Maintenance Manual
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GAD 42 MAINTENANCE MANUAL GARMIN International, Inc. 1200 E. 151st Street Olathe, KS 66062 USA 190-00159-01, Revision A July 2001
GAD 42 MAINTENANCE MANUAL GARMIN International, Inc. 1200 E. 151st Street Olathe, KS 66062 USA 190-00159-01, Revision A July 2001
Maintenance Manual
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... or printed copy of this manual or revision must contain the complete text of this copyright notice and provided further that any unauthorized commercial distribution of GARMIN Corporation. GARMIN International, Inc. 1200 E. 151st...GARMIN Corporation All Rights Reserved Except as expressly provided below, no part of this manual or any purpose without the express prior written consent of this manual may be reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium, for any revision hereto is strictly prohibited. Insertion Date By GAD 42 MAINTENANCE MANUAL...
... or printed copy of this manual or revision must contain the complete text of this copyright notice and provided further that any unauthorized commercial distribution of GARMIN Corporation. GARMIN International, Inc. 1200 E. 151st...GARMIN Corporation All Rights Reserved Except as expressly provided below, no part of this manual or any purpose without the express prior written consent of this manual may be reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium, for any revision hereto is strictly prohibited. Insertion Date By GAD 42 MAINTENANCE MANUAL...
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... CFR, Chapter VII, Subchapter C) and which may be exported, released, or disclosed to $1,000,000 under Section 2410 of the Export Administration Act of 1979. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 2 Rev. A A violation of the EAR may not be subject to a penalty of up to 10 years imprisonment and a fine of...
... CFR, Chapter VII, Subchapter C) and which may be exported, released, or disclosed to $1,000,000 under Section 2410 of the Export Administration Act of 1979. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 2 Rev. A A violation of the EAR may not be subject to a penalty of up to 10 years imprisonment and a fine of...
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TABLE OF CONTENTS Paragraph Page 1.0 INTRODUCTION ...4 2.0 REPAIR ...4 3.0 TECHNICAL SPECIFICATIONS 4 4.0 GAD 42 INSTALLATION 4 5.0 GENERAL DESCRIPTION 4 5.1 Analog PC Board 4 5.2 CPU PC Board 5 6.0 BLOCK DIAGRAM 5 7.0 BASIC THEORY OF OPERATION 5 7.1 Power Supplies 5 7.1.1 Power Input Circuitry 5 7.1.2 Main Power Supply 5 7.1.3 Power Supply (+5 V... 10 7.18 King Serial Transmitters 10 7.19 Discrete Inputs 10 7.20 Valid High Inputs 11 7.21 Control Outputs 11 8.0 ASSEMBLY DRAWING 11 1.0 INTRODUCTION GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 3 Rev. A
TABLE OF CONTENTS Paragraph Page 1.0 INTRODUCTION ...4 2.0 REPAIR ...4 3.0 TECHNICAL SPECIFICATIONS 4 4.0 GAD 42 INSTALLATION 4 5.0 GENERAL DESCRIPTION 4 5.1 Analog PC Board 4 5.2 CPU PC Board 5 6.0 BLOCK DIAGRAM 5 7.0 BASIC THEORY OF OPERATION 5 7.1 Power Supplies 5 7.1.1 Power Input Circuitry 5 7.1.2 Main Power Supply 5 7.1.3 Power Supply (+5 V... 10 7.18 King Serial Transmitters 10 7.19 Discrete Inputs 10 7.20 Valid High Inputs 11 7.21 Control Outputs 11 8.0 ASSEMBLY DRAWING 11 1.0 INTRODUCTION GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 3 Rev. A
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... as 429 data • Input analog true airspeed to the CPU PC board. Return faulty units to GARMIN for service. 3.0 TECHNICAL SPECIFICATIONS Technical specifications for the GAD 42 are listed in the GAD 42 Installation Manual, P/N 190-00159-00. 4.0 GAD 42 INSTALLATION Installation information for the unit is a microprocessor based input/output (I /O circuitry. Three 18-pin header board...
... as 429 data • Input analog true airspeed to the CPU PC board. Return faulty units to GARMIN for service. 3.0 TECHNICAL SPECIFICATIONS Technical specifications for the GAD 42 are listed in the GAD 42 Installation Manual, P/N 190-00159-00. 4.0 GAD 42 INSTALLATION Installation information for the unit is a microprocessor based input/output (I /O circuitry. Three 18-pin header board...
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...and the parallel combination of operation. 7.0 BASIC THEORY OF OPERATION 7.1 Power Supplies 7.1.1 Power Input Circuitry DC aircraft power input to the GAD 42 is a low pass filter formed by an integrated current-mode controller and switch operating at a fixed frequency of 100 kHz and producing ...the following output voltages: • +20 V • +12 V • -12 V • -20 V • +34 V GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 5 Rev. This same inductor forms an output low pass filter with ceramic capacitors on the input side to prevent high frequencies...
...and the parallel combination of operation. 7.0 BASIC THEORY OF OPERATION 7.1 Power Supplies 7.1.1 Power Input Circuitry DC aircraft power input to the GAD 42 is a low pass filter formed by an integrated current-mode controller and switch operating at a fixed frequency of 100 kHz and producing ...the following output voltages: • +20 V • +12 V • -12 V • -20 V • +34 V GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 5 Rev. This same inductor forms an output low pass filter with ceramic capacitors on the input side to prevent high frequencies...
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...backup storage capacitor voltage supply. 7.1.4 Power Supply (-5 V) The -5 V power supply provides bias voltage for the CMOS analog switches in the GAD 42. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 6 Rev. A These filters serve to charge backup storage capacitors. If the power input voltage drops below approximately ...over -voltage. Frequency compensation for the main power supply control loop maintains loop stability under all XYZ synchro inputs (shown in the GAD 42. The snubber operation is the soft start circuit. All Z synchro inputs are present on the +12 V and -12 V ...
...backup storage capacitor voltage supply. 7.1.4 Power Supply (-5 V) The -5 V power supply provides bias voltage for the CMOS analog switches in the GAD 42. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 6 Rev. A These filters serve to charge backup storage capacitors. If the power input voltage drops below approximately ...over -voltage. Frequency compensation for the main power supply control loop maintains loop stability under all XYZ synchro inputs (shown in the GAD 42. The snubber operation is the soft start circuit. All Z synchro inputs are present on the +12 V and -12 V ...
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... Board where they are read by an RC circuit. The output of the synchronous rectifier is a 400 Hz square wave delayed by an op amp. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 7 Rev. The output of this circuit is applied to the control input of the buffer is determined by a filter/attenuator...
... Board where they are read by an RC circuit. The output of the synchronous rectifier is a 400 Hz square wave delayed by an op amp. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 7 Rev. The output of this circuit is applied to the control input of the buffer is determined by a filter/attenuator...
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...signal. This element is a 10-channel, 8 bit, serial interface converter. All Z synchro outputs are grounded in the GAD 42. The SELECTED CRS DRIVE X/COS and SELECTED CRS DRIVE Y/SIN outputs have an additional circuit element not present on other ...by this device for the same purpose. This is set by this device reads all DC voltage monitoring in the GAD 42. 7.10 Digital-to the Analog PC board where they are protected from -1 (inverted) through 0 to +1 ...It is used for all internal DC voltages for validity checking. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 8 Rev. A
...signal. This element is a 10-channel, 8 bit, serial interface converter. All Z synchro outputs are grounded in the GAD 42. The SELECTED CRS DRIVE X/COS and SELECTED CRS DRIVE Y/SIN outputs have an additional circuit element not present on other ...by this device for the same purpose. This is set by this device reads all DC voltage monitoring in the GAD 42. 7.10 Digital-to the Analog PC board where they are protected from -1 (inverted) through 0 to +1 ...It is used for all internal DC voltages for validity checking. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 8 Rev. A
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...described previously. 7.15 ARINC 429 Receivers The GPS, NAV, Heading, and Radar Graphics ARINC 429 receivers are programmed by an 11.8 VDC regulator. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 9 Rev. Both FPGA's are all input to clock the two FPGA IC's. Three IC address latches latch CPU ...board contains the CPU which then turns on a PNP output transistor. This 16 MHz clock output is present anytime power is applied to the GAD 42, and is provided by serial data. A flash memory device contains unit software code, and can then pass data. After level shifting, both...
...described previously. 7.15 ARINC 429 Receivers The GPS, NAV, Heading, and Radar Graphics ARINC 429 receivers are programmed by an 11.8 VDC regulator. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 9 Rev. Both FPGA's are all input to clock the two FPGA IC's. Three IC address latches latch CPU ...board contains the CPU which then turns on a PNP output transistor. This 16 MHz clock output is present anytime power is applied to the GAD 42, and is provided by serial data. A flash memory device contains unit software code, and can then pass data. After level shifting, both...
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.... A unity-gain buffer which applies the signal to an op amp where it on the CPU board. The transition edges are within the feedback loop. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 10 Rev. 7.16 ARINC 429 Transmitters The GPS Lo-Speed and Hi-speed ARINC 429 transmitters are output from the...
.... A unity-gain buffer which applies the signal to an op amp where it on the CPU board. The transition edges are within the feedback loop. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 10 Rev. 7.16 ARINC 429 Transmitters The GPS Lo-Speed and Hi-speed ARINC 429 transmitters are output from the...
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... turn on the transistor, and the output normally connected to ground. When the HDG_VALID_HI input pin is turned off for the GAD 42. A diode provides transient voltage protection for the transistor. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 11 Rev. A capacitor and resistor form a low-pass filter to reduce high-frequency noise at logic...
... turn on the transistor, and the output normally connected to ground. When the HDG_VALID_HI input pin is turned off for the GAD 42. A diode provides transient voltage protection for the transistor. GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Page 11 Rev. A capacitor and resistor form a low-pass filter to reduce high-frequency noise at logic...
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A GAD 42 Block Diagram Page 12 Rev. HEADING X HEADING Y REMOTE CRS SELECT X/COS REMOTE CRS SELECT Y/SIN TRUE AIRSPEED X/SIGNAL TRUE AIRSPEED Y/REFERENCE RESERVED (SPARE X IN) RESERVED (... ARINC 561/568 DATA ARINC 561/568 SYNC DRIVER LEVEL SHIFT ARINC 561/568 CONTINUOUS CLOCK KING SERIAL DATA KING SERIAL CLOCK KING SERIAL SYNC GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Figure 1.
A GAD 42 Block Diagram Page 12 Rev. HEADING X HEADING Y REMOTE CRS SELECT X/COS REMOTE CRS SELECT Y/SIN TRUE AIRSPEED X/SIGNAL TRUE AIRSPEED Y/REFERENCE RESERVED (SPARE X IN) RESERVED (... ARINC 561/568 DATA ARINC 561/568 SYNC DRIVER LEVEL SHIFT ARINC 561/568 CONTINUOUS CLOCK KING SERIAL DATA KING SERIAL CLOCK KING SERIAL SYNC GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 Figure 1.
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... (2 PLCS) END PLATE 115-00265-00 SIDE EXTRUSION 135-00007-01 (2 PLCS) INSULATOR COVER 250-00064-00 (2 PLCS) BOARD HEADERS 334-00039-00 (3 PLCS) GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 COVER 115-00266-00 INSULATOR COVER (2 PLCS) 250-00064-00 (REF) INSIDE SURFACE ONLY SCREW 211-632340-06 (4 PLCS) ANALOG BOARD 012...-00 SCREW 211-602340-08 (33 PLCS) CPU BOARD 012-00299-00 HEX STANDOFF 214-00004-00 (4 PLCS) HEX SPACER 214-00020-04 (4 PLCS) Figure 2. A GAD 42 Assembly Drawing Page 13 Rev.
... (2 PLCS) END PLATE 115-00265-00 SIDE EXTRUSION 135-00007-01 (2 PLCS) INSULATOR COVER 250-00064-00 (2 PLCS) BOARD HEADERS 334-00039-00 (3 PLCS) GAD 42 MAINTENANCE MANUAL P/N 190-00159-01 COVER 115-00266-00 INSULATOR COVER (2 PLCS) 250-00064-00 (REF) INSIDE SURFACE ONLY SCREW 211-632340-06 (4 PLCS) ANALOG BOARD 012...-00 SCREW 211-602340-08 (33 PLCS) CPU BOARD 012-00299-00 HEX STANDOFF 214-00004-00 (4 PLCS) HEX SPACER 214-00020-04 (4 PLCS) Figure 2. A GAD 42 Assembly Drawing Page 13 Rev.