Sanden SN3500 User manual

82005-IM-K
SN3500
Primary Navigation Display
Installation Manual
Sandel Avionics, Inc.
2401 Dogwood Way
Vista, CA 92081
Phone [phone]
FAX [phone]
Website: www.sandel.com
Email: [email protected]

82005-IM-K Sandel SN3500 Installation Manual Page ii
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82005-IM-K Sandel SN3500 Installation Manual Page iii
Table of Contents
1General Information.......................................................................................................1-1
1.1 Introduction ..................................................................................................................................................1-1
1.1.1 EXPORT CONTROL NOTICE .............................................................................................................1-1
1.2 Equipment Description...............................................................................................................................1-1
1.2.1 Features .................................................................................................................................................1-1
1.3 Installation Planning ...................................................................................................................................1-2
1.3.1 Installation Planning Cycle ....................................................................................................................1-2
1.3.2 Post Installation Summary.....................................................................................................................1-3
1.4 Interface Planning........................................................................................................................................1-3
1.4.1 Compass System...................................................................................................................................1-3
1.4.2 Autopilot Switching.................................................................................................................................1-4
1.4.3 Autopilot Course and Heading Datum..................................................................................................1-5
1.4.4 GPS Annunciators .................................................................................................................................1-5
1.4.5 VLOC Navigation – Internal NAV Converter ........................................................................................1-5
1.4.6 VLOC Navigation – External NAV Converter.......................................................................................1-5
1.4.7 Marker Beacon.......................................................................................................................................1-6
1.4.8 Bearing Pointers (VOR, ADF, and TACAN).........................................................................................1-6
1.4.9 ARINC Channels ...................................................................................................................................1-7
1.4.10 DME Interface ........................................................................................................................................1-7
1.4.11 Special Considerations for GARMIN GNS430/530 Series..................................................................1-7
1.4.12 Special Considerations for UPS GXXX ................................................................................................1-8
1.4.13 Brightness Control .................................................................................................................................1-8
1.4.14 Traffic......................................................................................................................................................1-8
1.4.15 Data Link Weather .................................................................................................................................1-8
1.4.16 TACAN ...................................................................................................................................................1-9
1.4.17 Night Vision Support Option............................................................................................................... 1-10
1.4.18 Reversionary Attitude Option ............................................................................................................. 1-10
1.5 Disclaimer .................................................................................................................................................. 1-10
2Technical Information ...................................................................................................2-1
2.1 General ..........................................................................................................................................................2-1
2.2 Part Numbers ...............................................................................................................................................2-1
2.2.1 Installation Kit and Accessories ............................................................................................................2-2
2.2.2 Bill of Materials – SN3500 Install Kit .....................................................................................................2-2
2.3 Approval Summary .....................................................................................................................................2-2
2.3.1 License Requirements...........................................................................................................................2-2
2.3.2 Approval Data ........................................................................................................................................2-2
2.3.3 Technical Standard Order Stipulation...................................................................................................2-3
2.3.4 Installation and Operational Approval Procedures...............................................................................2-3
2.4 Physical, and Electrical Properties...........................................................................................................2-5
2.4.1 Physical Dimensions..............................................................................................................................2-5
2.4.2 Summary Operational Characteristics..................................................................................................2-5
2.5 Connector Summary...................................................................................................................................2-5

82005-IM-K Sandel SN3500 Installation Manual Page iv
2.5.1 Connector P1 .........................................................................................................................................2-6
2.5.2 Connector P2 .........................................................................................................................................2-9
2.5.3 Connector P3 ...................................................................................................................................... 2-12
2.5.4 Signal Characteristics Table............................................................................................................... 2-13
2.6 ARINC 429.................................................................................................................................................. 2-15
2.6.1 ARINC 419/429 Serial Data Receivers Interfaces ............................................................................ 2-15
2.6.2 ARINC 419/429 Serial Transmitter Interfaces................................................................................... 2-17
3Installation ......................................................................................................................3-1
3.1 General ..........................................................................................................................................................3-1
3.1.1 Unpacking and Inspecting Equipment..................................................................................................3-1
3.2 Installation Considerations........................................................................................................................3-1
3.2.1 General Considerations.........................................................................................................................3-1
3.2.2 Cooling Considerations .........................................................................................................................3-1
3.2.3 Mechanical Installation Considerations ................................................................................................3-1
3.2.4 Electrical Installation Considerations ....................................................................................................3-2
3.3 Signal Details................................................................................................................................................3-4
3.3.1 Connector P-1 Pinout Description.........................................................................................................3-4
3.3.2 Connector P-2 Pinout Descriptions.......................................................................................................3-7
3.3.3 Connector P-3 Pinout Descriptions.................................................................................................... 3-10
4Setup Procedures ..........................................................................................................4-1
4.1 General ..........................................................................................................................................................4-1
4.2 Accessing the Maintenance Menus..........................................................................................................4-1
4.3 Equipment/Configuration Selections.......................................................................................................4-1
5Operating Details ...........................................................................................................5-1
6Instructions For Continued Airworthiness.................................................................6-1
6.1 General ..........................................................................................................................................................6-1
7Appendix A: Post-Installation Procedures ................................................................7-1
7.1.1 Page 1: INDEX......................................................................................................................................7-2
7.1.2 Page 2: SYSTEM..................................................................................................................................7-3
7.1.3 Page 3: COMPASS SYSTEM .............................................................................................................7-4
7.1.4 Page 4: ADF/TACAN/ MKR .................................................................................................................7-7
7.1.5 Page 5: NAV/ILS/DME 1 ......................................................................................................................7-9
7.1.6 Page 6: NAV/ILS/DME 2 ................................................................................................................... 7-12
7.1.7 Page 7: GPS1 .................................................................................................................................... 7-14
7.1.8 Page 8: GPS2 .................................................................................................................................... 7-16
7.1.9 Page 9: FCS EMULATION ............................................................................................................... 7-18
7.1.10 Page 10: OBS / RELAY / CDI ........................................................................................................... 7-20
7.1.11 Page 11: WX-500 .............................................................................................................................. 7-22
7.1.12 Page 12: Traffic.................................................................................................................................. 7-23
7.1.13 Page 13: STATUS ............................................................................................................................. 7-24
7.1.14 Page 14: BRT/DATA BLK ................................................................................................................. 7-25
7.1.15 Page 15: Power ................................................................................................................................. 7-27

82005-IM-K Sandel SN3500 Installation Manual Page v
7.1.16 Page 16: Software CRC .................................................................................................................... 7-28
8Appendix B: Environmental Qualification Form.......................................................8-1
9Appendix C: Sample FAA Form 337...........................................................................9-1
10 Appendix D: Sample Airplane Flight Manual Supplement ....................................10-1
11 Appendix E: Checkout Procedures..........................................................................11-1
11.1 Functional Ground Test Procedures/Report........................................................................................11-1
11.1.1 Introduction.......................................................................................................................................... 11-3
11.1.2 Test Procedures and Results............................................................................................................. 11-3
11.1.3 Physical Installation ............................................................................................................................ 11-3
11.1.4 Wiring Verification and Initial Power-Up ............................................................................................ 11-3
11.1.5 System Configuration ......................................................................................................................... 11-4
11.1.6 System Functions ............................................................................................................................... 11-4
11.1.7 Compass System Interface ................................................................................................................ 11-4
11.1.8 NAV Source Selection........................................................................................................................ 11-5
11.1.9 LOC/GS Deviation .............................................................................................................................. 11-6
11.1.10 BRG Source Selection.................................................................................................................... 11-6
11.1.11 DME Selection ................................................................................................................................ 11-6
11.1.12 GPS Interface and Control ............................................................................................................. 11-7
11.1.13 Marker Beacon Interface ................................................................................................................ 11-8
11.1.14 Flight Control System Interface...................................................................................................... 11-9
11.1.15 Stormscope ® Interface.................................................................................................................. 11-9
11.1.16 Traffic............................................................................................................................................... 11-9
11.1.17 NVIS Control ................................................................................................................................. 11-10
11.1.18 Reversionary Display Control....................................................................................................... 11-10
11.1.19 Additional Testing.......................................................................................................................... 11-10
11.2 EMI/RFI Test Procedures....................................................................................................................... 11-10
11.2.1 Nav/Com Testing .............................................................................................................................. 11-10
11.2.2 General Testing................................................................................................................................. 11-11
11.2.3 Additional Testing ............................................................................................................................. 11-12
11.3 Operational Flight Test Procedures/Report ....................................................................................... 11-13
11.4 Introduction ............................................................................................................................................. 11-15
11.5 Test Procedures...................................................................................................................................... 11-15
11.5.1 Pre-Departure Operations................................................................................................................ 11-15
11.5.2 Enroute Operations........................................................................................................................... 11-16
11.5.3 GPS Approach Operations............................................................................................................... 11-17
11.5.4 TACAN Approach Operations.......................................................................................................... 11-17
11.5.5 ILS Approach Operations................................................................................................................. 11-17
11.5.6 Additional Testing ............................................................................................................................. 11-18
12 Appendix F: List of Effective Drawings and Attachments ....................................12-1

82005-IM-K Sandel SN3500 Installation Manual Page vi
Revision History
Revision Date Comments
K 11/30/2010
Updated for software version 4.03 AR1154
Section 1.1.1: Added TACAN ITAR Export Notice. Removed NVIS notice.
Section 1.3.1: Added list of recommended crimp tools.
Section 2.2.2: Positronics P/Ns added for connectors
Section 2.6.1: Updated 429 Label Description table.
Section 2.6.2: Table formatting updated.
Section 7.1.14: Changes to maintenance page 14: added procedure for
calibrating the minimum brightness when an external brightness control is
used.
J 05/27/10
Updated for software version 4.02 AR1110.
Corrected TOC
Section 3.3.2: Updated P2-3/35 pin description and added note for composite
LOC DEV calibration procedure.
Section 7.1.2: New TACAN Relay out pin configuration.
Section 7.1.3: New Reversionary Attitude Enable pin configuration.
Section 7.1.5: Added composite LOC DEV calibration procedure. Added
reference to cal procedure and added GAIN selection to table. Updated figure.
Section 7.1.6: Added reference to cal procedure and added GAIN selection to
table. Updated figure.
Section 7.1.14: New Dimmer Control configuration.
Section 11.1.9: Added LOC/GS deviation test. Following sections
renumbered.
Section 12: DWG 82005-10 sheet 41
I N/A Intentionally skipped.
H 8/24/09
Updated for software version 4.01 AR1087.
Section 3.3.1 change inverter range from 360 - 440Hz. to 240 - 560 Hz.
Section 3.3.2 change inverter range from 360 - 440Hz. to 240 - 560 Hz.
Section 7.1.1 corrected reference from ST3400 to SN3500.
G 3/2/09
Updated for software version 4.00 AR1055.
Page vi: Updated revision history.
Section 1.2.1: Added Optional Reversionary Display.
Section 1.4.17: Added NVIS paragraph
Section 1.4.18: New Reversionary Display paragraph.
Section 2.3.2: added TSO-C3d, and –C4c.
Section 2.5.3: Added REV CNTRL Label to connector pin 6.
Section 2.6.1: Added ARINC labels for Roll, Pitch, and Lateral Acceleration.
Section 3.3.3: Added Reversionary Control signal to connector P3 pin 6.
Section 7.1.3: Updated compass maintenance page for Reversionary Attitude.
Section 7.1.4: Added TACAN 1 & 2 Multi-Channel selection.
Section 7.1.5: Added DME1 Multi-Channel selection.
Section 7.1.6: Added DME2 Multi-Channel selection.
Section 11.1.17: Added ground test procedure.
Section 12: Added 82005-41 to drawing list.
F 8/26/08
Updated for software version 3.05, AR1032.
Page 2-12: Assigned P3-13 to NVIS Control
Page 3-12: Added NVIS P3-13 description
Page 7-20: Modified Maint. Page 14. (NVIS control monitor)
Page 11-10: Added NVIS ground test step
Page 12-2: Added 82005-10 pp 40, updated revisions.

82005-IM-K Sandel SN3500 Installation Manual Page vii
Revision Date Comments
E 6/16/08
Updated for software version 3.04 and TACAN support
Page 1-1: Added export control notice.
Page 1-2: TACAN added.
Page 1-6: TACAN added to bearing pointer inputs.
Page 1-8: NVIS Display Brightness / [M] button LED operation note added.
Page 1-8: TACAN added
Page 2-1: Low voltage operation support note added
Page 2-1: Update part number definition
Page 2-2: USB cable added to Bill of Materials
Page 2-5: Low voltage operation note added
Page 2-6: TACAN added
Page 2-9: TACAN added
Page 2-15: TACAN label added
Page 3-4: TACAN added to pinout description
Page 3-7: TACAN added to pinout description
Page 7-1: Index page updated for TACAN capability
Page 7-20: Page updated for NVIS brightness/ M button LED status
Page 11-5: TACAN added to NAV source selection
Page 11-6: TACAN added to bearing source selection
Page 11-15: TACAN added to enroute operations checks
Page 11-16: TACAN approach operations added.
D1 01/31/08
A/R 958
Updated Effective drawing list.
Modified 82005-10 sheet 28.
Added 82005-10 sheet 38
D 11/15/07
A/R 924
Page 1-1: Updated applicable TSOs and ETSO.
Page 2-1: Lamp kit added.
Page 2-2: Updated applicable TSOs and ETSO
Pages 3-9 & 3-10: Clarify pin description P2-28, P2-13.
Clarify composite input connection with analog NAVs.
Page 3-9: Clarify P2-10 HDG/CRS Excitation connection when not connected.
Page 5-1: Added reference to 82005-PG (SN3500 Pilot’s Guide) for light
source identification and data color coding details.
Page 7-1: Updated INDEX maintenance page image.
Page 7-10: Updated GPS-1 maintenance page image.
Pages 7-10 & 7-12: Added selections for ARINC 429 on GPS 1 and GPS 2
maintenance pages.
Page 7-11: Updated GPS-2 maintenance page image.
Pages 7-11 & 7-12: Added selections for GPS Approach Mode Active Status
on GPS1 and GPS2 maintenance pages.
Page 7-15: Added definition for lateral and vertical deviation output calibration
in maintenance pages.
Page 7-18: KTA-810 configuration note added.
Page 7-19: Updated BRT/DATA BLK maintenance page image.
Page 8-2: RTCA/DO-160E Environmental Qualification Form added.
C1 12/16/05
A/R 824 Updated following pages: Page iv, revision; Page 2-4, weight in kg;
Pages 2-6 and 3-5, deviation left/right; Pages 3-9 and 7-13, FCS selection;
Page 3-12, P3-10 NAV menu typo; Pages 12-1 and 12-2, drawing rev
updates. Pages 1, 33 & 36 of installation drawings updated.
C 11/17/2005
A/R 806 & A/R 820 Updated for software version 2.01, version 3.00, and minor
corrections. Sample AFMS updated including FIS-B weather.
B N/A Skipped
A3 06/06/2005 A/R 782 Minor doc changes for production release
A2 05/06/2005 A/R 782 Minor doc changes and pin-out corrections

82005-IM-K Sandel SN3500 Installation Manual Page viii
Revision Date Comments
A1 04/21/2005 A/R 780 minor doc and dwg changes
A 03/31/2005 Initial release

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-1
1General Information
1.1 Introduction
The information contained within this Installation Manual describes the features,
functions, technical characteristics, components, approval procedures, installation
considerations, setup procedures, checkout procedures, and instructions for
continued airworthiness for the Sandel Avionics SN3500 Primary Navigation Display.
The SN3500 is the industry’s most capable electronic HSI. It can be used to directly
replace a mechanical DG or HSI as a primary display, or the SN3500 can be used as
a replacement or upgrade for an existing Sandel SN3308 navigation display. It is
signal (but not plug) compatible with the SN3308, and is an upgrade in performance
with both an improved display and added features.
1.1.1 EXPORT CONTROL NOTICE
The TACAN display option software key (p/n 90143-TCN) is subject to the licensing
jurisdiction of the Department of State in accordance with the International Traffic in
Arms Regulations (ITAR) (22 CFR 120 – 130). It may not be exported (sent,
transferred, disclosed or otherwise released to a foreign person) without a license
issued by DDTC.
1.2 Equipment Description
1.2.1 Features
The Sandel SN3500 Primary Navigation Display is an advanced microprocessor
controlled airborne multipurpose electronic display which is FAA approved under
technical standard order TSO C6d, C34e, C35d, C36e, C40c, C41d, C113, C118,
and C119b. The SN3500 is also EASA approved under ETSO C113. The SN3500
employs a patented active matrix liquid crystal (AMLCD) projection display. It is
designed to combine the functions of:
Basic Horizontal Situation Indicator (HSI)
Long-Range Navigation (GPS or FMS) Map Display
WX-500 Stormscope® Display
DME Readout
Marker Beacon Indicator
NAV Converter
Autopilot Switching
GPS Annunciators and External Mode Switches
Traffic Display
FIS-B Data Link weather display (software version 3.00 and above)
Optional Class B Night Vision (NVIS) Compatible (Software 3.04 and above)
Optional Reversionary Attitude Display (Software 4.00 and above)

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-2
Outputs of heading and course datum and bootstrap heading output are provided, as
well as L/R and U/D deviation output and flags. The versatile digital and analog
interface properties of the unit provide for compatibility with most VHF navigation
receivers, ADF’s, TACAN’s, DME’s, GPS’s, remote gyros and flux gates.
The SN3500 is designed to display the flight plan data from a connected GPS
receiver. The moving map database for the SN3500 as well as the internal operating
system software are field loadable through the use of a portable computer equipped
with a USB port and a USB capable version of Microsoft Windows.
Although simple, retrofit replacement of most existing three-inch PNI’s or HSI’s is
possible without additional features, we strongly encourage complete installation of
the unit with all compatible peripheral equipment interconnected to maximize its
functional capability.
1.3 Installation Planning
Sandel Avionics has taken many equipment interface possibilities into consideration
during the design of the SN3500 to ensure maximum interoperability with other
avionics. Contact the factory with any questions about interfacing to specific avionics
equipment not covered in the installation drawings.
To simplify installation and installation planning, signals are wired to the SN3500 pins
per the installation diagrams and software setups are used in a post-installation
procedure to assign protocols/gradients to each pin based on the equipment
connected. There are separate maintenance menu pages for each equipment
function and in most cases the selections are made by equipment make/model.
1.3.1 Installation Planning Cycle
1) Compile an equipment list for the aircraft.
2) Study the feature list below, and determine the desired functional
characteristics for the installation.
3) Study the installation drawings to determine a basic interconnect scheme
and check for conflicts.
4) Develop the specific wiring diagrams unique to the aircraft.
5) Assemble required tools. Recommended crimp tools are given in the
following table.

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82005-IM-K Sandel SN3500 Installation Manual Page 1-3
Recommended Crimp Tools
High Density
22-28 AWG
Standard Density
20-24 AWG
Manufacturer Hand Crimping
Tool Positioner
Insertion/
Extraction Tool Positioner
Insertion/
Extraction Tool
Military P/N M22520/2-01 M22520/2-09 M81969/1-04 M22520/2-08 M81969/1-02
Positronic 9507 9502-3 M81969/1-04 9502-5 M81969/1-02
ITT Cannon 995-0001-584 995-0001-739 N/A 995-0001-604 980-2000-426
AMP 601966-1 601966-6 91067-1 601966-5 91067-2
Daniels AFM8 K42 M24308/18-1 K13-1 M24308/1-02
Astro 615717 615725 M81969/1-02 615724 M81969/1-02
1.3.2 Post Installation Summary
1) Prior to power-up review correct wiring by using standard ohmmeter and
voltage checks. Insure the correct orientation and positioning of the three
SN3500 ‘D’ connectors. The connector numbers are printed on the back
of the SN3500 for reference.
2) Review special items such as connection of the NAV receiver resolver
wiring.
3) Apply power to the SN3500, bring up in maintenance mode and
sequentially access each SN3500 maintenance page to correctly select
the installed equipment.
4) Perform Ground Test procedures
5) Perform Flight Test procedures.
1.4 Interface Planning
1.4.1 Compass System
Determine whether the SN3500 is to be used internally slaved or unslaved.
Unslaved operation would be appropriate when the SN3500 is bootstrapped to an
already slaved compass system or is being slaved to a panel mounted DG with
bootstrap output.
Plan for:
High Resolution Digital Output from a Mid-Continent 4305 series DG with
gyro valid output, flux gate 10 Vac Fluxgate Excitation and Internal 26Vac
Inverter (internal slaving)

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82005-IM-K Sandel SN3500 Installation Manual Page 1-4
Quadrature stepper motor drive input from a Bendix/King KG 102 series
DG with compass valid output and flux gate connected directly to SN3500
(internal slaving).
3-wire ARINC 407 synchro DG with or without gyro valid output and
fluxgate. (internal slaving)
3-wire ARINC 407 synchro remote or panel mounted DG self-slaved with
or without gyro valid output. (SN3500 unslaved)
ARINC 429 Heading Input from AHRS. Sandel monitors for Label 320,
Magnetic Heading Data and Label 270 System Status (SN3500 unslaved)
Internal slaving requires connection of the flux gate excitation to the SN3500 flux gate
reference input P2-24. This input is used only to demodulate the flux gate signals.
DG’s with XYZ bootstrap outputs require the master 400Hz inverter to be connected
to the SN3500 400Hz reference input on P1-16. This input is used to lock all 400Hz
inputs on P1 and 400Hz outputs in the SN3500. This input presents no loading to the
source.
Follow the information on the installation drawings, and plan to set up the appropriate
compass selections on the compass system maintenance page.
Internal slaving does not require the use of an external slaving accessory. Compass
calibration is performed using the SN3500 Compass maintenance page. The
SN3500 will provide standby heading operation from the flux gate alone in the event
of directional gyro (DG) failure.
The SN3500 has a 3-wire ARINC 407 synchro bootstrap compass output if required
which is capable of driving electronic loads.
1.4.2 Autopilot Switching
The SN3500 has low level deviation and flag outputs intended to drive an autopilot.
These outputs feed from the pilot selected navigation source. These outputs may
eliminate the need for an external autopilot switching relay.
However if an external switching relay is used (for instance for compatibility with an
existing installation) the SN3500 has protected Open Drain relay output discretes
intended to drive external switching relays. These outputs have 250ma maximum
current and pull to within 1 ohm of ground.
NAV1 selection is the default selection and no relay driver output discrete is available.
The NAV2, GPS-1, or GPS-2 outputs can be used to operate a switching relay for
each source, allowing the pilot to control the NAV source selection from the front
panel of the SN3500. This is referred to as “master” mode and it is the preferred
mode of installation. In this configuration an additional remote switch/annunciator
panel for a GPS receiver is not required.
In the event the aircraft has an existing GPS switch/annunciator panel or it is desired
that one be installed, the “GPS SELECTED-” input on the SN3500 is used to remote

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82005-IM-K Sandel SN3500 Installation Manual Page 1-5
sense the selection of the GPS1 and annunciate the selection. This is referred to as
“slave” mode. It allows annunciation of the selection on the SN3500 but does not use
the front panel NAV switch to select the GPS receiver. This mode is only available for
use with a single GPS.
Master/Slave mode selection is done in the NAV maintenance page.
When any relay is used, the SN3500 uses a wraparound RELAY SENSE input,
which provides feedback of failure of the switching relay. A pole on the external relay
is used to ground an SN3500 input pin when the relay is in the energized position. If
the low signal is not detected, the SN3500 annunciates the relay failure by redlining
the NAV source display.
1.4.3 Autopilot Course and Heading Datum
Course and heading datum outputs are provided. These can be selected to be AC or
DC in the Flight Control System (FCS) maintenance page and depending on whether
Datum Excitation is connected. The direction sense of these signals can be reversed
as required.
A Back-course discrete output is provided for annunciation or AFCS reverse-course
control when required. This operates during LOC operation when the aircraft is flying
with the tail of the Course Pointer up.
For older Century autopilots a Datum Excitation (5Khz) input is provided. However,
an external transformer coupler must be fabricated. See installation drawings.
1.4.4 GPS Annunciators
For receivers without serial communication capability, discrete annunciator inputs are
provided for ARM, ACT, WPT or HLD, MSG, OBS/LEG Mode, and Parallel Track.
Connect the pins appropriate to the installed receiver and select the receiver type on
the LNAV maintenance page. See GPS/SWITCH/ANNUNCIATORS Installation
drawing for the complete matrix of outputs and annunciators.
Discrete control outputs are provided for APPR ARM, OBS Mode (King KLN90) and
HOLD (II Morrow). These are open-drain outputs.
The Garmin GNS receivers use ARINC 429 for the annunciator functions so no
discrete connections are used.
1.4.5 VLOC Navigation – Internal NAV Converter
For new installations that do not already have an external NAV converter, the
SN3500 supports internal demodulation of composite NAV and Localizer to supply
the display and autopilot outputs with L/R deviation and course selection. See the
appropriate installation drawings.
1.4.6 VLOC Navigation – External NAV Converter

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82005-IM-K Sandel SN3500 Installation Manual Page 1-6
The SN3500 has a single, conventional set of low level analog inputs for deviation,
flags, etc. from a primary NAV receiver. See the installation diagram for details.
These inputs are not used when the Garmin GNS430/530 ARINC NAV receiver,
which uses ARINC 429 only, is being used. If more than one receiver is used which
has analog signaling, this will require switching relays to feed the single set of
SN3500 inputs. Deviation only NAV converters not providing bearing information are
supported.
There are only low level flag inputs. If it is desired to use a Superflag instead of a low-
level flag from the NAV receiver, a series resistor must be used to the low level ‘+’
input and the ‘-‘ input is grounded. See the installation drawings.
Optional ILS lockout of the GPS selection is provided by an ILS Energize 1/2 input
pins. This feature can be disabled on the NAV maintenance page. In the Master
mode this will cause the SN3500 to revert to and annunciate NAV1 when an ILS is
tuned on NAV1, or NAV2 when an ILS is tuned on NAV2. Disabling of ILS lockout is
called for when the customer does not want ILS lockout operation, or when a GPS
receiver with vertical guidance is used to drive the ILS Energize pin during GPS
operation. In this situation NAV1/GPS1 use ILS Energize 1, and NAV2/GPS 2 use
ILS Energize 2 to display vertical guidance.
For analog receivers, two types of resolvers are supported.
a) An electronic OBS resolver with rotor input and SIN/COS outputs is
provided. An associated DC reference pin must be connected to the stator
low-side connection of the NAV receiver. This may be ground but may
also be a DC reference voltage of approximately 4.5vdc. WARNING: You
must check the NAV receiver wiring before installation planning and before
applying power to the system to prevent NAV receiver damage from
inadvertent miswiring. Refer to the Sandel installation drawing.
This resolver will operate from 30Hz to 500Hz and is calibrated in the NAV
maintenance page.
b) An electronic 400Hz differential resolver is provided for use with 400Hz
receivers such as Collins VIR-30A. This interconnect uses SIN/COS
inputs (Z-ground referenced) and SIN/COS outputs (Z-ground referenced).
1.4.7 Marker Beacon
Three inputs are provided for a Marker Beacon repeater. These are DC level-
sensitive inputs. The thresholds and logic levels are adjusted by selection of the
appropriate equipment type on the MKR maintenance page. Lamp load resistors are
internal.
The SN3500 can also monitor label 222 when marker beacon data is provided from
an ARINC 429 source.
1.4.8 Bearing Pointers (VOR, ADF, and TACAN)

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-7
The bearing pointers can derive their information from any of the connected
navigation receivers, including two composite NAV inputs, ADF’s, TACAN’s, and the
long range navigation receivers through the serial ports.
ADF’s can be connected as ARINC 407 synchro or DC SIN/COS inputs. See the
installation drawings for interconnection data and select the appropriate format from
the ADF maintenance page.
The composite NAV inputs accept standard 0.5v ARINC inputs. For 3v inputs a
series resistor is required, please see the appropriate installation drawing. Selection
of 0/180 phase is made by the appropriate maintenance page calibration.
1.4.9 ARINC Channels
The SN3500 contains universal inputs capable of communicating with ARINC 429,
ARINC 419, RS232 and Analog. All equipment capable of ARINC compatibility (such
as GPS/FMS, Navigation, Traffic, etc) can be directly connected to the appropriate
signal input. There are a total of 17 compatible ARINC inputs.
1.4.10 DME Interface
DME inputs support ARINC 429, ARINC 568, King serial, or analog (40mV/mile)
inputs. Analog DME is supported only in software versions 2.01 or higher.
1.4.11 Special Considerations for GARMIN GNS430/530 Series
Required SN3500 Setup Items
Maintenance
Page Items
Study the Sandel Maintenance Page Items on the appropriate GNS430
installation drawings, and set as indicated.
Relay Mode MASTER
ILS Lockout OFF
Required GARMIN GNS430 Setup Items, Receiver 1
Software Main 1.00 or later
IN 1: Low, Sandel SN3500
OUT: Low, GAMA 429 Grph w/Int Note: NOT ARINC 429!
Main ARINC 429
Configuration
SDI: LNAV1 SDI1
Speed RX: Low
Speed TX: Low
VOR/LOC/GS
ARINC 429
Configuration
SDI: VOR/ILS 1 SDI1
Required GARMIN GNS430 Setup Items, Receiver 2

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-8
Software Main 1.00 or later
IN 1: Low, Sandel SN3500
OUT: Low, GAMA 429 Grph w/Int Note: NOT ARINC 429!
Main ARINC 429
Configuration
SDI: LNAV2 SDI2
Speed RX: Low
Speed TX: Low
VOR/LOC/GS
ARINC 429
Configuration
SDI: VOR/ILS 2 SDI2
1.4.12 Special Considerations for UPS GXXX
Configuration Notes:
GX Series Notes: In Setup, enable Extended MovMap Data Format
SN3500 Unit: Set LNAV selection to IIMorrow GX (RS-232 ENH)
Vertical deviation (if desired) requires the ILS ENG input pin pulled low.
Testing The GX unit will not output RS-232 data in manual test mode
Upon power on, the GX will go through IFR Output Test Mode and the
following test can be observed:
CDI & Flags
VDI & Flags (if enabled on Sandel)
Annunciators
1.4.13 Brightness Control
Brightness control is internal through a pilot’s menu. No external brightness buss is
used.
1.4.14 Traffic
The SN3500 supports Traffic input via single ARINC 429 High Speed Input on
software version 2.01 and above. Purchase of a key code to enable the Traffic
display is required.
Some remote traffic processors may require remote switches, see the Traffic
interface drawings in this manual for these requirements.
When interfaced to a TCAS II remote processor, the SN3500 can only be used as a
secondary display as it will not display vertical guidance for the purpose of resolution
advisories.
1.4.15 Data Link Weather
The SN3500 supports Flight Information Services-Broadcast (FIS-B) data link
weather (precipitation and lightening), input via a single RS-232 Input from a WSI
Data Link receiver in software version 3.00 and above. Purchase of a key code to

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-9
enable the weather display is required. See the WSI Data Link Receiver interface
drawings in this manual for interface wiring requirements.
The SN3500 can be configured to operate as the sole weather display or a listener
when another display is installed and configured to command the WSI receiver.
When the SN3500 is the sole display, the WSI receiver RS-232 interface must be
configured as “NO FLOW CONTROL”, see the WSI receiver manual for details
regarding receiver configuration.
1.4.16 TACAN
The SN3500 supports TACAN input via ARINC 419, ARINC 429, and Arinc 407
Synchro (XYZ). A TACAN key code is not required for maintenance page setup
however, purchase of a key code to enable the TACAN display is required. When
configured, TCN will not appear as a NAV source selection or on the bearing pointer
source list if the TACAN key is not valid. See the TACAN interface drawings in this
manual for interface wiring requirements.

General Information
82005-IM-K Sandel SN3500 Installation Manual Page 1-10
1.4.17 Night Vision Support Option
For NVIS capable units NVIS mode is enabled by a closure to ground through an
external toggle switch or maintained pushbutton switch. NVIS mode is annunciated
onscreen so an external annunciator is not required.
The input will always pull up to the de-activated state when disconnected .
1.4.18 Reversionary Attitude Option
The SN3500 supports a Reversionary Attitude Display when interfaced to a Attitude
Heading Reference System supplying Roll, Pitch, Heading , and lateral acceleration
data via Arinc 429. An optional key code is required to enable this feature. See the
Reversionary Control interface drawing in this manual for interface wiring
requirements. This option is not available when the SN4500 is interfaced to an analog
DME.
1.5 Disclaimer
Sandel Avionics does not assume any risk for nor accept any responsibility for the
interface descriptions contained within this Installation Manual. It is the responsibility
of the installer to ensure that such equipment is compatible with the SN3500 as
described, and to ensure that the installation of the SN3500 is accomplished with
such equipment using the specific equipment manufacturer’s installation and
technical instructions. No other representations are expressed herein.

Technical Information
82005-IM-K Sandel SN3500 Installation Manual Page 2-1
2Technical Information
2.1 General
The SN3500 is enclosed in an ARINC 408, 3ATI form factor enclosure and is
mounted to an instrument panel using a standard ATI clamp. A black or grey bezel is
provided.
The SN3500 operates on an input voltage from 22 to 33 Volts DC (11 to 33 volts DC
on units with serial number 5-2500 or higher), nominal 35 watts. One or two 26 Volts
AC, 400 Hertz reference excitation inputs with a current requirement of less than 1
milliampere is required when the functions of AC synchro inputs or outputs are
required for use with peripheral equipment. This reference excitation signals must be
obtained from the aircraft inverter source. A third inverter input (‘Datum Excitation’ is
available specifically used in situations where the autopilot uses an additional inverter
or the autopilot inverter frequency is higher than 400Hz.
The following section describes the technical characteristics that include the
appliance approval basis, physical and electrical properties, electrical connector pin
allocation which details function and gradient or equipment protocol, and ARINC label
support. Also included is the description of the SN3500 installation components,
other equipment and installation requirements. A review of the installation approval
procedures is provided for filing with authorities.
2.2 Part Numbers
The part number for the standard Sandel SN3500 is:
SN3500 - XXX
Major Minor
Variation Variation
The part number for the Sandel SN3500 with NVIS support is:
SN3500 - XXXN
Major Minor
Variation Variation
The current version of software is displayed on the power-up screen.

Technical Information
82005-IM-K Sandel SN3500 Installation Manual Page 2-2
2.2.1 Installation Kit and Accessories
SPN Description
90143 SN3500 installation kit
90124 Bezel Adapter Kit KI-525 Flush (Used to fill
non-standard sized hole in installations
replacing a KI-525 indicator.)
90130-LK Lamp Kit (Replacement lamp for lamp units)
2.2.2 Bill of Materials – SN3500 Install Kit
SPN Description Qty
32062 Conn., D- 15 with pins (Positronics P/N SD15F10JVLO) 1
32063 Conn., D-44 with pins (Positronics P/N DD44F10JVLO) 2
60144 Shim Flush Mounting 1
61062 3ATI Mounting Clamp 1
82005-IM Installation Manual, SN3500 1
88114 USB Cable 1
2.3 Approval Summary
2.3.1 License Requirements
None.
2.3.2 Approval Data
Technical Standard Order: TSO-C113, “Airborne Multipurpose Electronic Displays”
TSO-C3d, “Turn and Slip Instrument”
TSO-C4c, “Bank and Pitch Instruments”
TSO-C6d, “Direction Instrument, Magnetic
(Gyroscopically Stabilized)
TSO-C34e, “ILS Glide Slope Receiving Equipment
Operating Within The Radio Frequency Range of 328.6-
335.4 Megahertz”
TSO-C35d, “Airborne Radio Marker Receiving
Equipment”
TSO-C36e, “Airborne ILS Localizer Receiving Equipment
Operating Within The Radio Frequency Range of 108-
112 Megahertz”