ACR&Artex ELT to Nav Interface Boeing - Manual (Page 24)

ACR ELECTRONICS, INC / ARTEX PRODUCTS
ABBREVIATED COMPONENT MAINTENANCE MANUAL
-B (453-6501)
25-69-11
Page 24 of 58
JUL 28/11
SUBTASK 25-69-11-870-002
B. Physical Description
(1) The ELT/NAV Interface -B components are housed in a 0.125 inch (3.2 mm) thick aluminum
chassis; finished with a chromate conversion primer and a safety orange, high solids epoxy or
polyurethane finish. See "Figure 2. ELT/NAV Interface -B Isometric View".
Figure 2. ELT/NAV Interface -B Isometric View
SUBTASK 25-69-11-870-003
C. Position Data Functionality
(1) The ELT/NAV Interface -B receives position coordinates (latitude and longitude) from the
aircraft onboard navigation system.
(2) The ELT/NAV Interface -B is capable of receiving data from the aircraft navigation system via
the following protocols:
(a) ARINC 429 - See SUBTASK 25-69-11-870-001, on page 26, for requirements.
(b) RS-232 - See SUBTASK 25-69-11-870-002, on page 26, for requirements.
(3) The ELT/NAV Interface -B converts the position data to a format compatible with the ELT and
forwards the data to the ELT via a second RS-232 port.
(4) The ELT must be programmed with a location protocol (long message format) in order to
receive, assimilate, and broadcast position data provided by the ELT/NAV Interface -B.
(5) The ELT stores the position data in RAM and broadcasts the position data, along with
identification data, when the ELT is activated.
(6) Position data is continually updated and overwritten in the ELT RAM as long as the ELT is idle
and waiting for an activation signal.
(7) If power to the ELT/NAV Interface -B is lost, the ELT holds the last known position data for 30
seconds and the ELT must be activated within that time frame to transmit position
information.