Power Switch: Graupner MX-16 iFS - 2010/04

54 MODEL AVIATION
GREG GIMLICK
Power Switch: Graupner MX-16 iFS
The top right has a three-position and a two-position
switch, along with another increase/decrease button and
on/off button designated SW4/PB8 (switch 4, and
program button 8).
Top left section of the radio has two two-position
switches, along with an analog dial and increase/decrease
buttons that are all assignable. This would also be an
excellent radio for RC boats.
An eight-channel,intelligent
Frequency Select
radio system
Duration RC sailplane pilots
should appreciate that the MX-
16 is equipped with a 2000 mAh,
9.6-volt NiMH transmitter
battery that should last for hours
of flying. Michael Ramsey photo.
THE NEW GRAUPNER MX-16 iFS offers you a
way to take part in the 2.4 GHz revolution for a
reasonable price and offers programmability that may
shock you. Although it might not be a complete shift
in paradigm, it is different from most radios available
in the US today.
This eight-channel system comes out of the box
with four defined functions assigned to the two gimbal
sticks. Beyond that, you’re on your own to define the
other switches and functions.
For those of us coming from radios such as the
Multiplex Evo, this is a gift. We’re used to being able
to assign functions to whatever switch or dial we
want, and this feature of the MX-16 iFS feeds that
desire the way we like.
If you’re coming from radio brands that have
predefined controls and switches, it might be a bit
confusing at first. Once you work your way through
the manual and realize the benefits of this, you’ll
never go back.
The Graupner case might be familiar to those who
have used a JR radio, and that’s because it’s the
The Graupner MX-16 arrives as most new radio systems do: foam encased
with a colorful box. A compatible charger is required. The manual is included
in both paper and CD form.
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:26 AM Page 54
April 2010 55
Photos by the author except as noted
Left: The receiver default channel
assignments are unique in that the throttle
is in the channel 6 position and collective is
at channel 1, grouping the CCPM servos
close together.
From the start-up screen, pressing down on the roller will show
servo positions. This window indicates whether or not dual
elevator and/or dual aileron servos are correctly linked.
The MX-16’s insides. The only time you would need to go in here is
to change the ratcheting on the throttle stick or spring tension of the
others. Greg uses a smooth, noncentering throttle for both
helicopters and airplanes.
Above: The author’s “breadboard” setup
allows easy experimentation on the bench
while learning the radio. He used this setup
for the Fw 190 when testing was complete.
Pressing the “ENTER” button once brings up the main
programming window menu. Actuate the roller right or left to
highlight the submenu, and then press the roller to access.
Pluses and Minuses
+
• Assignable switches and controls.
• Easy-to-read screen.
• Plenty of predefined mixes.
• Adjustable modes to comply with
international travel.
• Easy to program.
• Rock-solid 2.4 GHz link and response.
-
• Only 12 model memories.
• No transmitter charger (wall wart).
Transmitter Specifications
Frequency band: 2.400-2.4835 GHz
Control functions: Eight
Servo resolution: 65,536 steps (16-bit)
Temperature range: -25 degrees
Celsius to +125 degrees Celsius
Operating voltage: 9.6-12.4
Battery: 2000 mAh, 9.6-volt NiMH
pack
Current drain (approximately):
185 mA
Dimensions (approximately): 195
x 190 x 85 mm
Weight (approximately): 850
grams including transmitter battery
XR-16 iFS Receiver Specifications
Operating voltage: 2.9-25
Current drain (approximately):
70 mA
Frequency band: 2.4-2.4835 GHz
Servo resolution: 65,536 steps (16-
bit)
Servo signal accuracy: ±10 ns
Aerial length (approximately): 3cm,
completely enclosed in receiver case
Servo functions: Eight
Temperature range: -15 degrees
Celsius to +55 degrees Celsius
Dimensions (approximately): 54 x
29 x 14 mm
Weight (approximately): 19 grams
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:28 AM Page 55
56 MODEL AVIATION
Greg set up 30% aileron differential for testing the MX-16 radio in
his Kyosho Fw 190. Besides dual rates, flight-mode (called phases)
options are available.
Settings for dual rate and exponential, also showing switch
assignment and position. Actuation of the assigned switches
discloses the programmed settings for that particular position.
The ei ght-channe l XPS receiver mus t be
i n st al le d wi th i ts a nte n na clear of dense
obstr uc tion, such a s a bat te ry o r landing
gear. Its installation in the Fw 190 is neat.
The six-channel-function Focke-Wulf Fw 190 worked extremely well with the MX-16
radio system.
• Bidirectional communication between
transmitter and receiver.
• Tremendously fast transmission rate for
extremely fast system response, and 16-bit
encoding for exceptionally high resolution
of 65,536 steps per control channel.
• Virtual elimination of interference caused
by motors, servos, and electrical-charge
effects (metal-to-metal noise).
• Removable folding stub aerial antenna.
• Methods of operation and programming
based on proven concepts of the MC-19 to
MC-24 Graupner radios.
• High-contrast graphic screen for control of
setup parameters, operating modes, timers,
and operating voltage.
• Eight control functions with convenient,
simplified method of assigning controls for
auxiliary functions such as switches and
proportional controls.
• Twelve model memories for storing all
model-specific programming and setup
parameters.
• Transmitter case includes four switches
(one of which is a three-position type), one
momentary button, one analog control, two
digital controls, all of which are freely
programmable for total flexibility.
• Function encoder with rotary cylinder and
three momentary buttons for programming
and accurate setup.
• When you change modes, all affected
settings are switched at the same time.
• Graphical servo display provides a
straightforward overview of servo setup and
a swift method of checking servo travels.
• Receiver output swap.
• Fixed-wing menu for: 1 AIL, 2 AIL, 2
AIL + 2 FLAP, V-tail, delta/flying wing,
two elevator servos.
• Fixed-wing mixer: diffail, diffflaps,
ailrud, ailflaps, brakeelev, brakeflap,
brakeail, elevflap, elevail, flapelev,
flapail, and diff. reduction.
• Helicopter menu: 1-point, 2-point, 3-point,
and 4-point linkages (1 servo, 2 servo, 3sv
[2 roll], 3sv [2 nick pitch axis]), 4 SV (90°).
• Servo travel adjustment ±150% for all
servo channels, variable for each endpoint
separately (Single Side Servo Throw).
• Subtrim for fine-tuning the neutral position
of all servos.
• Servo reverse, programmable for all
servos.
• EXPO/DUAL-RATE system, separately
variable, can be switched in flight.
• Mixer functions: Aileron differential
mixer, butterfly mixer, flaperon mixer, and
three freely programmable mixers.
• Programmable Fail-Safe function in
receiver with “hold-mode” and “move to
preset position” function, variable separately
for each servo channel.
• Stopwatch/countdown timer with alarm
function.
The author used a Heli-Max MX450 to
test the MX-16’s helicopter programming.
The XPS tag is handy for depressing the
receiver “link” button. Photos on this
page by Michael Ramsey.
A six-channel XPS park-range receiver is
nestled neatly between the helicopter side
frames. The 6-gram receiver’s antenna is
totally internal.
XPS offers three compatible receivers for the MX-16 radio: a standard eight-channel full
range (left), micro six-channel full range (center), and eight-channel carbon-fuselage version.
Program Features
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:33 AM Page 56
same—complete with rotary cylinder for
easy programming. That’s where the
similarity ends.
Graupner utilizes 2.4 GHz intelligentfrequency-
select technology, to give its
bidirectional receiver a rock-solid link.
That makes future expansion of
capabilities and telemetry possible.
Graupner employs a full-time frequencyhopping
mode as the default that can be
changed to adaptive if desired.
The system comes with the MX-16
transmitter and one eight-channel
receiver (no servos, charger, or receiver
batterypack), for a retail price of $299.
You’ll need to get a charger or use one
of your fast chargers with an appropriate
connector for the 2000 mAh, 9.6-volt
transmitter battery.
If you have a JR wall wart charger,
you can use it. Since many of us seem to
have dozens of chargers and seldom use
the receiver packs or servos that come
with radio systems, I see this as a bonus
and not an omission.
From the Beginning: When you turn on
the radio, you go through the normal
steps of setting up a new model, the same
as with most radios. Some differences
are slight but significant.
You can easily select one of four
transmitter modes instead of having to
order one set up that way from the
manufacturer. Most US fliers use Mode
2, but plenty of old RC Aerobatics pilots
still want Mode 1, and that’s a simple
menu selection. Modes 3 and 4 are also
available.
Stick length is adjustable, and you
can change the self-neutralizing or spring
tension by opening the back of the
transmitter case and adjusting the screws
and springs. You adjust the contrast of
the digital screen using the rotary
cylinder.
Pushing the “Enter” button takes you
to the main menu, and the rotary cylinder
will take you through the choices. If you
get confused or make an error, it’s easy
to back out; hitting the “ESC” button
will take you back to the main menu. The
“Clear” button zeroes out a setting when
selected without having to spin a wheel
to get back to zero.
When I learn a new radio, I like to
“breadboard” it. I set up the receiver and
plug servos into each slot while laying
them out on a large sheet of paper, on
which I label each servo’s purpose. This
allows me to work my way through each
setup step and actually see what is
happening on the receiver end.
The “Base Menu” sets up the primary
settings for the aircraft. You select stick
mode, tail type, aileron/flap type, clock
style, and flight phases here. The wheel
lets you scroll through the choices for
each and sets up the radio for using two
aileron servos, etc., “automagically.”
There is a setting for “receiver out.”
This allows you to reassign channel
outputs to the receiver channel numbers
you want. Most fliers might not use this
feature, but it’s nice to have for special
applications. The default is, channel 1
speaks to channel 1 of the receiver and
so on, but you could tell channel 1 to
speak to channels 1, 2, and 3 on the
receiver.
After leaving the Base Menu, you can
proceed to the Control Settings, where
you can define which switches you want
to control which servos beyond the
preprogrammed ones. You can assign
them to whatever switches you want. The
great thing about this is that if you don’t
like where your flight mode or gyro
switches are, you can change them to fit
your likes and dislikes.
Now head to the Servo Settings menu.
Here you can adjust your subtrim
centering, reversal, and travel
percentage. Furthermore, you can select
whether or not you want your travel on
each side of neutral to be equal
(symmetrical) or asymmetrical.
From the Servo Settings menu, it
makes sense to look at dual rates and
exponential functions. Again, you can
assign the switch you want to the dual
rate functions. You can make one switch
handle both aileron and elevator dual
rates if you want. You can assign the
same for rudder.
Phase Trim functions are
exceptionally handy for advanced
airplanes and helicopters. You can define
three flight phases here for such things as
takeoff, speed, thermal, landing,
aerobatics, tow, etc. With the simple flip
of a switch, you can go into a
preprogrammed landing mode without
having to make changes during the flight.
Helicopter fliers, pay close attention
to the channel assignments; they are
different from the airplane programming.
Well, two channels are different. The
throttle and collective channels are
swapped.
That is likely to keep the aileron,
elevator, and cyclic servos grouped
closely, because they are prevalently linked
via CCPM mechanics. Once that difference
is overcome, the MX-16 is as comfortable
as on the airplane side to program.
Mixes: The MX-16 takes the guesswork
out of setting mixes. There are several
predefined mixes for helicopter and
fixed-wing aircraft. This feature is most
helpful, because the work is done for
you. You only have to select the mixes
you want from the menu and set the
percentage of mix you want.
The screens are self-explanatory, but
let’s say that you want 15% elevator
when you throw the flaps full down.
Select the “brake—elevator” option and
choose the switch that controls your flaps
(here referred to as brakes). If you want
some rudder added automatically when
you make a turn using ailerons, select the
“ail-rud” choice and set the percentage.
Another biggie is differential. With
the MX-16, there is a predefined mix
selection for that. You don’t have to do
anything mechanically in the model’s
wing; you merely select the differential
mix and dial in the percentage of
differential you want. That’s it.
Differential isn’t dependent upon the
mechanical linkage setup. Positive or
58 MODEL AVIATION
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:35 AM Page 58
60 MODEL AVIATION
negative values can be given to the mix so
that differential in the correct direction
can be set.
If you’re a sailplane pilot, you will love
all of the predefined mixes to help set up
crow, butterfly, brakes, etc., with the
ability to set differential flaps and reduced
differential. These are predefined, so all
you have to do is set the switches and
percentage. The majority of the work is
done for you.
The coup de grâce is the three free
mixes left for you to define however you
want them. Few radios allocate this many,
and the MX-16 iFS is the only one in its
price range I’ve seen that provides you
with three.
Few pilots will ever use the free mixes,
because so many are already defined. But
for those who experiment and design
helicopters or airplanes with controls
outside the normal realm of things, it’s a
godsend.
Model Memories: The transmitter has
memory to keep 12 aircraft programmed
all the time. They can be a mix of any
type, and the program mixes, etc. are kept
in each memory.
Every memory is a clean slate (in
Mode 1). So if you’re a Mode 2 person, as
I am, there’s a time-saving trick.
Select the mode you fly in the first
model memory, and then copy that model
to every model slot. If you fly helicopters,
you’ll also change the pitch-movement
direction. (Low pitch default is with the
stick reversed—full forward.)
Regardless of model type, an alarm for
safety will sound if the throttle is above
idle position when the transmitter is
turned on. Likewise, an alarm will sound
in the helicopter mode if the idle-up
switch is out of the normal mode, to help
prevent a hot start. There are three idle-up
choices.
The Receiver: The MX-16 iFS comes
with an eight-channel receiver, utilizing a
single stub antenna on the top. Each plug
is labeled with its number, and the
receiver arrives bound to the transmitter.
You can add more receivers and simply
follow the manual’s simple binding
instructions.
Once bound, the link is acquired
extremely fast. In advanced programming
modes, you can change many of the
receiver’s parameters, such as hopping
mode, etc. These must coincide with the
mode set in the transmitter.
One feature of the receiver that is
helpful in diagnosing issues of your setup
is the glowing orange LED. If that turns
from green to orange during operation, it
indicates that the voltage has dropped
below acceptable levels during the flight
or test run. Do not operate the airplane or
helicopter until you have diagnosed and
corrected this issue.
Most occurrences can be traced to not
using a large enough receiver battery or
an insufficient BEC unit. It requires only
a voltage dip below 4.4 longer than 25ms
to trigger the low-voltage warning.
When installing your receiver, ensure
that no wires can make contact or come
within close proximity of the receiver
antenna. This can cause interference,
regardless of the type of system in use.
People tend to think that the switch to
2.4 GHz eliminated all interference
problems, but you must still take care
when installing wires around the receiver
antenna. Secure them and you will have
no problems.
Because the MX-16 uses Xtreme
Power Systems’ (XPS’s) iFS radio
technology, any XPS receiver will work
with the Graupner radio. Besides the
standard eight-channel XtremeLink
receiver that is identical to the XR-16
included with the transmitter, the eightchannel
sailplane receiver for lighterweight
(low vibration) applications is now
available. The sailplane receiver is
equipped with an antenna extension, so
that the signal can be retrieved outside
carbon-fiber fuselages.
For park flyers, a great choice is the
six-channel XtremeLink receiver, which is
suitable for shorter range applications; it
doesn’t even have an external antenna. All
XPS receivers are licensed by the FCC.
An International Radio: I call it that,
because if you travel around the world on
business and like to carry a model with
you for leisure, you can set the MX-16
iFS for whatever country requirements
you encounter. It arrives programmed to
the US standard, so you’re set if you
don’t leave the country.
If you do travel abroad, you can reset
the output and hopping modes to be legal
elsewhere by going into the receiver’s
and transmitter’s advanced programming
modes, as described in the manual. This
is a big plus for those who travel to
international events.
The bottom line for me is how a system
performs in the air and how easy it is to
set up. In both cases, the MX-16 came
out a winner. Setup is simple, and the
predefined mixes and settings are all that
are needed in 90% of the cases. The link
between the radio and the model is solid,
even in a crowded environment.
At the field, using a foam trainer, and
in a controlled environment, I shut off the
transmitter while the airplane was in
level cruise, roughly 50 feet high, and
then turned the transmitter back on. As
soon as I did, the model went into the
fail-safe mode and regained control.
That action was quick and barely
noticeable. I don’t recommend that you
test your system this way, but under
controlled conditions it proved that the
solid link is rapidly restored.
If I had one wish, it would be that the
MX-16 iFS held more than 12 models in
memory. If that’s my only complaint—
and it is—the bottom line is that this radio
is a winner. MA
Greg Gimlick
[email protected]
Manufacturer/Distributor:
Graupner/Xtreme Power Systems
2440 Kiowa Blvd. N. #102
Lake Havasu City AZ 86403
[email protected]
www.xtremepowersystems.net
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:36 AM Page 60

54 MODEL AVIATION
GREG GIMLICK
Power Switch: Graupner MX-16 iFS
The top right has a three-position and a two-position
switch, along with another increase/decrease button and
on/off button designated SW4/PB8 (switch 4, and
program button 8).
Top left section of the radio has two two-position
switches, along with an analog dial and increase/decrease
buttons that are all assignable. This would also be an
excellent radio for RC boats.
An eight-channel,intelligent
Frequency Select
radio system
Duration RC sailplane pilots
should appreciate that the MX-
16 is equipped with a 2000 mAh,
9.6-volt NiMH transmitter
battery that should last for hours
of flying. Michael Ramsey photo.
THE NEW GRAUPNER MX-16 iFS offers you a
way to take part in the 2.4 GHz revolution for a
reasonable price and offers programmability that may
shock you. Although it might not be a complete shift
in paradigm, it is different from most radios available
in the US today.
This eight-channel system comes out of the box
with four defined functions assigned to the two gimbal
sticks. Beyond that, you’re on your own to define the
other switches and functions.
For those of us coming from radios such as the
Multiplex Evo, this is a gift. We’re used to being able
to assign functions to whatever switch or dial we
want, and this feature of the MX-16 iFS feeds that
desire the way we like.
If you’re coming from radio brands that have
predefined controls and switches, it might be a bit
confusing at first. Once you work your way through
the manual and realize the benefits of this, you’ll
never go back.
The Graupner case might be familiar to those who
have used a JR radio, and that’s because it’s the
The Graupner MX-16 arrives as most new radio systems do: foam encased
with a colorful box. A compatible charger is required. The manual is included
in both paper and CD form.
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:26 AM Page 54
April 2010 55
Photos by the author except as noted
Left: The receiver default channel
assignments are unique in that the throttle
is in the channel 6 position and collective is
at channel 1, grouping the CCPM servos
close together.
From the start-up screen, pressing down on the roller will show
servo positions. This window indicates whether or not dual
elevator and/or dual aileron servos are correctly linked.
The MX-16’s insides. The only time you would need to go in here is
to change the ratcheting on the throttle stick or spring tension of the
others. Greg uses a smooth, noncentering throttle for both
helicopters and airplanes.
Above: The author’s “breadboard” setup
allows easy experimentation on the bench
while learning the radio. He used this setup
for the Fw 190 when testing was complete.
Pressing the “ENTER” button once brings up the main
programming window menu. Actuate the roller right or left to
highlight the submenu, and then press the roller to access.
Pluses and Minuses
+
• Assignable switches and controls.
• Easy-to-read screen.
• Plenty of predefined mixes.
• Adjustable modes to comply with
international travel.
• Easy to program.
• Rock-solid 2.4 GHz link and response.
-
• Only 12 model memories.
• No transmitter charger (wall wart).
Transmitter Specifications
Frequency band: 2.400-2.4835 GHz
Control functions: Eight
Servo resolution: 65,536 steps (16-bit)
Temperature range: -25 degrees
Celsius to +125 degrees Celsius
Operating voltage: 9.6-12.4
Battery: 2000 mAh, 9.6-volt NiMH
pack
Current drain (approximately):
185 mA
Dimensions (approximately): 195
x 190 x 85 mm
Weight (approximately): 850
grams including transmitter battery
XR-16 iFS Receiver Specifications
Operating voltage: 2.9-25
Current drain (approximately):
70 mA
Frequency band: 2.4-2.4835 GHz
Servo resolution: 65,536 steps (16-
bit)
Servo signal accuracy: ±10 ns
Aerial length (approximately): 3cm,
completely enclosed in receiver case
Servo functions: Eight
Temperature range: -15 degrees
Celsius to +55 degrees Celsius
Dimensions (approximately): 54 x
29 x 14 mm
Weight (approximately): 19 grams
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:28 AM Page 55
56 MODEL AVIATION
Greg set up 30% aileron differential for testing the MX-16 radio in
his Kyosho Fw 190. Besides dual rates, flight-mode (called phases)
options are available.
Settings for dual rate and exponential, also showing switch
assignment and position. Actuation of the assigned switches
discloses the programmed settings for that particular position.
The ei ght-channe l XPS receiver mus t be
i n st al le d wi th i ts a nte n na clear of dense
obstr uc tion, such a s a bat te ry o r landing
gear. Its installation in the Fw 190 is neat.
The six-channel-function Focke-Wulf Fw 190 worked extremely well with the MX-16
radio system.
• Bidirectional communication between
transmitter and receiver.
• Tremendously fast transmission rate for
extremely fast system response, and 16-bit
encoding for exceptionally high resolution
of 65,536 steps per control channel.
• Virtual elimination of interference caused
by motors, servos, and electrical-charge
effects (metal-to-metal noise).
• Removable folding stub aerial antenna.
• Methods of operation and programming
based on proven concepts of the MC-19 to
MC-24 Graupner radios.
• High-contrast graphic screen for control of
setup parameters, operating modes, timers,
and operating voltage.
• Eight control functions with convenient,
simplified method of assigning controls for
auxiliary functions such as switches and
proportional controls.
• Twelve model memories for storing all
model-specific programming and setup
parameters.
• Transmitter case includes four switches
(one of which is a three-position type), one
momentary button, one analog control, two
digital controls, all of which are freely
programmable for total flexibility.
• Function encoder with rotary cylinder and
three momentary buttons for programming
and accurate setup.
• When you change modes, all affected
settings are switched at the same time.
• Graphical servo display provides a
straightforward overview of servo setup and
a swift method of checking servo travels.
• Receiver output swap.
• Fixed-wing menu for: 1 AIL, 2 AIL, 2
AIL + 2 FLAP, V-tail, delta/flying wing,
two elevator servos.
• Fixed-wing mixer: diffail, diffflaps,
ailrud, ailflaps, brakeelev, brakeflap,
brakeail, elevflap, elevail, flapelev,
flapail, and diff. reduction.
• Helicopter menu: 1-point, 2-point, 3-point,
and 4-point linkages (1 servo, 2 servo, 3sv
[2 roll], 3sv [2 nick pitch axis]), 4 SV (90°).
• Servo travel adjustment ±150% for all
servo channels, variable for each endpoint
separately (Single Side Servo Throw).
• Subtrim for fine-tuning the neutral position
of all servos.
• Servo reverse, programmable for all
servos.
• EXPO/DUAL-RATE system, separately
variable, can be switched in flight.
• Mixer functions: Aileron differential
mixer, butterfly mixer, flaperon mixer, and
three freely programmable mixers.
• Programmable Fail-Safe function in
receiver with “hold-mode” and “move to
preset position” function, variable separately
for each servo channel.
• Stopwatch/countdown timer with alarm
function.
The author used a Heli-Max MX450 to
test the MX-16’s helicopter programming.
The XPS tag is handy for depressing the
receiver “link” button. Photos on this
page by Michael Ramsey.
A six-channel XPS park-range receiver is
nestled neatly between the helicopter side
frames. The 6-gram receiver’s antenna is
totally internal.
XPS offers three compatible receivers for the MX-16 radio: a standard eight-channel full
range (left), micro six-channel full range (center), and eight-channel carbon-fuselage version.
Program Features
04sig2.QXD_00MSTRPG.QXD 2/23/10 9:33 AM Page 56
same—complete with rotary cylinder for
easy programming. That’s where the
similarity ends.
Graupner utilizes 2.4 GHz intelligentfrequency-
select technology, to give its
bidirectional receiver a rock-solid link.
That makes future expansion of
capabilities and telemetry possible.
Graupner employs a full-time frequencyhopping
mode as the default that can be
changed to adaptive if desired.
The system comes with the MX-16
transmitter and one eight-channel
receiver (no servos, charger, or receiver
batterypack), for a retail price of $299.
You’ll need to get a charger or use one
of your fast chargers with an appropriate
connector for the 2000 mAh, 9.6-volt
transmitter battery.
If you have a JR wall wart charger,
you can use it. Since many of us seem to
have dozens of chargers and seldom use
the receiver packs or servos that come
with radio systems, I see this as a bonus
and not an omission.
From the Beginning: When you turn on
the radio, you go through the normal
steps of setting up a new model, the same
as with most radios. Some differences
are slight but significant.
You can easily select one of four
transmitter modes instead of having to
order one set up that way from the
manufacturer. Most US fliers use Mode
2, but plenty of old RC Aerobatics pilots
still want Mode 1, and that’s a simple
menu selection. Modes 3 and 4 are also
available.
Stick length is adjustable, and you
can change the self-neutralizing or spring
tension by opening the back of the
transmitter case and adjusting the screws
and springs. You adjust the contrast of
the digital screen using the rotary
cylinder.
Pushing the “Enter” button takes you
to the main menu, and the rotary cylinder
will take you through the choices. If you
get confused or make an error, it’s easy
to back out; hitting the “ESC” button
will take you back to the main menu. The
“Clear” button zeroes out a setting when
selected without having to spin a wheel
to get back to zero.
When I learn a new radio, I like to
“breadboard” it. I set up the receiver and
plug servos into each slot while laying
them out on a large sheet of paper, on
which I label each servo’s purpose. This
allows me to work my way through each
setup step and actually see what is
happening on the receiver end.
The “Base Menu” sets up the primary
settings for the aircraft. You select stick
mode, tail type, aileron/flap type, clock
style, and flight phases here. The wheel
lets you scroll through the choices for
each and sets up the radio for using two
aileron servos, etc., “automagically.”
There is a setting for “receiver out.”
This allows you to reassign channel
outputs to the receiver channel numbers
you want. Most fliers might not use this
feature, but it’s nice to have for special
applications. The default is, channel 1
speaks to channel 1 of the receiver and
so on, but you could tell channel 1 to
speak to channels 1, 2, and 3 on the
receiver.
After leaving the Base Menu, you can
proceed to the Control Settings, where
you can define which switches you want
to control which servos beyond the
preprogrammed ones. You can assign
them to whatever switches you want. The
great thing about this is that if you don’t
like where your flight mode or gyro
switches are, you can change them to fit
your likes and dislikes.
Now head to the Servo Settings menu.
Here you can adjust your subtrim
centering, reversal, and travel
percentage. Furthermore, you can select
whether or not you want your travel on
each side of neutral to be equal
(symmetrical) or asymmetrical.
From the Servo Settings menu, it
makes sense to look at dual rates and
exponential functions. Again, you can
assign the switch you want to the dual
rate functions. You can make one switch
handle both aileron and elevator dual
rates if you want. You can assign the
same for rudder.
Phase Trim functions are
exceptionally handy for advanced
airplanes and helicopters. You can define
three flight phases here for such things as
takeoff, speed, thermal, landing,
aerobatics, tow, etc. With the simple flip
of a switch, you can go into a
preprogrammed landing mode without
having to make changes during the flight.
Helicopter fliers, pay close attention
to the channel assignments; they are
different from the airplane programming.
Well, two channels are different. The
throttle and collective channels are
swapped.
That is likely to keep the aileron,
elevator, and cyclic servos grouped
closely, because they are prevalently linked
via CCPM mechanics. Once that difference
is overcome, the MX-16 is as comfortable
as on the airplane side to program.
Mixes: The MX-16 takes the guesswork
out of setting mixes. There are several
predefined mixes for helicopter and
fixed-wing aircraft. This feature is most
helpful, because the work is done for
you. You only have to select the mixes
you want from the menu and set the
percentage of mix you want.
The screens are self-explanatory, but
let’s say that you want 15% elevator
when you throw the flaps full down.
Select the “brake—elevator” option and
choose the switch that controls your flaps
(here referred to as brakes). If you want
some rudder added automatically when
you make a turn using ailerons, select the
“ail-rud” choice and set the percentage.
Another biggie is differential. With
the MX-16, there is a predefined mix
selection for that. You don’t have to do
anything mechanically in the model’s
wing; you merely select the differential
mix and dial in the percentage of
differential you want. That’s it.
Differential isn’t dependent upon the
mechanical linkage setup. Positive or
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negative values can be given to the mix so
that differential in the correct direction
can be set.
If you’re a sailplane pilot, you will love
all of the predefined mixes to help set up
crow, butterfly, brakes, etc., with the
ability to set differential flaps and reduced
differential. These are predefined, so all
you have to do is set the switches and
percentage. The majority of the work is
done for you.
The coup de grâce is the three free
mixes left for you to define however you
want them. Few radios allocate this many,
and the MX-16 iFS is the only one in its
price range I’ve seen that provides you
with three.
Few pilots will ever use the free mixes,
because so many are already defined. But
for those who experiment and design
helicopters or airplanes with controls
outside the normal realm of things, it’s a
godsend.
Model Memories: The transmitter has
memory to keep 12 aircraft programmed
all the time. They can be a mix of any
type, and the program mixes, etc. are kept
in each memory.
Every memory is a clean slate (in
Mode 1). So if you’re a Mode 2 person, as
I am, there’s a time-saving trick.
Select the mode you fly in the first
model memory, and then copy that model
to every model slot. If you fly helicopters,
you’ll also change the pitch-movement
direction. (Low pitch default is with the
stick reversed—full forward.)
Regardless of model type, an alarm for
safety will sound if the throttle is above
idle position when the transmitter is
turned on. Likewise, an alarm will sound
in the helicopter mode if the idle-up
switch is out of the normal mode, to help
prevent a hot start. There are three idle-up
choices.
The Receiver: The MX-16 iFS comes
with an eight-channel receiver, utilizing a
single stub antenna on the top. Each plug
is labeled with its number, and the
receiver arrives bound to the transmitter.
You can add more receivers and simply
follow the manual’s simple binding
instructions.
Once bound, the link is acquired
extremely fast. In advanced programming
modes, you can change many of the
receiver’s parameters, such as hopping
mode, etc. These must coincide with the
mode set in the transmitter.
One feature of the receiver that is
helpful in diagnosing issues of your setup
is the glowing orange LED. If that turns
from green to orange during operation, it
indicates that the voltage has dropped
below acceptable levels during the flight
or test run. Do not operate the airplane or
helicopter until you have diagnosed and
corrected this issue.
Most occurrences can be traced to not
using a large enough receiver battery or
an insufficient BEC unit. It requires only
a voltage dip below 4.4 longer than 25ms
to trigger the low-voltage warning.
When installing your receiver, ensure
that no wires can make contact or come
within close proximity of the receiver
antenna. This can cause interference,
regardless of the type of system in use.
People tend to think that the switch to
2.4 GHz eliminated all interference
problems, but you must still take care
when installing wires around the receiver
antenna. Secure them and you will have
no problems.
Because the MX-16 uses Xtreme
Power Systems’ (XPS’s) iFS radio
technology, any XPS receiver will work
with the Graupner radio. Besides the
standard eight-channel XtremeLink
receiver that is identical to the XR-16
included with the transmitter, the eightchannel
sailplane receiver for lighterweight
(low vibration) applications is now
available. The sailplane receiver is
equipped with an antenna extension, so
that the signal can be retrieved outside
carbon-fiber fuselages.
For park flyers, a great choice is the
six-channel XtremeLink receiver, which is
suitable for shorter range applications; it
doesn’t even have an external antenna. All
XPS receivers are licensed by the FCC.
An International Radio: I call it that,
because if you travel around the world on
business and like to carry a model with
you for leisure, you can set the MX-16
iFS for whatever country requirements
you encounter. It arrives programmed to
the US standard, so you’re set if you
don’t leave the country.
If you do travel abroad, you can reset
the output and hopping modes to be legal
elsewhere by going into the receiver’s
and transmitter’s advanced programming
modes, as described in the manual. This
is a big plus for those who travel to
international events.
The bottom line for me is how a system
performs in the air and how easy it is to
set up. In both cases, the MX-16 came
out a winner. Setup is simple, and the
predefined mixes and settings are all that
are needed in 90% of the cases. The link
between the radio and the model is solid,
even in a crowded environment.
At the field, using a foam trainer, and
in a controlled environment, I shut off the
transmitter while the airplane was in
level cruise, roughly 50 feet high, and
then turned the transmitter back on. As
soon as I did, the model went into the
fail-safe mode and regained control.
That action was quick and barely
noticeable. I don’t recommend that you
test your system this way, but under
controlled conditions it proved that the
solid link is rapidly restored.
If I had one wish, it would be that the
MX-16 iFS held more than 12 models in
memory. If that’s my only complaint—
and it is—the bottom line is that this radio
is a winner. MA
Greg Gimlick
[email protected]
Manufacturer/Distributor:
Graupner/Xtreme Power Systems
2440 Kiowa Blvd. N. #102
Lake Havasu City AZ 86403
[email protected]
www.xtremepowersystems.net
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