Honeywell International Inc. DMA-37B2 User Manual

Page 14

10 Oct 2007

DMA-37B DME System

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

(5) An automatic self-test feature is also built into the DMA-37B. This test is controlled by 

the microprocessor program. Approximately once every 1.5 seconds the program 

automatically instructs the unit to go into self test. The results of the test are monitored 

and compared against information stored in memory. If any results of the test indicate a 

malfunction, a DME invalid flag is generated and routed to DME distance users through 

the ARINC 429 output.

(6) The DME ground station transmits a station-identification signal along with the other 

data. The DMA-37B detects the station-identification signal and applies it to the aircraft 

audio system. 

(7) The DMA-37B generates a suppression pulse for internal use and also makes the pulse 

available at the rear connector of the unit. The pulse can be used to suppress other 

receivers when DME interrogation pulses are being transmitted. The DMA-37B can also 

receive suppression pulses from external equipment on the mutual suppression line.