Mix switch.
•Gear switch in Position 1:
−Mix switch in Position 0 gives OFF (100%).
−Mix switch in Position 1 gives Gyro mode (0%).
Thus Autolevel can be reached easily from OFF or Gyro, desirable if AL is used for Panic Recovery.
Which way you set it up is your choice.
Annex F: Using Channel 7 on the Lemon Stabilizer (v4 and v4.5) and StabPLUS
Current versions of the Lemon Stabilizer and StabPLUS allow channel 7 (Aux2) to be used as a normal servo
output, once the receiver has been bound.
Most servos work well when attached to channel 7, which also serves as the Bind slot. However, a few
servos, and many electric retract units, have sufficiently low input resistance (impedance) that they can be
seen by the receiver as a bind plug (a connection between the signal and ground pins). If this is the case,
then every time you power up the receiver it will go into bind mode.
There are a number of ways to overcome this problem:

Lemon RX Stabilizer PLUS Receiver – Essential Instructions v.1.5
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1) Do not use channel 7 for retracts. Instead, assign electric retracts to channel 6 and use channel 7 for a
function such as flaps (few servos cause the problem).
2) Plug in the channel 7 connector after the receiver has powered up (usually inconvenient).
3) Put a small switch in the signal lead of the device on channel 7 and only switch ON after power up (still
inconvenient but better than 2 above).
4) Add a resistor in the signal lead for channel 7. This increases the resistance so the receiver does not go
into bind mode. It does not normally affect the operation of either retracts or a servo on that channel
because the signal current is very small. A value of 1000 Ohms (1k) is a good starting point. The lower the
value that reliably prevents binding the better.
An example of a problematic model is the Dynam P61, where both the retracts and the servos on channel 7
will cause the receiver to go into bind on application of power. One user on RCGroups reported solving this
completely with a 680 Ohm resistor in the channel 7 signal wire.
As far as is known, the issue affects versions V4 and v4.5 of the regular Stabilizer. It does not normally occur
with the Stabilizer PLUS. Versions of the regular Stabilizer prior to v4 do not allow channel 7 to be used at all
when the receiver is in stabilized mode.
Lemon Stab Plus Essential Instructions 2022 v.1.5.docx Revised 2022-Feb 28