User Manual

PROG MIX – PROGRAMMABLE MIXERS
The XP9303 System provides 4 Standard programmable mixers (PROG.MIX3 - PROG.MIX6)
and 2 Multi-Point programmable mixers (PROG.MIX1 & PROG.MIX2). Programmable mixers
are used whenever the pilot wants a channel to react or move as a result of providing input to
another channel, or to simply cause a channel to move by moving a switch or lever. They are
typically used to compensate for deficiencies in aircraft design/setup such as eliminating pitch-
and roll-coupling in knife-edge flight, and to activate special aircraft functions like smoke
systems, speed brakes, bomb drops, idle-up, etc.
Multi-Point Mixing provides the ability to define a customized “curve” of travel that the Slave
channel will follow as it reacts to the Master channel. It is different from Normal Mixing in the
sense that Normal Mixing results in a linear movement of the Slave channel in relation to the
Master. With Multi-Point Mixing there are 7 points (including end points) along the travel of the
Master channel that can be adjusted to control the action of the Slave channel (more or less travel
in the same/opposite direction) providing the ability to deviate from a linear mixing action.
The channel that receives the original input from the pilot is called the Master channel, while the
channel that reacts to the Master is called the Slave channel. Mixing occurs when the pilot
provides an input to the Master channel by moving a stick, switch, or lever. The transmitter
automatically generates an input for the Slave channel based on the pilot's input to the Master
channel and the parameters defined in the programmable mixer.
Mixes are programmable, allowing any of the 9 channels to be Master, Slave or both. Other
mixing parameters are also programmable and include the direction of travel of the Slave
channel; the amount of travel for the Slave channel; the Offset (where the mix starts and changes
direction) and the switches/levers/sticks that are used to turn a mixer on and off. All of these
elements are adjustable in Programmable Mixers.
Some examples of how programmable mixers might be used include but are certainly not limited
to:
• Eliminate Roll-Coupling where the aircraft rolls when there is rudder input. The
mixer causes the ailerons to move just a little bit in the opposite direction of the
rudder in order to keep the aircraft from rolling while holding rudder for knife-edge
flight. This standard mixer would designate the Rudder as the Master and the
Ailerons as the Slave.
• Eliminate Pitch-Coupling where the aircraft pitches to the gear or canopy when
holding rudder for knife-edge flight. The mixer causes the elevator to move a little
when rudder is applied to keep the aircraft from pitching while holding rudder during
knife-edge flight. This Multi-Point mixer would designate the Rudder as the Master
and the Elevator as the slave. A Multi-Point mixer would be used because pitch-
coupling is typically non-linear in nature and requires a customized curve to
counteract pitching that is induced by different amounts of rudder deflection.
• Eliminate pulling out on down lines where the aircraft has a tendency to pull out
towards the canopy when flying vertical down lines at idle. The mixer generates a bit
of down elevator when the throttle stick is pulled back to idle making the aircraft
track straight down with no input from the pilot. This mixer would designate the
JR XP9303 Detailed Function Descriptions 73