Narco Avionics AR850 User manual

AR850 ALTITUDE REPORTER
(L/C)30,700ft
INSTALLATION/OPERATION MANUAL
30,700 FEET
MANUAL PART NO. 03753-0623
®NARCO AVIONICS INC.
270 COMMERCE DRIVE
FORT WASHINGTON, PENNSYLVANIA, 19034
U.S.A.
©COPYRIGHT, NARCO AVIONICS INC., 1990
PRINTED IN U.S.A. JULY, 2003

NOTICE
While every effort has been made by Narco Avionics Inc. to ensure
accuracy in the preparation of this Installation Manual, Narco
assumes no responsibility for errors or omissions.
NARCO AVIONICS INC. CAN BE REACHED BY CALLING:
PHONE: [phone]
FAX: [phone]
CUSTOMER SERVICE LINE: 215-643-2905
TABLE OF CONTENTS

SECTION TOPIC PAGE
1.1 Introduction ...................................... 1-1
1.1.1 Manual Organization ............................... 1-1
1.2 Product Description ............................... 1-1
1.3 Design Features ................................... 1-2
1.4 Product Specifications ............................ 1-2
1.5 Ordering Information for units/accessories ........ 1-4
1.6 Licensing Requirements ............................ 1-4
1.7 TSO Explanation ................................... 1-5
1.8 Environmental Qualification Form .................. 1-7
2.1 Introduction ...................................... 2-1
2.2 Preliminary Procedures ............................ 2-1
2.2.1 Preliminary Inspection ............................ 2-1
2.2.2 Preliminary Bench Check ........................... 2-1
2.3 Mechanical Installation ........................... 2-3
2.4 Electrical Installation ........................... 2-9
2.4.1 AR850 to Transponder Compatibility ................ 2-9
2.4.2 AR850 ENABLE Requirements ......................... 2-9
2.4.3 Primary Power Requirement ......................... 2-10
2.4.4 AR850 Altitude Code Line Characteristics .......... 2-10
2.4.5 Interconnect Cable Fabrication .................... 2-11
2.4.6 Correspondence Test ............................... 2-12
2.4.6.1 Test Equipment Requirements ....................... 2-12
2.4.6.2 Test Procedure .................................... 2-12
2.4.7 Interconnect Wiring Diagrams ...................... 2-14
2.4.7.1 AR850 to AT155/AT150/AT50/50A Installation ........ 2-14
2.4.7.2 AR850 to KING KT76/78 ............................. 2-15
2.4.7.3 AR850 to KING KT76A/78A/79 ........................ 2-16
2.5 Post Installation Tests ........................... 2-17
2.5.1 Preflight Tests ................................... 2-17
3.1 General ........................................... 3-1
3.2 Operation ......................................... 3-1
LIST OF ILLUSTRATIONS
FIGURE NO. TITLE PAGE
2-1 Bench Test Set-up ................................. 2-1
2-2 AR850 Mechanical Dimensions ....................... 2-4
2-3A AR850 Tray Template ............................... 2-5
2-3B AR850 Case Template ............................... 2-7
2-4 P101 Assembly ..................................... 2-11
2-5 P101 Pin Assignments .............................. 2-12
2-6 AR850 to AT155/AT150/AT50/50A Interconnections .... 2-14
2-7 AR850 to KT76/78 Interconnections ................. 2-15
2-8 AR850 to KT76A/78A/79 Interconnections ............ 2-16
7/03 1-i

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GENERAL INFORMATION
SECTION 1
7/03 1-1
1.1 INTRODUCTION
In support of the Narco Avionics AR850 Altitude Reporter, this
manual provides detailed installation and maintenance procedures.
This manual is intended for use by persons who are qualified to
service the equipment described in this manual pursuant to current
regulatory requirements.
1.1.1 MANUAL ORGANIZATION
Organized into three sections, this manual provides the following:
SECTION 1 GENERAL INFORMATION - Product description, ordering
information, specifications, environmental category
and licensing requirements.
SECTION 2 INSTALLATION - Detailed information for performing
the mechanical and electrical installation.
SECTION 3 OPERATION - Operation of the AR850 system is
covered only to the extent of making the electrical
tests necessary to confirm proper operation.
NOTE : Maintenance Manuals are not available to the field
because all maintenance not covered in this installation
manual must be performed at the factory for the
following reasons :
1. Sensor Scaling selected parts.
2. Special Programmed PROM for linearization of
the sensor output.
1.2 PRODUCT DESCRIPTION
The AR850 Altitude Reporter is a TSO'd pressure altitude
digitizer. Sensing atmospheric pressure, the AR850 converts
pressure/altitude information into digitized altitude data, ready
for transmission to air traffic control centers via the aircraft's
transponder during a Mode C interrogation.
The AR850 L/C (30,700 ft.) differs from the 25,000 and 30,700 ft.
versions in mechanical packaging and altitude limit only. The pin
out (because of the smaller connector) is different from the
original model. The electronics remain the same.
The AR850 L/C (30,700 ft.) is not pin compatible and requires
different mounting holes than Narco's older AR500 Atltitude
Reporter.

NARCO AVIONICS AR850
1-2 7/03
1.3 DESIGN FEATURES
- Reports altitude up to 30,700 feet (9,357 meters).
- Incorporates a Piezoresistive pressure sensor.
- No complex gears, shafts or optical discs are used
which increases the unit's reliability.
- Directly compatible with most current production
transponders.
- Meets FAA TSO C88(a).
- Lightweight: less than 1 pound.
- Compact: Remote mounts easily within the aircraft's
structure.
- Operates on either 14 or 28 Vdc.
1.4 PRODUCT SPECIFICATIONS
ALTITUDE REPORTING RANGE
-1,000 to 30,700 feet referenced to 29.92 inches of mercury.
CODE OUTPUT
The digitized output format is in accordance with the U.S.
National Standard for Common System Component Characteristics
for the IFF Mark X (SIF)/Air Traffic Control Radar Beacon
System, SIF/ATCRBS as amended December 27, 1963 and is the
same code specified in the International (ICAO) Standard Code
for SSR Pressure Altitude Transmission.
ACCURACY
The digitizer reproduces the pressure altitude in digital
form with a tolerance of ±50 feet referenced to 29.92 inches
of mercury as measured at any transition point of the digital
code over the range of -1,000 to 30,700 feet, as shipped from
the factory.
MECHANICAL
SIZE : See UNIT DIMENSIONS on page 2-4.
WEIGHT : AR850 Unit 0.7 lbs. ( 0.318 kg.)
AR850 Tray 0.090 lbs. (0.041 kg.)

GENERAL INFORMATION
SECTION 1
7/03 1-3
1.4 PRODUCT SPECIFICATIONS, Continued
ELECTRICAL
INPUT POWER : 11 to 32 Vdc at 1.4 amps maximum during
the first 3 minutes of operation. 0.35
amps average after 3 minutes of operation.
ENVIRONMENTAL
TSO C88 (a)
DO160B ENVIRONMENTAL CATAGORY B1B/A/NOM/XXXXXXBBBBBB
CODE LINE OUTPUT CHARACTERISTICS
Data bit outputs are compatible with DTL, TTL, MOS,
CMOS, ECL or any other logic interface requiring the
following characteristics:
BIT OFF OUTPUT STATE : Will accept from the transponder
a voltage pullup of +50 Vdc at a leakage current of 100
microamps.
BIT ON OUTPUT STATE : 0.75 Vdc at 50 ma. Sinking
current
1.1 Vdc at 100 ma. sinking
current
DIGITIZER ENABLE SIGNAL INPUT
The AR850 will accept continuous type digitizer enable signal
information.
DIGITIZER ENABLED:
1. J101-6 : When pin 6 is grounded the digitizer is
enabled.
DIGITIZER INHIBITED:
1. J101-6 : When pin 6 is open circuited or a DC
voltage greater than 0.5 volts is applied, the
digitizer is inhibited.

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1-4 7/03
1.5 ORDERING INFORMATION FOR UNITS AND ACCESSORIES
The following list identifies the AR850 system and the order
number to use to obtain the complete system. The accessory items
of the system may be ordered by using the part numbers listed
opposite the item.
┌──────┬─────────────┬─────────────────────────────┬────────────┐
││││Accessory/ │
│Item │Order No. │Description │Individual │
│No. │││Part No. │
├──────┼─────────────┼─────────────────────────────┴────────────┤
│1 │03753-0306 │AR850 L/C (30,700 ft.) 01447-0103 │
│││With : Installation Kit │
│││Environmental Qualification │
│││Form (03753-0621) │
│││(DOES NOT INCLUDE MOUNTING TRAY) │
├──────┼─────────────┼──────────────────────────────────────────┤
│││ACCESSORIES : │
│││Mounting Tray Kit 03753-0305 │
│││Installation Kit 03753-0503 │
├──────┼─────────────┼──────────────────────────────────────────┤
││Quantity │Installation Kit : │
│2 │1 │15 Pin Connector (P101) 41364-0004 │
│3 │1 │Connector Hood (P101) 41307-0011 │
│4 │15 │Connector Pins (P101) 41372-0010 │
││││
││││
│6 │2 │Screw, 4-40 x 5/8 84536-0708 │
│7 │1 │Cockpit Label, 30,700 ft. 04968-0001 │
└──────┴─────────────┴──────────────────────────────────────────┘
1.5.1 Miscellaneous Items Required but Not Supplied:
1. Sufficient length of #22 AWG stranded hook-up wire
2. A resettable circuit breaker or fuse rated at 2 amps for
device protection.
3. Sufficient length of 1/4 inch ID hosing to connect to
the AR850's plastic static adapter for venting to
atmosphere.
4. Mounting Hardware.
1.6 LICENSING REQUIREMENTS
There are no operator or aircraft license requirements for this
type of equipment.

GENERAL INFORMATION
SECTION 1
7/03 1-5
1.7 TSO EXPLANATION
The AR850 is designed to be remote mounted within a non-
pressurized but controlled temperature location within an aircraft
that is operated up to 30,700 MSL.
This equipment requires direct current power, but may be installed
in aircraft having additional on-board alternating current
sources.
There are 18 "Environmental Test Procedures" established in RTCA
Document DO-160B, dated July 1984. These are identified on the TSO
Nameplate. The following identifies the Environmental Categories
to which the AR850's are designed, the sections of DO-160B
covering the test procedures, and an explanation of each category.
Temperature and Altitude (Section 4.0 Rev. 1)
│Temperature Variation (Section 5)
││Humidity (Section 6)
│││Vibration (Section 8)
││││Explosion (Section 9)
│││││Waterproofness (Section 10)
││││││Fluid Susceptibility (Section 11)
│││││││Sand and Dust (Section 12)
││││││││
B1/B/A/NMO/X X X X X X Z B B B B B B
│││││││││
Fungus Resistance (Section 13)││││││││
Salt Spray (Section 14)│││││││
Magnetic Effect (Section 15)││││││
Power Input (Section 16)│││││
Voltage Spike (Section 17)││││
Audio Frequency Conducted Susceptibility (Section 18)│││
Induced Signal Susceptibility (Section 19)││
Radio Frequency Susceptibility (Section 20)│
Emission of Radio Frequency Energy (Section 21)
* AR850 also tested for shock operation (Sections 7, 7.2, 7.3).
Temperature and Altitude - Category B1
Temperature, Operating:
Low Operating Temperature -20°C (-4°F)
High operating Temperature +55°C (+131°F)
Short Time Operating Temperature, High +70°C (+158°F)
Temperature, Non-Operating:
Ground Survival Temperature, Low -55°C (-67°F)
Ground Survival Temperature, High +85°C (+185°F)
Altitude, Non-Pressurized: 7,620 M (25,000 ft.)

NARCO AVIONICS AR850
1-6 7/03
Temperature Variation - Category B
Low Operation (-20°C) to Temperature may vary between
High Operation (+55°C). high and low limits at a
rate of 5 degrees C minimum
per minute.
Humidity - Category A
These limits have been tested under the Standard Humidity
Environment of: +50°C (+122°F) at 95% relative humidity, reduced to
+38°C (+100°F) with a relative humidity maintained in excess of
85%.
This cycle was repeated twice for a total of 48 hours of exposure.
Within 15 minutes after exposure, the units were operated and met
all specifications.
[TSO requires that all specifications be met within 4 hours after
exposure.]
Vibration - Category NMO
Maximum vibration limits are:
0.100" double amplitude from 5 Hz. to 17 Hz.
1.5 G constant acceleration from 17 Hz. to 500 Hz.
0.5 G constant acceleration from 500 Hz. to 2000 Hz.
Not Applicable - Category X
The following six Environmental Conditions do not normally exist
in Civil Aircraft, when recognized installation practices are
adhered to and are, therefore, not tested.
Explosion - Category X
Waterproofness - Category X
Hydraulic Fluid - Category X
Sand and dust - Category X
Fungus Resistance - Category X
Salt Spray - Category X
Magnetic Effect - Category Z
With this equipment operating, it may be placed at a distance less
than 0.3 meter from a free magnet with a 1°or less deflection of
the magnet.

GENERAL INFORMATION
SECTION 1
7/03 1-7
Power Input - Category B
This equipment is designed for use in aircraft electrical systems
supplied by an engine driven alternator/rectifiers or DC generator
with a battery of significant capacity floating on the DC bus at
all times.
28V System 14V System
Normal Operating Conditions (Vdc) are:
Maximum 30.3 15.1
Nominal 27.5 13.8
Minimum 24.8 12.4
Voltage Spike - Category B
This equipment has been designed to withstand the transient
voltage characteristics specified by RTCA Document DO-160B.
Audio Frequency Conducted Susceptibility - Category B
This equipment has been designed and tested to assure compliance
with the requirements of RTCA Document DO-160B.
Induced Signal Susceptibility - Category B
This equipment has been designed to withstand the effects of audio
frequency electric and magnetic fields and induced voltage spikes
as specified by Category B.
Radio Frequency Susceptibility - Category B
This equipment has been tested and is not affected by interference
from other on-board electronic equipment which meet Category B,
Emission of Radio Frequency Energy Test of RTCA Document DO-160B.
Emission of Radio Frequency Energy - Category B
This equipment has been tested and does not emit radio frequency
energy in excess of that specified.
1.8 ENVIRONMENTAL QUALIFICATION FORM
An Environmental Qualification Form (Number 03753-0621) is
included with each AR850 shipped from the factory. This two page
form identifies the TSO categories to which the AR850 was designed
and tested as outlined in RTCA Document DO-160B dated July 1984.
The installing agency must ensure that the owner of the AR850 is
given this form which he should place in his avionics equipment
file.

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1-8 7/03
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INSTALLATION
SECTION 2
7/03 2-1
2.1 INTRODUCTION
This section provides all the electrical and mechanical installation
information. Electrical and Mechanical Installation sections are independent
and self-supporting. This permits their removal from the manual allowing the
electrical and mechanical installation efforts to proceed in parallel.
2.2 PRELIMINARY PROCEDURES
2.2.1 Preliminary Inspection
Carefully unpack the equipment, noting any damage to shipping
cartons or avionics. If damage is noted, retain the cartons to
corroborate damage claims.
Inventory the received items against the lists in Section 1.5 to
assure a complete order.
2.2.2 Preinstallation Bench Check
A preinstallation bench check may be performed without connection
to the transponder. The test equipment required is :
a. 14/28 Vdc, 2 amp power supply
b. Ohmmeter
c. Pitot Static System Test Set
Prepare an AR850 mating connector (similar to the connector in
section 2.4.5) as shown in Figure 2-1. Connect a clip lead to the
wire on pin 6.
FIGURE 2-1 BENCH TEST SET UP

NARCO AVIONICS AR850
2-2 7/03
2.2.2 Continued
1. Connect the AR850 to the Pitot Static System Test Set. Apply
14V or 28V power and allow the system to stabilize for 5
minutes.
2. Check pins 3, 4, 5, 9, 10, 11, 12, 13 with the ohmmeter. They
should all read a high resistance of 1 megohm or higher.
3. Clip pin 6 to ground.
4. Pump the AR850 to the following altitudes to check for
operation of all the code lines. An active code line will
read a low resistance of 200 ohms or lower.
USE EITHER LOWER OR HIGHER ALTITUDE TESTS
────────────────┬────┬────┬────┬─────┬────┬─────┬──────┬────
PIN NO. 2 │3 │4 │5 │9 │10 │11 │12 │13
││││││││
CODE LINE A1 │A2 │A4 │B1 │B2 │B4 │C1 │C4 │C2
────────────────┼────┼────┼────┼─────┼────┼─────┼──────┼────
ALTITUDE ││││││││
││││││││
2400 HI │HI │HI │LO │HI │HI │LO │HI │LO
2800 HI │HI │LO │LO │HI │HI │HI │LO │HI
5500 HI │HI │LO │HI │LO │LO │HI │HI │LO
7500 HI │LO │LO │HI │HI │LO │HI │HI │LO
15500 LO │LO │HI │HI │HI │LO │HI │HI │LO
││││││││
6500 HI │HI │LO │HI │HI │HI │HI │HI │LO
7300 HI │LO │LO │HI │HI │LO │LO │HI │HI
8600 HI │LO │LO │HI │LO │HI │HI │LO │LO
9500 HI │LO │LO │LO │LO │LO │HI │LO │LO
15500 LO │LO │HI │HI │HI │LO │HI │HI │LO
NOTE : LO denotes Low resistance
HI denotes High resistance
This completes the preinstallation bench check.

INSTALLATION
SECTION 2
7/03 2-3
2.3 MECHANICAL INSTALLATION
The AR850 must be located within the internal structure of the aircraft. The
location area to be non-pressurized and temperature controlled. It should be
located away from the heater or fresh air vents that lead to very rapid
changes of temperature. It may be mounted in any plane as well as inverted.
The mounting base should be adequately secured in accordance with all
applicable FARs. NO safety wire is necessary on the securing nut as a
friction locking material is incorporated on the screw.
Refer to Figure 2-2 for the mechanical dimensions of the unit and tray.
Figure 2-3A is a 1:1 Tray Template. Figure 2-3B is a 1:1 Case Template.
2.3.1 Static Connections
As shown here, a plastic static adapter is shipped installed on the AR850 to
facilitate preinstallation bench checks and/or installation with 1/4 inch ID
hosing to the aircraft's static system.
If another static connection is desired, the plastic adapter may be removed
and replaced with any other acceptable 1/8-27 NPTF fitting.
The 5/8 inch hex fitting is permanently secured to the AR850 and should NOT
be turned. Use a double wrench technique when installing or removing
connections or adapters. Secure the static line adequately to the fitting.

NARCO AVIONICS AR850
2-4 7/03
AR850 UNIT DIMENSIONS
TRAY DIMENSIONS
FIGURE 2-2 AR850 MECHANICAL DIMENSIONS (not to scale)

INSTALLATION
SECTION 2
7/03 2-5
FIGURE 2-3A AR850 TRAY (not to scale)

NARCO AVIONICS AR850
2-6 7/03
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INSTALLATION
SECTION 2
7/03 2-7
FIGURE 2.3B AR850 CASE MOUNTING (not to scale)

NARCO AVIONICS AR850
2-8 7/03
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