Honeywell International Inc. DMA-37B2 Manuale Utente

Page 15

10 Oct 2007

DMA-37B DME System

© Honeywell International Inc. Do not copy without express permission of Honeywell.

(1) The DMA-37B DME Interrogator is packaged in an ARINC 600 Characteristic, 4 MCU 

standard form factor case. It contains the electronics required to transmit and receive the 

pulse modulated L-band signal required by the ground station transponder and to 

interface with the aircraft systems.

(2) The basic -0101, -0202, and -0303 DMA-37B consists of a RF module, a 

synthesizer/modulator module, a video processor module, CPU-I/O module, power 

supply assembly, HIRF/rear interconnect assembly, front panel assembly, and memory 

card interface module (see Figure 4).

(3) The basic -1101 and -1212 DMA-37B consists of a RF assembly, an integrated video 

main processor assembly, a variable frequency power factor corrected power supply 

assembly, a rear interconnect assembly containing lightning protection, and a front panel 

assembly (see Figure 4).

(4) The DMA-37B uses a low insertion force, size two shell, ARINC 600 rear panel 

connector with three inserts. The top insert is not used. The middle insert is used for 

aircraft interconnections and coaxial antenna connector, and the bottom insert is used 

for input power and suppression coaxial connectors. The keying pins are set to index pin 

code 03.

(5) Forced air cooling, in accordance with ARINC specification 600, is required for cooling 

the DMA-37B. 

(6) Data interfaces to the aircraft systems are through slow-speed ARINC 429 ports.
(7) A variety of discrete and strap pins provide additional information to and from the DME.
(8) The -0101, -0202, and -0303 front panel display provides an interface to an operator with 

a liquid crystal display (LCD) that is visible from the front of the DMA-37B to display 

messages in simple language in one of four modes: normal operation, BITE display, 

maintenance, and software loading.

(9) Software loading and data recording to/from the CPU is through the front panel Personal 

Computer Memory Card International Association (PCMCIA) slot. Intel Series 2 Flash 

Cards with capabilities ranging from 1, 2, or 4 megabytes are supported.

(10) Intel Series 2 Flash Cards with capabilities ranging from 4, 10, and 20 megabytes (up to 

64 megabytes, when available) are also supported.

(11) Two pushbutton switches allow operator interface with the DMA-37B LCD.
(12) In normal operation, the front panel LCD displays the unit's characteristics: unit 

identification, part number, and serial number (-0101, -0202, and -0303 only). The BITE 

display mode is activated after manual self-test has been exercised either from the front 

panel test pushbutton or remotely. In the BITE mode, BITE status is reported and, in the 

event of a detected failure, additional help screens are provided to locate the detected 

failure to a module. BITE help pages are provided. In the maintenance mode, a set of 

maintenance words are displayed and decoded showing the names of data fields and 

the value of the data. Maintenance help pages are provided. For loading software, a 

series of screens direct the operator during the data loading process. Software version 

and loading status are provided during the update process.

(13) The -1101 and -1212 front panel assembly consists of three easy to see LED indicators 

that display the status of the unit.

(1) Other DMA-37B DME System components are not supplied by Honeywell. Information 

on these units must be obtained from their respective manufacturers.