Mid-Continent Instruments MD41 Series Technical Document

INSTALLATION MANUAL AND
OPERATING INSTRUCTIONS
MD41-( ) Series GPS Annunciation Unit
For Garmin GNS 430/430W/530/530W VHF
Communication and Navigation Management System
MD41-1484W 14VDC Horizontal Mount
MD41-1488W 28VDC Horizontal Mount
MD41-1494W 14VDC Vertical Mount
MD41-1498W 28VDC Vertical Mount
MID-CONTINENT INST. CO., INC MANUAL NUMBER 9016478

REV. C 2April 24, 2007
Revision History
ECO Rev. Date Detail
N/R 01/19/07 Initial release.
A 02/15/07 J1 connector was 9016475, now 9016479.
B 03/12/07 Corrected section 4.1 to show proper pins,
corrected mating connector rear view.
4828 C 4/24/07 Correct connector schematic pinout in section
1.2.5. Add –1494W and –1498W versions.

REV. C 3April 24, 2007
TABLE OF CONTENTS
SECTION 1 GENERAL DESCRIPTION
1.1 INTRODUCTION
1.2 SPECIFICATIONS, TECHNICAL
1.2.1 PHYSICAL CHARACTERISTICS
1.2.2 ENVIRONMENTAL CHARACTERISTICS
1.2.3 SPECIFICATIONS, ELECTRICAL
1.2.4 FRONT PANEL CONTROLS AND ANNUNCIATIONS
1.2.4.1 CONTROLS
1.2.4.2 ANNUNCIATIONS
1.2.5 INTERFACE
1.2.6 EQUIPMENT LIMITATIONS
1.2.7 MAJOR COMPONENTS
SECTION 2 INSTALLATION CONSIDERATIONS
2.1 COOLING
2.2 EQUIPMENT LOCATION
2.3 ROUTING OF CABLES
SECTION 3 INSTALLATION PROCEDURE
3.1 GENERAL INFORMATION
3.2 UNPACKING AND INSPECTING
3.3 MOUNTING THE MD41-( )
3.4 INSTALLATION LIMITATIONS
SECTION 4 POST INSTALLATION CHECKOUT
4.1 PRE-INSTALLATION TEST
4.2 OPERATING INSTRUCTIONS
FIGURES LIST OF ILLUSTRATIONS
3.1 SCHEMATIC PINOUT, 15 PIN HIGH DENSITY D-SUB
3.2 OUTLINE DRAWING
3.3 INSTRUMENT PANEL MOUNTING
3.4 WIRING DIAGRAM, MD41-1484W/1488W/1494W/1498W
APPENDIX RTCA DO-160C ENVIRONMENTAL QUALIFICATION FORM

REV. C 4April 24, 2007
SECTION 1 GENERAL DESCRIPTION
1.1 INTRODUCTION
The MD41-( ) is a compact, self-contained GPS Annunciation unit. This unit
displays status annunciation received from the Garmin GNS 430/430W/530/530W
series GPS navigation management systems.
Features include dual 20,000 hour lamps used for all annunciations along with
automatic photocell dimming. An external annunciation dimming adjustment is
provided for balancing low-level light conditions.
1.2 TECHNICAL SPECIFICATIONS
1.2.1 PHYSICAL CHARACTERISTICS
Mounting: Front mount, panel
Width: 2.45 inches
Height: 0.75 inches
Depth: 2.60 inches (max)
Weight: 0.2 pounds
1.2.2 ENVIRONMENTAL CHARACTERISTICS
TSO Compliance: TSO C129
Applicable Documents: RTCA DO-160C, DO-208
Operating Temperature Range: -55°C to +70°C
Humidity: 95% Non-Condensing
Altitude Range: 0 to 55,000 ft.
Vibration: RTCA DO-160C, Cat. M and N
Operational Shock: Rigid Mounting, 6G Operational
15 G Crash Safety

REV. C 5April 24, 2007
1.2.3 ELECTRICAL SPECIFICATIONS
Design All Solid State
MD41-1484W (14VDC) 0.30 Amps
MD41-1488W (28VDC) 0.25 Amps
MD41-1494W (14VDC) 0.30 Amps
MD41-1498W (28VDC) 0.25 Amps
1.2.4 FRONT PANEL CONTROLS AND ANNUNCIATIONS
1.2.4.1 ANNUNCIATIONS
VLOC NAV or ILS information presented on the HSI or CDI
GPS GPS information presented on the HSI or CDI
MSG ON indicates message(s) active.
WPT ON indicates reaching the arrival waypoint.
TERM ON indicates aircraft is within 30 miles of departure or
arrival airport
APR ON indicates the approach is active.
INTG ON indicates GPS receiver detected a position error
or is unable to calculate the integrity of the position
1.2.5 INTERFACE
INTG annunciation Requires a logic low to annunciate
J1 Pin 1
WPT annunciation Requires a logic low to annunciate
J1 Pin 2 when in VOR/ILS mode
MSG annunciation Requires a logic low to annunciate
J1 Pin 3
TERM annunciation Requires a logic low to annunciate
J1 Pin 4
APR annunciation Requires a logic low to annunciate
J1 Pin 6
VLOC annunciation Receives ground from GNS 430/530
J1 Pin 7
GPS annunciation Receives ground from GNS 430/530
J1 Pin 8 when in GPS mode.
Lamp Test Receives ground from remote test switch
J1 Pin 10 to light all annunciations (optional connection)
J1 Pin 15 Ground

REV. C 6April 24, 2007
1.2.6 EQUIPMENT LIMITATIONS
The MD41-( ) series control units contain specific dash numbers to be used with
various GPS receivers or Navigation Management Systems. The installer must match
the correct controller part number with the system being installed.
The conditions and tests required for TSO approval of this article are minimum
performance standards. It is the responsibility of those desiring to install this article
either on or within a specific type or class of aircraft to determine that the aircraft
installation conditions are within the TSO standards. The article may be installed
only if further evaluation by the applicant documents an acceptable installation and
is approved by the Administrator.
The MD41-1484W/1488W/1494W/1498W are TSO certified and approved for use
with the Garmin GNS 430/430W/530/530W system. This includes the (A), (W) and
TAWS system versions of the Garmin equipment. Any attempts to install the listed
units in an installation other than the GNS 430/530 system is prohibited.
This will void the TSO.
NOTE: If the MD41-( ) is disconnected or removed from the aircraft, it will not
affect the operation of the GNS 430/430W/530/530W.
1.2.7 MAJOR COMPONENTS
This system is comprised of one major component, the MD41-
1484W/1488W/1494W/1498W GPS Annunciation Control Units.

REV. C 7April 24, 2007
SECTION 2: INSTALLATION CONSIDERATIONS
2.1 COOLING
No direct cooling is required. As with any electronic equipment, overall reliability may
be increased if the MD41-( ) is not located near any high heat source or crowded next
to other equipment. Means of providing a gentle airflow will be a plus.
2.2 EQUIPMENT LOCATION
The MD41-( ) must be mounted as close to the pilot’s field of view as possible. The
preferable location is near the HSI/CDI that will be displaying the GPS/VLOC
information. The unit depth, with connector attached, must also be taken into
consideration. Note: Unlike previous versions of the MD41 Annunciation Control Units
(ACU), the transfer relays are not required since the GNS 430/530 handles all
switching between GPS, VOR and ILS. This has allowed for a smaller size ACU that
now provides more options for panel mounting.
2.3 ROUTING OF CABLES
Care must be taken not to bundle the MD41-( ) logic and low level signal lines with
any high energy sources. Examples of these sources include 400 HZ AC, Comm,
DME, HF and transponder transmitter coax. Always use shielded wire when shown
on the installation print.
Avoid sharp bends in cabling and routing near aircraft control cables.

REV. C 8April 24, 2007
SECTION 3: INSTALLATION PROCEDURES
3.1 GENERAL INFORMATION
This section contains interconnect diagrams, mounting dimensions and other
information pertaining to the installation of the MD41-( ). After installation of cabling
and before installation of the equipment, ensure that power is applied only to the pins
specified in the interconnect diagram.
3.2 UNPACKING AND INSPECTING EQUIPMENT
When unpacking equipment, make a visual inspection for evidence of damage
incurred during shipment. The following parts should be included:
1. MD41-1484W (14VDC) or MD41-1488W (28VDC) Horiz. Mount
MD41-1494W (14VDC) or MD41-1498W (28VDC) Vertical Mount
2. Installation kit P/N 9016480 consisting of the following items:
A. J1 Connector Kit (15 pin) MCI P/N 9016479
B. 2 ea mounting brackets MCI P/N 8018483
C. 4 ea 4-40x ½ pan Phillips screws MCI P/N 90-416-00011
D. 2 ea 4-40x 9/16 flat Phillips screws MCI P/N 90-418-10011
E. 1 ea panel cutout template MCI P/N 8018954
3. Installation Manual MCI P/N 9016478
3.3 MOUNTING THE MD41-( )
Plan a location in the aircraft for the MD41-( ) to be mounted as close to the pilot’s
field of view as possible. The preferable location is near the HSI/CDI that will be
displaying the GPS information. Avoid mounting close to heater vents or other high
heat sources. Allow a clearance of at least 3 inches from back of unit for plug
removal.
Use the dimensions shown in figure 3-3 to prepare opening and screw holes for the
ACU. A file template has been provided to use for these measurements and hole
cutout Carefully measure the locations for the screw holes and mark the drill locations
with a center punch. Drill all six holes. A steel template (P/N 8018954) is supplied to
aid in locating holes and cutting out the panel. The template may be mounted to the
instrument panel to allow a file to be used to complete the cutout area. The front plate
of the ACU has a recessed area on the back so a flat head screw is not absolutely
necessary. Attach the mounting brackets to the rear side of the instrument panel with
four 4-40x1/2 pan-head screws. Insert the ACU through the front of instrument panel
and fasten with two 4-40 x 9/16 flat-head screws.

REV. C 9April 24, 2007
3.4 INSTALLATION LIMITATIONS
Wire the aircraft harness according to figure 3-3. Use at least 24 AWG wire for all
connections. Avoid sharp bends and routing cable near high-energy sources. Care
must be taken to tie the harness away from aircraft controls and cables. Normal
installation techniques should be applied. Also see equipment limitations, section
1.2.6.
REAR VIEW OF MATING CONNECTOR
Pin # Pin #
1 INTG Annun. 9 Reserved
2 WPT Annun. 10 Lamp Test
3 MSG Annun. 11 Reserved
4 TERM Annun. 12 Reserved
5 28 VDC Power 13 Reserved
6 APR Annun. 14 Reserved
7 VLOC Annun. 15 Ground
8 GPS Annun.
Connector Pinout
FIGURE 3-1 SCHEMATIC PINOUT, 15 PIN HIGH DENSITY D-SUB

REV. C 10 April 24, 2007
FIGURE 3-2 OUTLINE DRAWING
2.450
0.150
2.150
0.375
0.750
2.392 MAX
0.150
15-pin
High Density
D-Sub
2.150
2.450
0.150
0.375 0.750
MD41-1484W, MD41-1488W MD41-1494W, MD41-1498W