Northern Airborne Technology AMS50 - Manual (Page 20)

AMS50-000 Stereo Audio Panel with Marker Manual SM50 Rev. 4.00
Page 2-2 Nov 12, 2003
ENG-FORM: 805-0104.DOT
Amendment #1 Jan 18, 2005
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.3.2 Cautions
How and where grounds are tied together is very important in an audio panel
installation. Twisted shielded paired wires shall be used for all audio lines from radios
that have separate audio HI/LO connections. In all cases, the shield on these lines shall
be grounded at both ends of the cable.
⇒ In all installations, use shielded cable exactly as shown and ground as indicated.
Significant ground loop and noise problems may result from not following these
guidelines.
⇒ Do not ground the microphone or headphone jacks.
⇒ Do not connect the microphone and headphone shields together.
⇒ Use caution when routing microphone wiring as it carries low level signals prone
to coupling from other sources.
⇒ Do not take a ground from the instrument panel or similar location that shares a
ground return with a turn and bank, horizon or other motor driven instrument.
This may cause the unit to pick up the sound of the motor as ground loop
interference.
2.3.3
Cabling and Wiring
All unshielded wire shall be selected in accordance with AC43.13-1B Change 1,
Paragraphs 11-76 through 11-78. Wire types should be 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 wiring diagrams in Section 2.5 as required.
All wiring should be at least 22 AWG, except power and ground lines which should be at
least 18 AWG. Ensure that all ground connections are clean and well secured.
To prevent system failure or inadequate equipment protection, supply power from a
separate 3.0 Amp breaker not connected to any other source.
The AMS50 uses a special connector that mates directly with the printed circuit board
inside the unit.