AA34 Series Universal Radio Interface
SM36 Installation and Operation Manual
Section 2 Rev: 1.01
Issue 4
Page 2-2
ENG-FORM: 805-0121.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.4.1
Warnings
N/A
2.4.2
Cautions
CAUTION:
Do not bundle
any lines from this unit
with transmitter coax lines. Do not
bundle any logic, audio, or DC power lines from this unit with 400 Hz synchro
wiring or AC power lines. Do not position this unit next to any device with a
strong alternating magnetic field such as an inverter, motor or blower, or
significant audio interference will result.
In all installations, use shielded cable exactly as shown, and
ground as
indicated
. Significant problems may result from not following these
guidelines.
Incorrect wiring and shielding, can seriously degrade audio installations and result
in abnormal cross-talk, hum and ground-loop noise. Be especially careful with all
microphone wiring, as these lines can carry the lowest level signals in the aircraft.
2.4.3
Cabling and Wiring
All wire shall be selected in accordance with the original aircraft manufacturer's Maintenance Instructions
or AC43.13-1B Change 1, Paragraphs 11-76 through 11-78. Unshielded wire types shall qualify to
MIL-W-22759 as specified in AC43.13-1B Change 1, Paragraphs 11-85, 11-86, and listed in Table 11-11.
For shielded wire applications, use Tefzel MIL-C-27500 shielded wire with solder sleeves (for shield
terminations) to make the most compact and easily terminated interconnect. Follow the interconnect
drawing in Section 2.7 as required.
Allow 3" from the end of the shielded wiring to the shield termination to allow the connector hood to be
easily installed. Refer to the interconnect drawing in Section 2.7 for shield termination details. Note that
the hood is a "clamshell" hood, and is installed after the wiring is complete.
Maintain wire segregation and route wiring in accordance with the original aircraft manufacturers
Maintenance Instructions.
Unless otherwise noted, all wiring shall be a minimum of 22 AWG, except power and ground lines, which
shall be a minimum of 20 AWG. Reference the Interconnect drawing for additional specifications. Check
that the ground connection is clean and well secured, and that it shares no path with any electrically noisy
aircraft accessories such as blowers, turn and bank instruments or similar loads. Power to this unit must
be supplied from a separate circuit breaker or fuse (fast blow), and not attached to any other circuit
breaker without additional protection. Verify that the selected circuit breaker size and wire gauge are
adequate for the installation using the techniques specified in AC43.13-1B Change 1, Paragraphs 11-47
through 11-51 and 11-66 through 11-69.