Avionics / Encoders, Altitude / Trans-Cal / Trans-Cal Altitude Encoder Model Ssd120-35C-Rs232 FAA TSO-C88 Trans-Cal Altitude Encoder Model Ssd120-35C-Rs232 FAA TSO-C88 Installation Manual
Trans-Cal Industries, Inc.
Altitude Encoder/Digitizer
Owner / Installation Manual Model SSD120-35C-RS232
FAA TSO-C88a Approved
EASA ETSO-C88a Approved
Trans-Cal Industries, Inc.
16141 Cohasset St.
Van Nuys, CA 91042
(818)787-1221 FAX (818)787-8916
www.trans-cal.com
28 June 2016 881625 Rev. A
Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Copyright Notice: This document may not be reproduced, transmitted, or copied in any form without
the prior written consent of Trans-Cal Industries, Inc. The data contained herein is subject to change
without notice. Trans-Cal Industries hereby grants permission to download one copy of this manual
and any subsequent revision, provided that electronic or printed copy contains this complete
copyright notice. Trans-Cal Industries explicitly prohibits any unauthorized commercial distribution of
this manual or any revision thereto.
© 2016 by Trans-Cal Industries, Inc.
16141 Cohasset Street
Van Nuys, CA 91406
CAGE Code 57323
818/787-1221
FAX 818/787-8916
E-Mail: support@trans-cal.com
www.trans-cal.com
What’s in the Box:
Qty. Part Number Description
1 SSD120-35C-RS232 Altitude Digitizer with RS232 Outputs
1 881625 Owner/Installation Manual
1 DA-15S 15-Pin D-Subminiature Mating Connector
1 600016 15-Pin Connector Back Shell
1 600019 1/8NPT Nylon Tube Fitting
1 600020 ¼” Tube Tee Fitting
1 881616 Tray
1 881023-3 Knob
History of Revision
Revision
Date Description
A 28 June 2016 Production Release
Reference Publications
• EASA ETSO-C88a Automatic Pressure Altitude Code Generating Equipment
• FAA Advisory Circular 43-6C Altitude Reporting Equipment and Transponder System Maintenance and
Inspection Practices
• FAA TSO-C88a Automatic Pressure Altitude Code Generating Equipment
• FAR 23.1325 Static Pressure System
• FAR 43-Appendix E, Altimeter System Test and Inspection
• FAR 43-Appendix F ATC Transponder Tests and Inspections
• FAR 91.217 Data Correspondence Between Automatically Reported Pressure Altitude Data and the
Pilot's Altitude Reference
• FAR 91.411 Altimeter System and Altitude Reporting Equipment Tests and Inspections
• RTCA/DO-160E Environmental Conditions and Test Procedures for Airborne Equipment
• RTCA/DO-178 Software Considerations in Airborne Systems and Equipment Certification
• SAE AS8003 Minimum Performance Standard for Automatic Pressure Altitude Reporting Code
Generating Equipment
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table of Contents
History of Revision .................................................................................................................. 2
Reference Publications ........................................................................................................... 2
Table of Contents .................................................................................................................... 3
Safety Notes............................................................................................................................ 5
Abbreviations, Acronyms and Symbols ................................................................................... 6
Section 1.0 Introduction .......................................................................................................... 7
1.1 Scope ............................................................................................................................ 7
1.2 Equipment Description .................................................................................................. 7
1.3 General Specifications ................................................................................................... 7
1.3.1 Limitations, Deviations and Compliance ................................................................. 8
1.3.2 TSO/ETSO/RTCA Certification and Compliance Table .......................................... 8
1.3.3 Operating Altitude ................................................................................................... 8
1.3.4 Accuracy ................................................................................................................. 9
1.3.5 Mechanical Characteristics ..................................................................................... 9
1.3.6 Over Range ............................................................................................................. 9
1.4 Parallel Data Port Specifications ................................................................................... 9
1.5 Serial Altitude Data Port Specifications ....................................................................... 10
1.6 Configuring the Serial Data Output .............................................................................. 10
1.7 Serial Port Altitude Data Resolution ............................................................................ 11
1.8 Serial Communication Format ..................................................................................... 11
1.9 Serial Communication Protocol ................................................................................... 12
1.9.1 UPS AT/Garmin AT/IIMorrow Nav. Devices ......................................................... 12
1.9.2 Trimble Garmin Navigation Devices Protocol ....................................................... 12
1.9.3 Northstar Navigation Devices Protocol ................................................................. 13
1.9.4 Magellan Navigation Devices Protocol ................................................................. 13
1.9.5 ARNAV Systems Protocol ..................................................................................... 14
1.9.6 UPS AT 618 Loran Devices Protocol (IIMorrow) .................................................. 14
Section 2.0 Operation ........................................................................................................... 15
2.1 General ........................................................................................................................ 15
2.2 Operating Instructions ................................................................................................. 15
2.3 Time to Altitude Data Enable ....................................................................................... 16
Section 3.0 Installation .......................................................................................................... 17
3.1 Mechanical Installation ................................................................................................ 17
3.2 Electrical Installation .................................................................................................... 18
3.3 Serial Altitude Data Port Test Equipment .................................................................... 19
3.4 Parallel ICAO Altitude Data Port Test Equipment ....................................................... 19
Section 4.0 Calibration and Configuration ............................................................................. 20
4.1 Calibration Overview ................................................................................................... 20
4.2 Required Equipment Span Adjust ............................................................................... 21
4.3 Span Adjust Procedure ................................................................................................ 21
4.4 Dynamic Calibration Adjustment Procedure using the ECP-100 ................................. 24
4.5 Calibration Wiring Harness Using the ECP-100 .......................................................... 26
4.6 Calibration Harness Using a PC with RS232 Input ..................................................... 26
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4.7 Serial Data Offset ........................................................................................................ 28
4.8 Serial Port Software Configuration Using the ECP-100 .............................................. 29
Section 5.0 Digitizer Interconnection Tables ......................................................................... 31
Table I Bendix King ........................................................................................................... 31
Serial Data Connection for the Bendix/King KT 73 & KT 74 Transponder ........................ 31
Table II Cessna, Narco, Microair ....................................................................................... 32
Table III Garmin ................................................................................................................. 33
Table IV Garmin ................................................................................................................ 34
Table V Garmin ................................................................................................................. 34
Table IVI Edo-Air, Genave, Collins, Radair ....................................................................... 35
Table VII Bendix, Wilcox, UPS AT .................................................................................... 36
Table VIII UPS AT ............................................................................................................. 36
Table IX Becker, Terra ...................................................................................................... 37
Table X Trig, Avidyne ........................................................................................................ 37
Table XI Bendix King EGPWS .......................................................................................... 38
Table XII NavWorx ADS600-B .......................................................................................... 39
Table XIII NavWorx ADS600-EXP .................................................................................... 39
Table XIV Connector Pin Assignments SSD120-35C-RS232 ........................................... 40
Table XV Quick Guide to Common Serial Data Interconnects .......................................... 41
Section 6.0 GPS/MFD & Miscellaneous Connection Data .................................................... 42
Table XVI Apollo GX Series .............................................................................................. 42
Table XVII Apollo MX20 .................................................................................................... 42
Table XVIII Trimble ............................................................................................................ 43
Table XIX Trimble .............................................................................................................. 43
Table XX Garmin ............................................................................................................... 44
Table XXI Garmin .............................................................................................................. 44
Table XXII ARNAV ............................................................................................................ 45
Table XIII ARNAV .............................................................................................................. 45
Table XIV ARNAV ............................................................................................................. 45
Table XXV Century Flight Systems ................................................................................... 46
Section 7.0 Instructions for Continued Airworthiness ........................................................... 47
Section 8.0 Adapter Plate Ordering Information ................................................................... 47
Section 9.0 Frequently Asked Questions .............................................................................. 48
Section 10.0 Known Compatibility Issues ............................................................................. 50
10.1 Narco Older Transponders and the SSD120-35C-RS232 ........................................ 50
10.2 King KT-75 ................................................................................................................ 50
10.3 S-Tec (Collins) TDR-950 ........................................................................................... 51
10.4 Trans-Cal SSD120-35C-RS232 Backwards Compatibility ........................................ 51
10.5 SSD120-35C-RS232 Compatibility to Competitor’s Products ................................... 51
Outline Drawing .................................................................................................................... 53
Environmental Qualification Form ......................................................................................... 54
Part Number Builder ............................................................................................................. 55
Manufacturer Direct Warranty ............................................................................................... 56
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table of Figures
Figure 1 Parallel Code Transitions .......................................................................................... 9
Figure 2 Cover Removal and Configuration Shunt Location ................................................. 10
Figure 3 Cover Removed ...................................................................................................... 11
Figure 4 Configured for UPS AT ........................................................................................... 12
Figure 5 Configured for Trimble with 10' Resolution ............................................................. 12
Figure 6 Configured for Northstar with 10’ Resolution .......................................................... 13
Figure 7 Configured for Magellan with 10’ Resolution .......................................................... 13
Figure 8 Time to Altitude Data Enable .................................................................................. 16
Figure 9 Serial Data Output Pins .......................................................................................... 19
Figure 10 Low & High Calibration Adjustments ..................................................................... 22
Figure 11 Span Adjust Block Diagram ................................................................................. 23
Figure 12 Dynamic Calibration Set-Up .................................................................................. 25
Figure 13 Digitizer Correspondence ..................................................................................... 27
Figure 14 Serial Data Offset .................................................................................................. 28
Figure 15 Serial Port Configuration Using the ECP-100 ....................................................... 30
Figure 16 DA-15P D-Subminiature Connector Front View .................................................... 40
Safety Notes
CAUTION! INCORRECT TOOLING OR TEST EQUIPMENT CAN RESULT IN
DAMAGE TO THIS INSTRUMENT AFFECTING ITS AIRWORTHINESS.
This manual calls out chemicals and other commercially available materials. The installer
must obtain the Material Safety Data Sheets from the manufacturer or supplier of the
materials. It is the installer’s responsibility to know and follow the procedures,
recommendations, warnings and cautions set forth for the safe use, handling, storage and
disposal of the materials.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
C
V
V
L
Abbreviations, Acronyms and Symbols
A
AC
ADS-B
ARINC
ASCII
ATCRBS
bps
CAGE
CFR
R
EASA
EEPROM
EIA
ESDS
ETSO
FAA
FAR
ft.
GPS
H/W
Hz
ICAO
I.F.F.
In. Hg.
Kbps
KHz
F
LSB
M
mA
Amperes
Advisory Circular
Automatic Dependent SurveillanceBroadcast
Aeronautical Radio Incorporated
American Standard for Coded
Information Interchange
Air Traffic Control Radar Beacon
System
Bits per second.
Commercial and Government Entity
Code of Federal Regulations
Carriage Return
European Aviation Safety Agency
Electronically Erasable Read Only
Memory
Electronic Industries Association
Electrostatic Discharge Sensitive Device
European Technical Standard Order
Federal Aviation Administration
Federal Aviation Regulation
Distance in feet.
Global Positioning System
Hardware
Hertz
International Civil Aviation Organization
Identification Friend or Foe
Pressure in Inches of Mercury
Kilobits per Second
Kilohertz
Line Feed
Least Significant Bit
Distance in Meters
Milliamperes
max.
MB
MHz
MFD
MM
MSL
min.
ms
MSB
mW
NIST
oz
P/N
psi
RAM
RS
RTCA
SAE
sec.
SSR
S/W
TCI
TIA
TSO
dc
SI
W
Ω
ºC
±
Maximum
Millibar
Megahertz
Multi-Function Display
Distance in Millimeters
Mean Sea Level
Minimum
Time in milliseconds.
Most Significant Bit
Milliwatt
National Institute of Standards and
Technology
Ounce
Part Number
Pounds per Square Inch
Random Access Memory
Recommended Standard
Radio Technical Commission for
Aeronautics
Society of Automotive Engineers
Time in seconds.
Secondary Surveillance Radar
Software
Trans-Cal Industries, Inc.
Telecommunication Industries
Association
Technical Standard Order
Volts Direct Current
Vertical Speed Indicator
Watt
Electrical resistance measured in Ohms.
Temperature in degrees Celsius.
Plus or minus.
ESD Caution Caution
Electrical Hazard
Do Not Expose To Moisture
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Section 1.0 Introduction
1.1 Scope
This manual provides detailed installation, calibration and operating instructions for
Trans-Cal Industries’ Model SSD120-35C-RS232 series of altitude encoder/digitizer.
This manual assumes use by competent, qualified avionics professionals utilizing
installation methods in accordance with 14 CFR and other industry accepted
installation practices.
1.2 Equipment Description
Approved under FAA TSO-C88a and EASA ETSO-C88a the Model SSD120-35CRS232 is an all solid-state electronic device which, when connected to an aircraft
static and electrical system, converts pressure altitude information into parallel and
serial digital data.
The parallel digital altitude data protocol is set forth in the ICAO International
Standard for SSR Pressure Altitude Transmission. In accordance with U.S. National
Standards for Common System Component Characteristics for the I.F.F. Mark X
(SIF)/Air Traffic Control Radar Beacon System SIF/ATCRBS.
The serial altitude data is provided on (2) two asynchronous RS232 outputs. The
serial data protocol is selectable and may be used to provide pressure altitude data
to GPS or other on board navigation devices.
1.3 General Specifications
Operating Voltage:
Model SSD120-35C-RS232
Operating Current all models: 0.25 Amps at 14Vdc
Operating Temperature:
Model SSD120-35C-RS232
Storage Temperature (non-operating)
Warm-up time: 0 Seconds at 20°C (68°F). See Figure 9 for
Weight: 4.3 oz. (5.3 oz. with tray and knob)
+12 to 30 Vdc
0.27 Amps at 28Vdc
-20° to +55°C (-4° to +158°F)
-65° to +85°C (-85° to +185°F)
low temperature warm-up times.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
1.3.1 Limitations, Deviations and Compliance
Note:
The conditions and tests for TSO approval of this article are minimum
performance standards. Those installing this article, on or in a specific type or
class of aircraft, must determine that the aircraft installation conditions are within
the TSO standards. TSO articles must have separate approval for installation in
an aircraft. This article is to be installed in accordance with 14 CFR part 43 or the
applicable airworthiness requirements.
Note:
DO-160E lightning induced transient susceptibility tests were not conducted on
this device and it is the responsibility of the installing agency to substantiate
compliance with FAR 25.1316. Advisory Circular AC 20-136B provides guidance
related to the protection of aircraft electrical systems from the effects of lightning.
Deviation:
TSO-C88a specifies RTCA/DO-160A for environmental testing. TCI utilized
RTCA DO-160E in testing this device. DO-160E provides an equivalent level of
safety and meets or exceeds the standard environmental test condition
requirements of TSO-C88a and DO-160A.
1.3.2 TSO/ETSO/RTCA Certification and Compliance Table
FAA TSO
EASA TSO
RTCA DO-178 Software
C88a
C88a
Non-Essential Category
H/W - S/W P/N: 881603rA-700001rC
RTCA DO-160E
D1BAB[(SM)(UF)]XXXXXXZBBB(BC)TTBXXXAX
Environmental*
*See environmental Qualification Form for Specifics.
1.3.3 Operating Altitude
Model Operating Altitude
SSD120-35C-RS232 -1000 to +35,000 feet.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
1.3.4 Accuracy
Digitizer accuracy is ±50 feet from -1000
to +30,000 feet, and ±75 feet from
30,100 to +35,000 feet, when measured
from the altitude transition points of the
ICAO code and referenced to 29.92 In.
Hg. (1013 MB.) See Figure 1 and §4.0.
Figure 1 Parallel Code Transitions
1.3.5 Mechanical Characteristics
Model Number Dimensions Weight
Model SSD120-35C-RS232
See Outline Drawing
Tray 881616 and knob 881023 adds 1 oz. to weights above.
1.3.6 Over Range
The SSD120-35C-RS232 series of altitude digitizers will not be damaged when
operated beyond their specified maximum altitude up to 100,000 feet MSL,
(0.1581psi) or over pressured to –5721 feet (18psi) maximum.
1.4 Parallel Data Port Specifications
Code Format: In accordance with U.S. National Standard for Common System
Component Characteristics for the IFF Mark X (SIF) Air Traffic Control Radar Beacon
System, SIF/ATCRBS.
Driver Description: The parallel altitude data output is provided by the “uncommitted”
collectors of a transistor array and must be “pulled-up” through a resistive load by the
transponder.
Pull-Up Voltage: +3 to 40Vdc.
Maximum Sink Current: 50 mA.
Maximum Cable Length: 4000 ft. (1219 meters)
Input Signal Requirement: Pin 6 (strobe or signal common) must be either
grounded or connected to the transponder.
4.3 oz.
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1.5 Serial Altitude Data Port Specifications
Electrical Format: Conforming to the TIA/EIA RS-232C standard.
Logic Levels: “0”, +9 Vdc. Logic “1”, -9 Vdc.
Driver Output Maximum Voltage: ±25 Vdc.
Driver Load Impedance: 3KΩ typ.
The RS232E standard recommends one receiver per serial port.
Maximum Cable Length: 50 Feet. (15.24 meters)
Code Format: ASCII
Communication System: Simplex
Transmission Method: Asynchronous. (Talk only.)
Baud Rate: Selectable, 1200 bps to 9600 bps.
Transmission Rate: 1/sec.
1.6 Configuring the Serial Data Output
The SSD120-35C-RS232 must be configured through a series of shunts to transmit
the correct serial data protocol. These shunts are found under the cover of the unit
and allow changes to the serial data resolution, message and baud rate. Remove the
four screws and cover to access the shunts. See Figure 2. The serial port protocol
may also be configured via RS232 communication. See §4.8
DISCONNECT POWER PRIOR
CAUTION
OBSERVE PRECAUTIONS FOR
HANDLING ELECTROSTATIC
SENSITIVE DEVICES!
CAUTION
Figure 2 Cover Removal and
Configuration Shunt Location
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Figure 3 Cover Removed
JP1 Header SSD120-35C-RS232 Configuration Shunts
Always open Model SSD120-35C-RS232
J1
Always closed Model SSD120-35C-RS232
J2
Always closed Model SSD120-35C-RS232
J3
Close for 10’ resolution serial data.
J4
Open for 100’ resolution data.
Protocol See §1.9
J5
Protocol See §1.9
J6
1.7 Serial Port Altitude Data Resolution
The default resolution of the altitude digitizer serial data is 100 feet. To enable 10foot resolution, close J4 of the JP1 Header. The serial port resolution may also be
configured via software. See §4.8. and Figure 3.
1.8 Serial Communication Format
Model SSD120-35C-RS232 carries out serial communication asynchronously with
the “Start/Stop” system. The specifics of the format i.e., the number of data bits,
baud rate etc., is determined by the protocol selected. As shipped from the factory,
the default protocol is the UPS message at 1200bps, 8 data bits, 1 stop bit and no
parity.
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1.9 Serial Communication Protocol
Serial data protocol is user selectable by using shunts to close or open J5 and J6 of
the JP1 Header, or by selecting protocols via software. See §4.8, refer to FIGURES
4 through 7.
CAUTION! DISCONNECT ELECTRICAL POWER BEFORE REMOVING
THE COVER.
CAUTION! OBSERVE PRECAUTIONS FOR ELECTROSTATIC
SENSITIVE DEVICES.
CAUTION! DO NOT EXPOSE THIS DEVICE TO MOISTURE.
1.9.1 UPS AT/Garmin AT/IIMorrow Nav. Devices
Leaving J5 and J6 of the JP1 Header open results in a protocol compatible
with UPS Aviation Technologies’ (IIMorrow) Navigation devices. The Digitizer
will send a seventeen byte message beginning with # AL, then a space
followed by five altitude bytes, the letter “T”
and the sensor temperature, two checksum
bytes and a carriage return. (1200bps, 8 data
bits, 1 stop bit, no parity) The following is an
example of the serial message accepted by
some UPS AT (Garmin AT) (IIMorrow)
devices
Message Definition
#AL +00800T+25D9
C
Altitude 800 feet
R
Figure 4 Configured for UPS AT
with 10’ Resolution
1.9.2 Trimble Garmin Navigation Devices Protocol
Closing J6 and leaving J5 open on the JP1 Header results in a protocol
compatible with some Trimble and Garmin devices. The Digitizer will send a
ten-byte message. The message begins with ALT followed by a space and
five altitude bytes, concluding with a carriage return. (9600bps, 8 data bits, 1
stop bit, no parity) The following are examples
of serial messages accepted by some Trimble,
Garmin and Bendix/King devices:
Message Definition
ALT -9900
ALT 10500
C
Digitizer disabled.
R
C
Altitude 10,500 feet
R
Figure 5 Configured for Trimble with 10'
Resolution
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1.9.3 Northstar Navigation Devices Protocol
Closing J5 and leaving J6 open on the JP1 Header results in a protocol
compatible with some navigation devices manufactured by Northstar and
Garmin. The Digitizer will send a 10-byte message. The message begins with
ALT followed by a space and five altitude bytes; concluding with a carriage
return. (2400bps, 8 data bits, 1 stop bit, no parity.) The following are examples of
serial messages for these devices:
Message Definition
ALT 02500
ALT -2500
C
Altitude 2500 feet.
R
C
Digitizer disabled
R
Figure 6 Configured for Northstar with 10’
Resolution
1.9.4 Magellan Navigation Devices Protocol
Closing both J5 and J6 on the JP1 Header results in a protocol compatible with
some navigation devices manufactured by Magellan. The Digitizer sends a
seventeen-byte message beginning with $MGL, followed by a +/- sign and five
altitude digits, then T+25, a checksum and concludes with a carriage return.
(1200bps, 7 data bits, 1 stop bit, even parity.) The following is an example of a
serial message for Magellan devices:
$MGL+02500T+250C
Message Definition
C
Altitude 2500 feet
R
Figure 7 Configured for Magellan with 10’
Resolution
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1.9.5 ARNAV Systems Protocol
Leave pins J5 and J6 of the JP1 Header open, the ARNAV Systems protocol
MUST be software selected. See §4.8 for protocol selection details. Once
selected, the Digitizer will send a 24-byte message. Beginning with a ASCII code
02 = STX (Start of Text) then $PASHS followed by a comma and ALT, then a +/sign followed by five altitude digits (in meters,) then an asterisk and a checksum
followed by a carriage return and a line feed. Concluding with an ASCII code 03
= ETX (End of Text). (9600bps, 8 data bits, 1 stop bit, no parity.) The following is
an example of an ARNAV serial altitude message:
Message Definition
STX$PASHS,ALT,+00033*1B
CRL
ETX Altitude 33 meters
F
1.9.6 UPS AT 618 Loran Devices Protocol (IIMorrow)
Leave pins J5 and J6 of the JP1 Header open, the UPS AT 618 Loran devices
protocol MUST be software selected. See §4.8 for protocol selection details.
Once selected, the Digitizer will send a seventeen byte message beginning with
# AL, then a space followed by a positive/negative sign, five altitude bytes; the
letter “T” and the number “25”; two checksum bytes and a carriage return.
(1200bps, 7 data bits, 1 stop bit, odd parity). The following is an example of an
UPS AT 618 Loran serial altitude message:
#AL +00800T+25D9
Message Definition
C
Altitude 800 feet
R
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Section 2.0 Operation
2.1 General
The SSD-12035C-RS232 series of altitude digitizers are designed to be mounted within
a pressurized or non-pressurized, but temperature controlled area within aircraft
operating up to 35,000 feet MSL. Usually remotely located, the digitizer is fully automatic
in operation. The parallel data output is controlled by the transponder while the serial
altitude data is transmitted asynchronously. (Half duplex, talk only. Full duplex in
calibration and configuration modes only.)
2.2 Operating Instructions
Parallel Data:
Place the transponder in mode “C”, altitude-reporting mode, and apply power to the
transponder and to the digitizer. In some installations the digitizer will automatically be
supplied power when the transponder is energized. In other installations, power to the
digitizer may be through a separate circuit breaker. If power to the digitizer is provided
directly from the aircraft’s avionics buss, follow the power-up procedures recommended
by the transponder manufacturer. All parallel outputs will be pulled low for a self-test (3
seconds) at power up, then assume the value for the present input pressure.
NOTE: A short warm-up time may affect the actual data enable time. Typically, at 0ºC a
one-minute period is required before the data will enable. See §2.3 & Figure 8.
In some installations, the transponder controls the digitizer by enabling and disabling its
output. In other installations, the digitizer’s output is not controlled by the transponder
and is continuously enabled, (Digitizer pin 6 is grounded.)
Serial Data:
The serial communication is fully automatic and transmission begins after the self-test is
complete. Strobing (pin 6) the parallel data output of the digitizer will not affect the serial
data transmission.
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2.3 Time to Altitude Data Enable
The altitude digitizer requires a warm-up time for its pressure sensor to reach operating
temperature prior to enabling its output. This time to data enable will vary based on the
ambient temperature and the supply voltage as shown in Figure 8.
Figure 8 Time to Altitude Data Enable
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Section 3.0 Installation
3.1 Mechanical Installation
The SSD120-35C-RS232 should be installed in a manner consistent with the
requirements of 14 CFR part 43. Good workmanship and installation practices in
accordance with the instructions given in this publication are to be observed. To verify
the digitizer has been properly and safely installed, the installer should perform a visual
inspection and conduct an overall operational check of the system prior to flight.
The SSD120-35C-RS232 series of digitizer may be mounted in any attitude within the
internal structure of the aircraft. DO NOT mount the digitizer in any location that could
interfere with the safe operation of the aircraft. DO NOT mount the digitizer in the direct
air stream of either hot or cold air ducts. The mounting position should allow for a short
static pressure line from the digitizer to the altimeter, access to the digitizer’s
adjustments, and ample room for a service loop for the interconnecting cabling. The
SSD120-35C-RS232 is provided with an 1/8-27NPT static port inlet, used to connect the
digitizer to the aircraft static system. Apply an anti-seize pipe sealant (not included) or
equal to the mating fitting. Exercise care to prevent excess sealant from plugging the
inlet to the pressure sensor. Loctite RTV Clear Silicone Sealant (59530) is
recommended and Is used to seal static line connections during all environmental testing
at Trans-Cal.
Use #4-40 or #6-32 machine screws, sheet metal screws, or rivets to attach the digitizer
or the mounting tray 881616 to the airframe. Secure mating connectors to the digitizer
housing using the #4-40 screws provided. Refer to the Outline Drawing for mechanical
dimensions.
Installations that orient the digitizer in an upside down position utilizing the mounting tray
881616 and knob 103023, will require the use of a few drops of removable Loctite®
Threadlocker 242. Follow the manufacturer’s instructions to apply a few drops into the
knob’s threaded hole then use the knob to secure the digitizer to the mounting tray. The
application of Loctite will ensure that the knob will remain secured and vibration will not
cause the knob to work loose allowing the digitizer to drop down out of the mounting
tray.
Avoid mounting the SSD120-35C-RS232 near any equipment operating with high pulse
currents or high power outputs such as strobe power supplies, radar, and or satellite
communications equipment.
To prevent the accumulation of condensation in the digitizer pressure sensor, locate this
device away from the lowest section of the static system, and ensure a proper
condensation trap and system drain is installed and functional, reference FAR 23.1325.
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Verify that moisture resulting from condensation will run away from the digitizer electrical
connections.
Adapter plates are available to convert older Trans-Cal and competing digitizer
installations for use with the SSD120-35C-RS232 series of altitude digitizers. See
ordering information in §8.0.
3.2 Electrical Installation
NOTE: Proper solder or crimp techniques should be observed when attaching wires to
the mating connectors. Failure to do so could result in damage, intermittent operation or
non-operation of the digitizer. Shielded cable is recommended for both serial and parallel
data wiring harnesses. Wire and harnesses should be installed in such a way that the
weight of the cable does not exert a force on the connector pins. Wiring harnesses must
be fully supported to prevent movement and should be protected against chaffing.
CAUTION!
AFTER INSTALLING THE WIRING HARNESS AND BEFORE INSTALLATION
OF THE DIGITIZER, A CONTINUITY CHECK OF ALL WIRES IN THE HARNESS
SHOULD BE MADE TO VERIFY HARNESS CONSTRUCTION. A TEST SHOULD
THEN BE MADE WITH THE AIRCRAFT POWER SUPPLIED TO THE
DIGITIZER’S CONNECTOR TO VERIFY POWER, GROUND AND DATA ARE
ROUTED TO THE CORRECT PINS AS DETAILED IN THE OUTLINE DRAWING
AND TABLE XIV. REMOVE POWER BEFORE INSTALLING THE DIGITIZER.
The digitizer is designed to operate with either a +14 or 28 Vdc power source. These
voltages may be switched power provided by the transponder or may be provided by the
avionics buss. If using the avionics buss, protect the circuit with a ½ amp fuse or circuit
breaker.
Parallel Data Connections - Table XIV and the outline drawing provide electrical
connector pin/function information. Use this data when connecting the digitizer to the
transponder. In some installations where older transponders are used, the transponder
may not provide an “altitude disable” function. In this case, an instrument panel mounted
switch for this function may be required utilizing pin 6 of the digitizer connector.
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Serial Data Connection - Connect the TxD1 (pin 14) or TxD2
(pin 7) from the digitizer
connector to the RxD (receive data) port on the GPS or other receiving device. It is
important to provide a data ground from the digitizer to the receiving GPS or other
device.
Figure 9 Serial Data Output Pins
3.3 Serial Altitude Data Port Test Equipment
The output of the serial port may, or may not be directly displayed by the GPS or other
device receiving the serial data. There are several ways to test the output of the serial
port:
a.) Use a TCI Model ATS-400 Test Set or ECP-100 Programmer to display the
serial altitude data.
b.) Connect to an open serial port on a personal computer using serial data
capture software such as PROCOMM™, VERSATERM™, SOFTWARE
WEDGE™, TERMINAL (Windows® 3.x) or HYPERTERMINAL (Windows®
95, 98, 2000 or XP.)
c.) Use a dedicated serial data test box such as the BLACK BOX™ RS232
Monitor.
d.) Test for serial output using an oscilloscope to view the 9 Vdc square wave
group transmitted about twice a second.
3.4 Parallel ICAO Altitude Data Port Test Equipment
The output of the parallel ICAO altitude data may be monitored by any number of
transponder ramp test sets, which allow display of the ICAO altitude digitizer/encoder code.
The IFR Model ATC-600A Portable Transponder Test Set is one example. Alternatively, the
Trans-Cal Industries’ ATS-400 or EET-200 may be used to display the parallel data directly
from the digitizer.
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Section 4.0 Calibration and Configuration
4.1 Calibration Overview
Reference Documents: FAR 91.217; FAA Advisory Circular 43-6C
FAR 91.411; FAR 43-Appendix E and F
FAA TSO-C88a, EASA ETSO-C88a, SAE AS8003
NOTE: To ensure correspondence with all on-board pressure altitude systems,
altitude digitizers that are not providing information to the ATC transponder
should be tested to ensure correspondence to the primary flight altimeter, as per
FAA AC 43-6C.
The following procedures will allow adjustment to the calibration curve of the SSD12035C-RS232 or as an aide in matching the digitizer output to a primary flight altimeter or
NIST traceable pressure standard.
The maximum allowed error between the primary flight altimeter and the altitude digitizer
is ±125 feet as required by TSO-C88a and ETSO-C88a. All Trans-Cal digitizers are
calibrated to within ±50 feet of a NIST traceable pressure standard; however, the error
allowed on flight altimeters at higher altitudes can lead to a combined error in excess of
±125 feet. When the altitude digitizer is installed in an aircraft for use as the
transponder’s source of mode “C” information the digitizer must be recalibrated for
correspondence to the aircraft’s primary flight altimeter, as required by FAR 91.217 and
91.411. Model SSD120-35C-RS232 is designed to be field calibrated to meet this
requirement, as per the procedure described in either §4.3, or §4.4.
The correspondence required for altitude digitizers is fully addressed in SAE Aerospace
Standard AS8003 §3.11. The correspondence described by the SAE standard requires
the digitizer to report altitude within ±125 feet of the primary flight altimeter’s reading
when the pressure datum is set to 29.92 In. Hg. (1013 MB) absolute. The SAE standard
also requires a transition accuracy of ±75 feet of the nominal transition point for that
altitude. A transition is defined as the point at which the digitizer changes from one
altitude to the next, either increasing or decreasing altitude. The nominal transition point
of the ICAO code occurs 50 feet prior to the altitude in question. See Figure 13.
There are two different methods used to adjust the calibration of the SSD120-35CRS232. The technician need only perform the method that is best suited for the
application in question. There is no need to perform both methods. The digitizer may be
adjusted using two potentiometers, which affect the span and reference of the pressure
transducer. This device may also be adjusted utilizing an externally addressable
EEPROM, which is configured to accept an alternate error curve entered to the digitizer
via Trans-Cal’s ECP-100 or alternatively, via an IBM compatible PC.
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The Span Adjust calibration (§4.3) is normally used in applications where only a slight
modification is required to bring the altitude digitizer curve up or down.
The Dynamic Calibration procedure (§4.4) is an alternate method used to match the
altitude digitizer to the primary flight altimeter or NIST standard. It assumes the digitizer
and altimeter are connected as shown in Figure 11. The technician may adjust the input
pressure to the digitizer and primary flight altimeter to the same pressure altitude and
then enter this altitude into the ECP-100 or an IBM compatible computer, which will
transmit the correction to the digitizer’s EEPROM.
This calibration procedure differs from the Span Adjust procedure in that the
adjustments are made at 1000-foot intervals and the Digitizer is adjusted at the 0 foot
mark NOT the ICAO data nominal transition point.
4.2 Required Equipment Span Adjust
(See span adjust block diagram.)
1. Primary Flight Altimeter.
2. +12 or 28VDC power supply.
3. A pitot-static test set, capable of exercising the altimeter and digitizer over a
range of –1000 feet to the maximum altitude of the digitizer.
4. A ramp checker or test set capable of interrogating the transponder. Optional:
ATS-400 or equal device which will allow the display of the 100 foot resolution
parallel altitude data.
4.3 Span Adjust Procedure
ALWAYS DETERMINE THE DESIGN LIMITS OF THE INSTRUMENTS
ATTACHED TO THE STATIC SYSTEM. LOCATE AND IDENTIFY ALL
INSTRUMENTS ATTACHED TO THE SYSTEM AND REFER TO THE
MANUFACTURER’S DATA FOR MAXIMUM RATE OF CLIMB OR DESCENT,
AND ANY SPECIAL TEST CONDITIONS WHICH MUST BE COMPLIED WITH
TO PREVENT DAMAGE.
CAUTION
1. Connect the pitot-static test equipment to the aircraft’s static line, and connect the
transponder test set per the manufacturer’s recommendations. The digitizer’s two
altitude adjustment potentiometers are identified as L and H, representing low and
high altitude. The HIGH adjustment is closest to the edge of the housing, and the
LOW adjustment is closer to the center of the housing.
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NOTE:
Changing either potentiometer will affect the other. An adjustment made to correct the low
transition point, will move the high transition point, and require an adjustment of the high
potentiometer.
Figure 10 Low & High Calibration Adjustments
2. Apply power to the altitude digitizer and transponder.
3. Set the primary flight altimeter barometric pressure to 29.92 In. Hg. (1013 MB).
4. Interrogate the transponder with the ramp tester, while observing the digitizer ICAO
altitude code, decrease pressure to the point where the altitude code just makes a
transition to the maximum altitude encoded. Verify that the digitizer is within ±125
feet of the primary flight altimeter’s reading. If not, adjust the high potentiometer until
the digitizer transition point is within ±30 feet of the nominal transition point. E.g.,
while ascending, the digitizer should transition from 29,900 feet to 30,000 feet at
29,950 feet nominally.
5. Increase pressure until the digitizer’s output just makes the transition from 100 feet to
0 feet. Verify that the altitude digitizer reports within ±125 feet of the primary flight
altimeter. If not, adjust the low potentiometer until the transition point is within ±30
feet of the nominal transition point. E.g. while descending, the digitizer should
transition from +100 to 0 feet at +50 feet nominally.
6. Repeat steps (4) and (5) until the ±125 foot tolerance is achieved for both the
maximum calibration altitude and the minimum calibration altitude.
7. Exercise the aircraft’s static system over the operating range of the altitude digitizer
and, with increasing and decreasing pressure, verify at a minimum of ten test points
that the altitude digitizer and primary flight altimeter correspond within the ±125 foot
tolerance. Lightly tap the altimeter before each reading to eliminate friction. If
correspondence is not achieved at any test point, the primary flight altimeter may
require calibration.
8. Verify that the digitizer’s output is disabled when the transponder is not in mode “C”,
or when the “Altitude Disable” switch is in the off position.
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Figure 11 Span Adjust Block Diagram
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4.4 Dynamic Calibration Adjustment Procedure using the ECP-100
Reference: FAR 91.217, FAA Advisory Circular 43-6C
FAR 91.411, FAR 43-Appendix E and F
FAA TSO-C88a, EASA ETSO-C88a, SAE AS8003
NOTE: To ensure correspondence with all on-board pressure altitude systems,
altitude digitizers that are not providing information to the ATC transponder
should be tested to ensure correspondence to the primary flight altimeter, as per
FAA AC43-6C.
This procedure will allow adjustment to the calibration curve of the SSD120-35C-RS232
or using the ECP-100 as an aide in matching the digitizer output to a primary flight
altimeter or NIST traceable pressure standard. This procedure differs significantly from
the Span Adjust Procedure described in §4.3. The Dynamic Calibration Procedure
makes adjustments to the altitude data stored in the digitizer’s EEPROM. The technician
may make adjustments to the digitizer error curve in 1000 foot increments, over the
entire operating range with the single exception of the negative 1000 foot mark. The
technician will make the adjustments at the 0 or whole altitude mark, NOT at the parallel
data’s nominal transition point. See Figure 13. The digitizer will automatically adjust the
ICAO parallel altitude data to transition 50 feet prior to the 0 mark. E.g., the digitizer’s
ICAO parallel altitude code will transition from 900 to 1000 feet while the serial altitude
data is transmitting 950 feet.
CAUTION!
ALWAYS DETERMINE THE DESIGN LIMITS OF THE INSTRUMENTS ATTACHED TO
THE STATIC SYSTEM. LOCATE AND IDENTIFY ALL INSTRUMENTS ATTACHED TO
THE SYSTEM AND REFER TO THE MANUFACTURER’S DATA FOR MAXIMUM RATE
OF CLIMB OR DESCENT, AND ANY SPECIAL TEST CONDITIONS WHICH MUST BE
1. Connect the digitizer, ECP-100, and NIST standard or flight altimeter as shown in
the Figure 13 and apply power.
2. Slide the ECP-100 CAL. PROGRAM selector to the leftmost PROGRAM
position.
3. Apply power to the altitude digitizer and slide the ECP-100 power switch to the
on position.
4. Set the altimeter barometric input to 29.92In.Hg. (1013MB). Adjust the static
system pressure and stabilize at the first altitude to be calibrated. The first
possible correction for Trans-Cal digitizers is at 0 feet. All adjustments to the
digitizer calibration curve occur at 1000-foot intervals. Use the ALTITUDE UP
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and ALTITUDE DOWN buttons to adjust the ECP-100 to the current pressure
altitude prior to pushing the INITIATE PROGRAM pushbutton.
5. Press the INITIATE PROGRAM pushbutton once. The ECP-100 will enter a
digital correction into the digitizer’s EEPROM at the current pressure altitude.
6. Adjust the input pressure to the next 1000-foot increment and adjust the ECP-
100 to the next 1000-foot increment and repeat step 5. Continue throughout the
operating range of the altitude digitizer and altimeter.
7. Exercise the aircraft’s static system over the operating range of the altitude
digitizer and, with increasing and decreasing pressure, verify at a minimum of ten
test points that the altitude digitizer and primary flight altimeter correspond within
the ±125 foot tolerance. Lightly tap the altimeter before each reading to eliminate
friction. If correspondence is not achieved at any test point, the altimeter may
require calibration.
8. Verify that the digitizer’s output is disabled when the transponder is not in mode
“C”, or when the “Altitude Disable” switch is in the off position.
NOTE: If an error is entered into the digitizer, adjust the pressure to the correct
altitude and re-enter the correction. To clear ALL corrections to the digitizer error
curve press the ALTITUDE UP PROGRAM pushbutton once. Then press and
hold the ALTITUDE DOWN pushbutton for two seconds. If the digitizer and flight
altimeter are within the ±125-foot requirement, then no further correction is
required. DO NOT adjust the digitizer’s high and low potentiometers during this
procedure.
Figure 12 Dynamic Calibration Set-Up
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4.5 Calibration Wiring Harness Using the ECP-100
4.6 Calibration Harness Using a PC with RS232 Input
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Figure 13 Digitizer Correspondence
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4.7 Serial Data Offset
When using serial data from the Altitude Digitizer for ADS-B or other navigational
instrument installations, verify that the 10’ resolution data is selected to prevent data
conflicts.
It is important to note that the
Serial RS232 data is offset from
the parallel grey code data by 50’.
The calibration requirement for
Altitude Digitizers requires the 100’
resolution grey code to transition
at the 50’ mark with a tolerance of
±125’.
Figure 14 displays the ideal case
for 11,000 feet.
The ideal Altitude Digitizer grey
code output will read 11,000’ when
the primary flight altimeter reads
from 10,950’ to 11,050’ with a
tolerance of ±125’.
The encoder’s 10-foot RS232 data
will output 11,000’ from 11,000’ to
11,010’ nominally.
The encoder’s 100-foot RS232
data will read 11,000’ from 11,000’
to 11,100’ nominally.
Figure 14 Serial Data Offset
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p
4.8 Serial Port Software Configuration Using the ECP-100
This procedure will allow the technician to assign separate serial data output
protocols to the altitude digitizer output ports. Connect the ECP-100 to the altitude
digitizer as shown in Figure 14.
Step 1: Remove power from the Altitude Digitizer, remove the four screws and cover
as shown in Figure 2. Slide the CAL. Program switch to its rightmost PROGRAM
position and connect the ECP-100 to the Altitude Digitizer as shown in Figure 14.
Step 2: With the ECP-100 power switch in the OFF position, apply power to the
Altitude Digitizer, then slide the ECP-100 power switch to the on position. The ECP-
100 will beep twice then display the current pressure altitude transmitted from the
altitude digitizer.
ALTITUDE PROGRAMMER
ALT 00800
Step 3: Push the READ SET-UP DATA pushbutton once. The ECP-100 will display
the current serial port protocol settings for 15 seconds, and then return to the altitude
programmer display page. The factory setting is pictured below.
100 Foot Resolution
TxD1= UPS 1200bps
TxD2= UPS 1200b
DATA = 000
s
Step 4: Slide the RESOLUTION selector switch to the desired serial altitude data
resolution 10’ or 100’.
Step 5: Rotate the TxD1 and TxD2 selector knobs to the desired output protocol. For
the purpose of this example we will set TxD1 to transmit the UPS protocol and TxD2
to transmit the Trimble/Garmin protocol.
Step 6: Press the INITIATE PROGRAM pushbutton once. The display will beep then
flash PROGRAMMING and display the protocols to be programmed. Wait until the
ECP-100 emits a long beep and displays OPERATION COMPLETED then returns to
the ALTITUDE PROGRAMMER display.
10 Foot Resolution
TxD1= UPS 1200bps
TxD2= Trimble/Garmin
PROGRAMMING
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Step 7: Confirm the port programming by pressing the READ SET-UP DATA
pushbutton. It should display the settings applied in the previous steps. In the case of
our example the display would appear as below.
10 Foot Resolution
TxD1= UPS 1200bps
TxD2= Trimble/Garmin
DATA=212
Step 8: Slide the ECP-100 power switch to the off position and remove power from
the Altitude Digitizer.
Step 9: Replace the cover and screws. The encoder is now programmed and ready
to operate.
Figure 15 Serial Port Configuration Using the ECP-100
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Section 5.0 Digitizer Interconnection Tables
The following digitizer interconnections are provided as a quick reference only, and though
they are correct to the best of our knowledge, always consult the latest installation,
operation, and service bulletins from the equipment manufacturer.
Table I Bendix King
Function
SSD120
15 Pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
8
15
Bendix/King
KT73 & KT 74
Pin Number
D4 8 *
Bendix/King
KT76/78
Pin Number
1
*
Bendix/King
KT76A/78A
Pin Number
1
V X
Bendix/King
KXP
Pin Number
Bendix/King
KXP 755
Pin Number
A1 M 6 M G A
A2 K 7 K H D
A4 J 9 J J k
B1 E 4 E K f
B2 C 1 C L g
B4 B 2 B M Y
C1 D 3 D P U
C2 L 8 L R T
C4 H 10 H S W
Output
Enable
+14 to
28Vdc
Input.
Ground
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s avionics
buss protected by
a fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s avionics
buss protected by
a fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s avionics
buss protected by
a fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
Connect to
aircraft ground.
Serial Data Connection for the Bendix/King KT 73 & KT 74 Transponder
SSD120-35C-RS232
DA-15P Connector
7 or 14
15
KT 73 - No shunts, software
select only.
KT 74 – Close shunt pins J4 and J6. Leave J5
open.
Connect serial OR parallel data not both! The KT 73 & KT 74 will default to the 100’ resolution parallel code, if both data
formats are connected.
1
Data for this connection is not available at this time.
Function
KT 73
24 Pin Conn.
TxD to RxD 7 3
Ground 1 or A 1
KT-73 Only Software select
UPSAT 618
Protocol.
KT 74
J2 Conn.
KT 74 Close
shunt J4 and
J6.
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Table II Cessna, Narco, Microair
Cessna
SSD120
15 Pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
Function
D4 10 *
A1 14 7 2 9
A2 13 6 4 10
A4 15 8 8 11
B1 19 12 9 12
B2 17 10 10 13
B4 16 9 11 17
C1 21 14 1 18
C2 18 11 3 19
C4 20 13 5 20
Output
Enable 11 5 12
RT359A,
RT459A,
RT859A
Pin Number
Narco AT-150
AT-50, AT-50A
Pin Number
2
*
Narco AT-6A
AT-5, AT-6
Pin Number
2
21
Microair
T2000
Connect to
aircraft ground.
+14 to
28Vdc
8
Input 9 18 13 2
Connect to
15
Ground
aircraft
ground.
Connect to aircraft
ground. 14
Connect to
aircraft ground.
Narco AT-50 and AT-50A Installations
The Narco AT-5A, AT-6A, AT-50 and AT-50A transponder will not accept parallel data from
the SSD120-35C-RS232 Altitude Digitizer. A modification to remove the output decoupling
capacitors is required and the unit may be ordered from the factory with this modification.
Order Model Number SSD120-35C-RS232 with Mod 1.
NOTE: The Narco AT-50 and earlier transponder models require a modification before
they will function correctly with any Altitude Digitizer. This modification is outlined in
Narco Service Bulletin AT-50A-5.
2
Data for this connection is not available at this time.
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Table III Garmin
SSD120
15 Pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
8
15
Function
Garmin
GTX 320 & 327
Pin Number
Garmin
GTX 330 &
330D
Pin Number
This column left
blank
intentionally.
This column left
blank
intentionally.
D4 18 11
A1 3 2
A2 5 4
A4 6 5
B1 9 7
B2 11 9
B4 12 10
C1 10 8
C2 4 3
C4 7 6
Output
Enable
13 or 25 or
aircraft ground 50
Pin 62 through
14 to
28Vdc
Input
Ground
14 to 28Vdc
Input
Connect to
aircraft ground.
a 3 amp 50V
reverse rated
diode.
Connect to
aircraft ground.
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Table IV Garmin
Serial Data Connection for the Garmin GTX327 Transponder
JP1 Header:
JP1 Header:
SSD120-35C-RS232
DA-15P Connector
Function
GTX327
25 Pin Connector
14 or 7 TxD to RxD 19
15 Data Ground 13 or 25
Open shunt J5
Close shunt J6
Table V Garmin
Serial Data Connection for the Garmin GTX330 and 330D Transponder
SSD120-35C-RS232
DA-15P Connector
14 or 7 TxD to RxD 24 (RS232 In 2)
15 Data Ground Data Ground
Open shunt J5
Close shunt J6
Function
GTX330
62 Pin Connector
To allow the Garmin GTX 327, 330 and 330D transponders to communicate with the
SSD120-35C-RS232 go to the Setup Page and set the Altitude Source (ALT SRC) to
receive data in the Icarus RS232 format.
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Table IVI Edo-Air, Genave, Collins, Radair
Function
SSD120
15 Pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
8
15
Edo-Air
RT-777
Pin Number
Genave
Beta 5000
Pin Number
Collins
TDR 950
Pin Number
Radair
250
Pin Number
D4 15 0 3 15
A1 7 4 12 7
A2 5 5 10 6
A4 3 6 7 13
B1 12 7 6 9
B2 13 8 5 10
B4 14 9 4 11
C1 8 10 8 14
C2 6 11 11 16
C4 4 12 9 12
Output
Enable 2 3
Connect to
aircraft ground. 19
Connect to
Connect to
aircraft’s avionics
14 to
28Vdc
Input
buss protected
by a fuse or
circuit breaker. 2
Ground 2
Connect to
aircraft ground.
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker. 22
Connect to
aircraft ground.
Connect to
aircraft ground.
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Table VII Bendix, Wilcox, UPS AT
Function
SSD120
15 pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
8
15
Bendix
TPR-2060
Pin Number
D4 *
3
N C 35
Bendix
TR641A/B
Pin Number
Wilcox
1014A
Pin Number
UPS AT
Apollo SL70
Pin Number
A1 4 A k 13
A2 6 B c 31
A4 8 C W 12
B1 9 D T 33
B2 10 E L 14
B4 11 F D 32
C1 3 H P 16
C2 5 J f 34
C4 7 K Z 15
Output
Enable
14 to
28Vdc
Input
Ground Connect to
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
Connect to
aircraft ground.
Connect to
aircraft ground.
Connect to
aircraft’s
avionics buss
protected by a
fuse or circuit
breaker.
Connect to
aircraft ground.
Table VIII UPS AT
Serial Altitude Data Connection for the Apollo SL70 Transponder
SSD120-35C-RS232
DA-15P Connector
14 or 7
15
Function UPS AT SL70
TxD to RxD 4
Ground 3
To allow the UPS AT SL70 transponder to accept serial data from the SSD120-35C-RS232
go to the Test Mode on the SL70 Conf page and set the Altitude Source (ASrc) to
receive Serial (Ser) data. On the BAUD page select 1200.
3
Data for this connection is not available at this time.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table IX Becker, Terra
Function
SSD120
15 pin
Conn.
Becker
Avionic Systems
ATC3401
ATC2000
Becker
Avionic
Systems
ATC4401
Terra
TRT-250
TRT-250D
This column
left blank
intentionally.
1
2
3
4
5
9
10
11
13
12
D4 23 20 9
A1 16 1 5
A2 15 2 17
A4 14 3 16
B1 17 14 15
B2 19 15 2
B4 18 16 14
C1 22 17 3
C2 21 18 4
C4 20 19 18
Output
6
Enable 24 25 12
+14 to
8
28Vdc 6 6 20
Connect to
15
Ground 24 25
aircraft ground
Table X Trig, Avidyne
Serial Altitude Data Connection for the Trig TT31 and Avidyne AXP340
Mode S Transponder
SSD120-35C-RS232 Function
14 or 7
15
JP1 Header:
Close shunt J4
Open shunt J5
Close shunt J6
NOTE: The TT31 and the AXP340 will accept either parallel or serial altitude data inputs in either the Trimble/Garmin or the
Shadin “RMS” data formats. The TT31 will select the parallel data inputs if both are connected. Serial data inputs are
recommended for better Mode S data resolution. Ground J4 to select 10-foot resolution.
TxD to RxD 7
Ground A or 1
Trig TT31
Avidyne AXP340
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Table XI Bendix King EGPWS
SSD120
15 pin
Conn.
1
2
3
4
5
9
10
11
13
12
6
8
15
Function
Bendix/King
560EGPWS
&
MK-XXI EGPWS
Bendix/King
KMH 870
IHAS
Processor
This column
left blank
intentionally
.
D4 No connection 18
A1 12 11
A2 52 10
A4 33 9
B1 14 14
B2 34 13
B4 73 12
C1 32 17
C2 13 16
C4 72 15
Output
Enable
+14 to
28Vdc
Ground
Connect to aircraft
ground
Connect to
avionics buss
protected by a
fuse or circuit
breaker
Connect to aircraft
ground
Connect to
aircraft ground
Connect to
avionics buss
protected by a
fuse or circuit
breaker
Connect to
aircraft ground
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table XII NavWorx ADS600-B
Serial Altitude Data Connection for the ADS600-B UAT Data Link Transceiver
SSD120-35C-RS232
DA-15P
14 or 7
JP1 Header:
Close shunt J4
Open shunt J5
Close shunt J6
15
Function
TxD to RxD 3
Ground 4
ADS600-B
Connector P1
Table XIII NavWorx ADS600-EXP
Serial Altitude Data Connection for the ADS600-EXP UAT Data Link Transceiver
SSD120-35C-RS232
DA-15P
14 or 7
JP1 Header:
Close shunt J4
Open shunt J5
Close shunt J6
15
Function
TxD to RxD 3
Ground 4
ADS600-EXP
Connector P1
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Table XIV Connector Pin Assignments SSD120-35C-RS232
SSD120-35C-RS232
DA-15 Connector Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Strobe/ Output Enable
+14 to 28Vdc Input
D4
A1
A2
A4
B1
TxD2
B2
B4
C1
C4
C2
TxD1
Ground
Figure 16 DA-15P D-Subminiature Connector Front View
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table XV Quick Guide to Common Serial Data Interconnects
For ALL applications, closing J4 enables 10’ data resolution.
Device Baud Rate/Data
Bits/Stop Bits/Parity
ARNAV (data in meters)
9600/8/1/None Software Set-up Only
5000 MFD 505/506/512
DR-100 Wx Link
Bendix/King KT 73
Bendix/King KT 74
Garmin 400 & 500 Series GPS
1200/7/1/Odd Software Set-up Only
9600/8/1/None J4 Closed
9600/8/1/None J4 Closed
GNC300, GTX327, GTX330
NavWorx ADS600-B &
9600/8/1/None J4 Closed
ADS600-EXP
Trig TT31
Trimble 2101
UPS AT GX50, GX60, GX65
1200/8/1/None None
9600/8/1/None J5 Open
1200/8/1/None J5 Open
MX20, SL70
UPS AT 618 Loran
1200/7/1/Odd Software Set-up Only
TCI SSD120-35C-RS232
JP1 Header Shunt
Position.
J5 Open
J6 Closed
J5 Open
J6 Closed
J5 Open
J6 Closed
J6 Closed
J6 Open
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Section 6.0 GPS/MFD & Miscellaneous Connection Data
Given the speed with which new GPS and MFD units are entering the market, it is impossible to
provide data on every device. The following digitizer/GPS interconnections are provided as a quick
reference only, and though they are correct to the best of our knowledge, always consult the latest
installation, operation, and service bulletins from the GPS or MFD manufacturer.
Table XVI Apollo GX Series
Apollo Model GX50, GX60, GX65
Apollo GX50, GX60,
GX65
Signal
RxD2
Ground
Apollo
37 Pin D-Sub
Connector
SSD120-35C-RS232
DA-15P Pin Connector
21 14 or 7
20 15
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Open shunt J6
Apollo GX50, GX60, GX65 Software Configuration
In test mode, rotate the Large knob to select serial port configuration RX.
Press SEL, rotate the large knob to select the RxD2 port, rotate the small knob to select
AltEnc input.
Table XVII Apollo MX20
Apollo Model MX20 Multi-Function Display
Apollo
Apollo MX20
Signal
37 Pin D-Sub
Connector
SSD120-35C-RS232
DA-15P Pin Connector
RxD2
Ground
21 14 or 7
3 15
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Open shunt J6
Apollo MX20 Software Configuration
Under External Data Source set altitude source to Port 2.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table XVIII Trimble
Trimble 2101 Approach
Trimble Signal Trimble 2101
Port 1
RxD+
RxD-
Ground
7 24 15
8 36 14 or 7
3 or 20 3 or 20 15
Trimble 2101
Port 2
SSD120-35C-RS232
DA-15P Pin Connector
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Close shunt J6
Trimble Approach Plus GPS Receiver Software Configuration – Installation Setup
Access the 2101 installation setup menu and go to the SERIAL I/O SETUP. Select the GPS
serial port which is to receive the pressure altitude data,
SERIAL-1 IN or SERIAL-2 IN.
Set data format to ENCODER.
Table XIX Trimble
2101 I/O Approach Plus GPS Receiver
Trimble Signal Trimble 2101
Port 1
Trimble 2101
Port 2
SSD120-35C-RS232
DA-15P Pin Connector
RxD+
RxD-
Ground
J1-7 J1-24 15
J1-8 J1-36 14 or 7
J1-3 or 20 J1-3 or 20 15
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Close shunt J6
2101 I/O Approach Plus GPS Receiver Software Configuration – Installation Setup
Access the 2101 installation setup submenu and go to the SERIAL I/O SETUP. Select the
GPS serial port, which is to receive the pressure altitude data, SERIAL-1 IN or SERIAL-2
IN. Set data format to ENCODER.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Table XX Garmin
Garmin 400 and 500 Series GPS Devices (Includes 430W and 530W)
Garmin
78 Pin Conn.
(P4001)
SSD120-35C-RS232
DA-15P Pin Connector
57
77 or 78
14 or 7
15
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Close shunt J6
Garmin 400 series GPS software configuration
To allow the Garmin 400 series GPS to communicate with the SSD120-35C-RS232 go to the Main
RS232 Config page and set channel 1 input to Icarus-alt.
Table XXI Garmin
Garmin GNC 300 GPS/Comm
GNC 300
37 Pin Connector
J101
Function
SSD120-35C-RS232
DA-15P Pin Connector
17 RxD to TxD 14 or 7
26 or 22 Data Ground 15
JP1 Header:
Close shunt J4 for 10’ resolution
Open shunt J5
Close shunt J6
To allow the Garmin 300 series GPS/Comm to communicate with the SSD120-35C-RS232 go to the
I/O Test Page and set channel 1 input to Icarus-alt.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Table XXII ARNAV
ARNAV Systems 5000 Series Multi-Function Display
ARNAV
5000
25 Pin Connector
SSD120-35C-RS232
DA-15P Pin Connector
15
13 or 25
Protocol, Software select
ARNAV protocol see §4.8.
14 or 7
15
Table XIII ARNAV
ARNAV Systems GPS-505/506/512 GPS Sensor
ARNAV
GPS-505/506/512
DB-25 Connector
8
9
SSD120-35C-RS232
DA-15P Pin Connector
14 or 7
15
Protocol, Software select
ARNAV protocol see §4.8.
Table XIV ARNAV
ARNAV Systems DR-100 WxLink Receiver/ Multiplexer
ARNAV
DR-100
25 Pin Connector
10
13 or 25
SSD120-35C-RS232 Software Configuration Note for Use with ARNAV Devices
The SSD120-35C-RS232 must be software configured per §4.8 to operate with ARNAV system
devices.
SSD120-35C-RS232
DA-15P Pin Connector
14 or 7
15
Protocol, Software select
ARNAV protocol see §4.8.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Table XXV Century Flight Systems
Digital Altitude Preselect/Alerter
1D960 ICAO Parallel Input
Digital Altitude Preselect/Alerter
1D960 Serial Data Input
SSD120
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Function 1D960 Pin
D4 9
A1 25
A2 40
A4 10
B1 26
STROBE Connect to
Ground
TxD2 --
+Vdc Input --
B2 22
B4 7
C1 23
C4 8
C2 38
TxD1 --
GROUND --
SSD120
Pin
14 or 7
Function 1D960
Pin
TxD to RxD 37
Please Note: The Century 1D960 manual lists an RS232 serial altitude data input on pin 37 with a
data common on pin J1-46. At the time of this printing, Trans-Cal has not tested the 1D960 input for
compatibility.
881625 Rev. A
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Section 7.0 Instructions for Continued Airworthiness
The SSD120-35C-RS232 is an all solid-state device and requires no specific periodic
maintenance to maintain its airworthiness, and there are no user serviceable parts. The
Altitude Digitizer is to be tested on a biennial basis after initial installation by a qualified
avionics facility. The testing carried out during the transponder and pitot-static system tests
as required by current Federal Aviation Regulations are considered sufficient to validate
proper operation of the Altitude Digitizer. If the Altitude Digitizer reports an error in excess of
±125 feet compared to the primary flight altimeter, then recalibration as per §4.0 of this
manual is required. If the error cannot be corrected through this procedure, then the unit is
to be repaired or replaced. Contact Trans-Cal Industries for further information.
Section 8.0 Adapter Plate Ordering Information
The adapter plates listed below will allow the use of competing digitizer manufacturers and
older Trans-Cal quick release mounting trays with the SSD120-35C-RS232. These adapter
plates are designed to allow quick replacement of Altitude Digitizers. Use the following
Trans-Cal part numbers to order adapter plates.
Manufacturer Model TCI Adapter Plate Part Number
ACK Model A-30 103059
Ameri-King Model AK350 Series 103061
Narco Model AR-850 No adapter required.
Shadin Model 8800-X Series 103060
Sandia Model SAE5-35 103035
Trans-Cal Model D120-P2-T Not available.
Trans-Cal Model SSD120-(XX)A 103038
Pictured below is the SSD120-35C-RS232 mounted on adapter plates and quick release
mounting trays for various devices. Quick release mounting trays are NOT included with the
adapter plates.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
=
×
Section 9.0 Frequently Asked Questions
1. How often must the Altitude Digitizer be calibrated; is there periodic maintenance
required?
There is no periodic maintenance required. The Digitizer is tested and calibrated, if
required, during the aircraft’s biennial certification of the transponder and static
system.
2. How many devices may be driven off of the parallel ICAO Altitude data port?
The number of devices that may be connected to the Digitizer ICAO altitude output is
a function of the power required. The Digitizer parallel data outputs are
“uncommitted” collectors of a transistor array which are “pulled-up” through a
resistive load by the transponder (or other device) to some positive voltage. This
voltage may range from about +3 to +40Vdc. Each Digitizer data output line (i.e. D4,
A1, A2, A4 etc.) is capable of providing 35 mA (0.035 Amperes) with a not to exceed
power rating of 100mW (0.1 Watts), when it is “sinking” current in the “on” position.
Typical modern applications require about 1 milliampere or less per data line, per
device.
In the circuit illustrated below, the current is calculated as 0.9mA at 8.1mW. At this
current and power rating, a total of 12 identical devices could be connected to the
digitizer. Given the wide variety of input circuits capable of interfacing with the
Digitizer and the possibility of crosstalk, careful planning of the electrical loads acting
upon the Digitizer output is advised.
V
R
I
=
9
Vdc
AmpsOhms
0009.010000
=
PIV =)(
TYPICAL TRANSPONDER PARALLEL
DATA INPUT CIRCUIT 1 OF 10
WattsAmpsVdc 0081.00009.09
D4 THRU C4
DIGITIZER PARALLEL DATA OUTPUT
CIRCUIT 1 OF 10
LOGIC
D4 THRU C4
BASE
COLLECTOR
EMITTER
PIN 6
STROBE/OUTPUT
ENABLE
+9Vdc
10K
LOGIC
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
3. Why do altitude encoding errors occur when connecting a second or third device
to the Altitude Digitizer, but not when only one device is connected?
This is a symptom of “Cross-Talk.” This condition typically occurs when the
devices connected to the Altitude Digitizer are “pulling-up” to different
voltages without diode isolation. When the Altitude Digitizer is in the “off”
state the data line electrical current may flow in undesired directions due to
this pull-up voltage imbalance. Most modern avionics devices are diode
isolated; but in applications where older equipment is mixed with new
devices, blocking diodes may be required to isolate the older device.
Germanium or Schottky blocking diodes are the preferred devices to install
due to the low forward voltage drop across the diode. Connect as detailed in
the illustration below. Use of general purpose silicon diodes are NOT
recommended, as the larger voltage drop may interfere with the logic
threshold detection in the equipment.
TYPICAL TRANSPONDER PARALLEL
DATA INPUT CIRCUIT 1 OF 10
D4 THRU C4
+5Vdc
4.7K
DIGITIZER PARALLEL DATA OUTPUT
CIRCUIT 1 OF 10
D4 THRU C4
LOGIC
BASE
TYPICAL BLOCKING
DIODE 1 OF 10
D4 THRU C4
COLLECTOR
EMITTER
TYPICAL ICAO PARALLEL DATA
INPUT CIRCUIT 1 OF 10
+9Vdc
10K
LOGIC
D4 THRU C4
LOGIC
PIN 6
STROBE/OUTPUT
ENABLE
4. My transponder does not have a D2 or D4 input. What do I do with these signals
from the Digitizer?
Leave unused data bits unconnected or connect to circuit ground.
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
5. What is the Strobe or Signal Common or Output Enable function on the ICAO
altitude data port?
This is a control signal for the ICAO parallel altitude data. On devices
manufactured by Trans-Cal this function is always on pin 6 of the ICAO
altitude port. A “high” or “open” on this pin will disable the ICAO altitude data.
A “low” or “ground” on this line will enable the altitude data. Some
interconnecting devices may use this signal to control the flow of data from
the Digitizer. Be aware that when using this signal and connecting multiple
devices to the Digitizer, interruptions of the ICAO data will occur when the
controlling device “strobes” the Digitizer.
Section 10.0 Known Compatibility Issues
10.1 Narco Older Transponders and the SSD120-35C-RS232
The Narco AT-5A, AT-6A, AT-50 or AT-50A transponder will not accept data from the
SSD120-35C-RS232 Altitude Digitizer. Order Model Number SSD120-35N-RS232
with Mod. 1. Please note! This modification may NOT be performed in the field.
Please also note! The Narco AT-50 and earlier transponder models require a
modification before they will function correctly with any Altitude Digitizer. This
modification is outlined in Narco Service Bulletin AT-50A-5.
10.2 King KT-75
The King KT-75/75R uses the old RTL (resistor transistor logic) pulling up to about 3
volts; consequently the open collectors of the SSD120-35C-RS232 will not pull the
signal past the KT-75 logic threshold.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
10.3 S-Tec (Collins) TDR-950
The TDR950 must be powered-up first,
or the SSD120-35C-RS232 must be
diode isolated to prevent the TDR 950
from invalidating the digitizer data.
All diodes 1N4454 (CPN 353-3741-010).
10.4 Trans-Cal SSD120-35C-RS232 Backwards Compatibility
All Model SSD120-35C-RS232 are pin-for-pin replacements for all D120-P2-T and
Model SSD120-(XX), with ONE exception. The older SSD120-(XX) utilized a 28V
heater ground on pin 1 of the D-Subminiature connector. Pin 1 is the D4 data bit on
the SSD120-35C-RS232 models. Rewire the harness appropriately, if D4 is an active
bit. No action is required if D4 is unused. All Model SSD120-35C-RS232 are pin-forpin replacements for all Model SSD120-(XX)A.
Model Compatibility with SSD120-35C-RS232
D120-P2-T Rewire +Vdc to Pin 8
SSD120-(XX) Rewire +Vdc to Pin 8
SSD120-(XX)A Rewire +Vdc to Pin 8
SSD120-(XX)N Rewire +Vdc to Pin 8
10.5 SSD120-35C-RS232 Compatibility to Competitor’s Products
Manufacturer Compatibility with Model SSD120-35C-RS232
ACK Technologies Model A-30.9 Pin-for-pin compatible.
Ameri-King Corp. Model AK-350 Pin-for-pin compatible.
Becker Avionic Systems Model BE6400-01-(XX) Utilizes an RS422 interface
and in NOT compatible with Trans-Cal Encoders
Narco Model AR-850 Rewire +Vdc on Pin 8
Narco Model AR-500 Uses a 25 Pin D-Sub connector and
must be rewired to use SSD120-35C-RS232.
Rocky Mountain
Instrument
Model μEncoder no display function and requires
rewiring the harness to use SSD120-35C-RS232.
Shadin See chart below.
Sandia Model SAE5-35 ICAO data is pin-for-pin compatible.
Rewire +Vdc on Pin 8
Terra Model AT3000 Rewire +Vdc on Pin 8
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Manufacturer Compatibility with Model SSD120-35C-RS232
Shadin Model 8800M ICAO data is pin-for-pin compatible, Requires rewire to
use +Vdc on pin 8, serial data on pins 7 and or 14
Configure for UPS AT serial data message.
Shadin Model 8800G ICAO data is pin-for-pin compatible, RS232 data is
output on pin 14 and 7. Requires use of TCI model
SSD120-35C-RS232 and rewire to use +Vdc on pin 8.
Configure for Magellan serial data message.
Shadin Model 8800T ICAO data is pin-for-pin compatible, RS232 data is
output on pin 14 and 7. Requires use of TCI model
SSD120-35C-RS232 and rewire to use +Vdc on pin 8.
Configure for Trimble serial data message.
Shadin Model 8800A ICAO data is pin-for-pin compatible, RS232 data is
output on pin 14 and 7. Requires use of TCI model
SSD120-35C-RS232 and rewire to use +Vdc on pin 8.
Configure for ARNAV serial data message.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Outline Drawing
881625 Rev. A
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Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Environmental Qualification Form
Nomenclature: Altitude Digitizer
Model No.: SSD120-35C-RS232 FAA TSO-C88a and EASA ETSO-C88a
Manufacturer: Trans-Cal Industries, Inc., 16141 Cohasset St. Van Nuys, CA 91406
DO-160E Tested: October 2007
Conditions Section Description of Tests Conducted
Temp. and Altitude
Low Temperature
High Temperature
In-Flight Loss of Cooling
Altitude
Decompression
Overpressure
Temp. Variation §5.0 Tested to Category B.
Humidity §6.0 Tested to Category A.
Operational Shock and Crash
Safety
Vibration §8.0 Tested to Category S Fixed Wing Zone 1, 2, 3 & 5 Curve M and
Explosive Atmosphere §9.0 Identified as Category X, no test performed.
Waterproofness §10.0 Identified as Category X, no test performed.
Fluids Susceptibility §11.0 Identified as Category X, no test performed.
Sand and Dust §12.0 Identified as Category X, no test performed.
Fungus Resistance §13.0 Identified as Category X, no test performed.
Salt Spray §14.0 Identified as Category X, no test performed.
Magnetic Effect §15.0 Tested to Category Z.
Power Input §16.0 Tested to Category B.
Voltage Spike §17.0 Tested to Category B.
Audio Frequency Conducted
Susceptibility – Power Inputs
Induced Signal Susceptibility §19.0 Tested to Category BC.
RF Susceptibility (Radiated and
Conducted)
Emission of RF §21.0 Tested to Category B.
Lightning Induced Transient
Susceptibility
Lightning Direct Effects §23.0 Identified as Category X, no test performed.
Icing §24.0 Identified as Category X, no test performed.
Electrostatic Discharge §25.0 Tested to Category A.
Fire, Flammability §26.0 Identified as Category X, no test performed.
Remarks:
During power input tests, the device was subjected to subparagraph 16.6.1.4b, requirement
for devices with digital circuits.
§4.0
§4.5.1
§4.5.2 & 4.5.3
§4.5.4
§4.6.1
§4.6.2
§4.6.3
§7.0 Tested to Category B.
§18.0 Tested to Category B.
§20.0 Tested to Category T for Radiated Susceptibility, and Category T
§22.0 Identified as Category X, no test performed.
Tested to Category D1.
No cooling required.
Tested to Category U Helicopter Zone 1 & 2 Curve F & F1.
for Conducted Susceptibility.
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Owner/Installation Manual Model SSD120-35C-RS232 Trans-Cal Industries, Inc.
Part Number Builder
881625 Rev. A
Page 55
28 June 2016
Trans-Cal Industries, Inc. Owner/Installation Manual Model SSD120-35C-RS232
Manufacturer Direct Warranty
Do Not Return to Place of Purchase
Trans-Cal Industries warrants each Model SSD120-35C-RS232 solid state altitude digitizer to be free of defects in
workmanship and materials for a period of 42 months after the original date of purchase from an authorized dealer, not to
exceed 60 months from the date of manufacture. Do NOT send this unit to a distributor or retailer for repair. Contact the
factory directly if you experience problems (818) 787-1221.
This warranty applies to the original purchaser of the instrument and is NOT transferrable. Trans-Cal’s obligation under this
warranty is limited to repairing or replacing any unit returned to Trans-Cal during the life of this warranty provided:
(1) The defective unit is returned to Trans-Cal, transportation pre-paid.
(2) Prior approval is obtained from Trans-Cal.
(3) The unit has not been damaged by misuse, neglect, improper operation, accident, alteration or improper installation.
(4) The unit is returned with a copy of the purchase receipt from the authorized dealer. (Online auction sites are not
Trans-Cal DOES NOT reimburse labor or shipping costs on warranty repairs. Trans-Cal Industries will be the sole judge as to
the cause of the malfunction and wherein the responsibility lies. No other obligation or liability is expressed or implied.
For the above warranty to become effective, the attached registration card must be completed and returned to Trans-Cal
Industries, properly filled out and signed by the dealer selling or installing this equipment.
Mail to: Trans-Cal Ind., Inc., 16141 Cohasset St., Van Nuys, CA 91406
authorized dealers.)
- - - - - - - - - - - - - - - - - - - - - - - - - - - cut here - - - - - - - - - - - - - - - - - - - - - - - - - -
MODEL: SSD120-35C-RS232 SERIAL NO: SRC-___________________
AIRCRAFT:______________________ NUMBER:__________________________
OWNER:___________________________________________________________
ADDRESS:_________________________________________________________
CITY:_________________________________ STATE:_______ZIP:___________
DEALER:__________________________________________________________
INSTALLED BY:____________________________________________________
LICENSE NO:______________________________________________________
INSTALLATION DATE:_______________________________________________
I hereby certify the above instrument was installed in accordance with 14 CFR, industry standards
and the instructions of Trans-Cal Industries. I further certify the instrument was functioning properly
on the date noted below.
SIGNED:___________________________________________________________
PRINT NAME:_______________________________________________________
DATE:______________________________________________________________
881625 Rev. A
Page 56
28 June 2016
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