MU-9000X Specifications

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Technical Description:

Pilots who have been using the MU-1800-I / AP3 combination to setup their aircraft are most likely familiar with the specifications of the AP3 display unit. It is also shown on this page for convenience.

The MU-9000X is an absolute inclinometer utilizing MEMS (micro electro-mechanical systems) technology to sense tilt angles over a full 360 range in 2 axes. The MU-9000X incorporates a number of patent pending breakthroughs to create a new type of inclinometer that is rugged, compact, fast, lightweight and easy to use. The MU-9000X represents leading-edge advancement is MEMS technology and is the most advanced device available for aircraft setup.

Configurations and parameters which are stored at the factory in non-volatile memory include level, resolution, damping / averaging time, and direction. Damping is the amount of time over which angle readings are averaged and has been factory set to 500 milliseconds.

Temperature Ratings:

Operating Temperature
-40+25+85Degrees C

Supply Voltage Range:

Supply Voltage


Position Update Rate


0C - 50C, On Axis, 360°


Damping Time, Fixed

Measuring Unit Weight:

Total Weight Including Clamps & Plates


Measuring Plate


Measuring Unit Dimensions

AP3 Display

Technical Description:

The AP3 is a digital LCD readout designed to display the incremental count value of the MU-9000X. The AP3 features a sign indicator for displaying both positive and negative angles. Signals from the MU-9000X are filtered to ensure signal integrity over the entire input frequency range. The Match LED illuminates and relay closure occurs when an encoder count equals the zero angle. Under normal operation the relay closure feature is not needed. However the modeler may want to connect an external light or audio enunciation indicating zero angle has been reached. Please refer to the mechanical drawings and electrical specifications for proper implementation of this feature. Note that any angle reported by the MU-9000X can be reset to a zero reference angle.

The AP3 Digital Display is powered by the AP12, +12 Volt power supply (included- see below). Optionally, the display unit accepts power from an external battery through a standard 2.1mm DIN circular plug (see FAQ Page for further details). The AP3 Digital Display supplies the +5 VDC power for the MU-9000X.

Whenever the preprogrammed limits of +/- 0.5 degrees are exceeded, the AP3 digital display illuminates a corresponding High or Low LED. This feature is quite useful since it lets the user know when the angle is approaching zero.

The AP3 is constructed of a lightweight high impact polymer case with a clear viewing window. The AP3 display offers 0.5" high digits with blue backlighting. Leading Zero Blanking provides superior readability! (New, October 2006). The AP3 front panel thickness may range up to a maximum of 0.125" thick.

Mechanical Drawings:

Back and Side Views

AP3 Mechanical Dimensions

Panel Cutout Drawing

AP3 Panel Cutout Dimensions

Installation Instructions:

Note: It is very important that care be exercised when opening the case. Do not touch any of the electrical components as static discharge can damage them. Do not force the AP3 into an undersize cutout or over-tighten the screws when reinstalling the case. Damage resulting from improper installation is not covered under the terms of the AeroPerfect™ Warranty.

Electrical Specifications:

Parameter Min Typ Max Units
Supply Voltage 7.5 - 30 Volts
Supply Current* - - 40 mA
Encoder Input Cycle Frequency - - 1.2 MHz
Relay Contact Rating*** - - 3.0 Amps
Relay Switching Rating****

Relay Dielectric Stength 500 - - VAC
Relay Contact Resistance - - 100 uOhms
Enocder Output Voltage** 4.8 5.0 5.2 VDC
Encoder Supply Current - - 250 mA
Encoder Low Input - 0.4 0.8 VDC
Encoder High Input 2.0 5.0 5.75 VDC

* Without MU-9000X attached.
** 100mA load.
*** At rated AC or DV voltage.
**** An external clamp diode should be used when switching inductive loads.

AP-12 Power Supply


The AP-12 is an 18W regulated switching power supply that provides 12VDC @ 1.5A output. The power supply covers voltage inputs ranging from 90 to 264VAC and 47 to 63Hz which accommodates most international power requirements. Typical efficiency is 70% and output is short circuit protected.

The power supply DC output uses a 2.1mm circular plug (center positive) which is attached to a 48 inch long cable. The power supply plugs directly into a standard 120VAC receptacle or the appropriate AC plug adapter (see below).

Mechanical Drawing:

AP-12 Power Supply Drawing


Input Voltage90 to 264VAC
Input Frequency47 to 63Hz
AC Plug Type2-Prong, USA Type, non-polarized
Output Voltage12VDC
DC Output Plug5.5 x 2.1 x 9.5 mm female barrel, center positive
Load Regulation5%
Ripple & Noise40mV maximum
Operating Temperature0 to 40C
Storage Temperature-30 to 80C
ProtectionsOver voltage, Over current and Short circuit
CertificationUL 1950, CB (per EN 60950)
EMIMeets FCC class "B"
AC Input IndicatorGreen LED
Size (inches)3.15 x 2.16 x 1.26 (WLH)


AP-12 Power Supply Photograph

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