Specifications

AA21-400 Cabin PA System Manual SM34 Rev. 4.00
1.4 Specifications
1.4.1 Electrical Specifications
Power Supply Linear DC (with reverse & over voltage protection):
Normal: +27.5 Vdc nominal.
+22.0 Vdc minimum.
+30.3 Vdc maximum.
+18.0 Vdc emergency.
Input Current: 2.3 A max. full speaker power (35 W) @ +27.5 Vdc.
2.9 A max (35 W) with 0.40 A load on Switched
Power Output.
0.40 A idle @ +27.5 Vdc.
Backlighting: 150 mA max @ +27.5 Vdc.
Input Signals
Microphone: 150 Ohm amplified dynamic.
250 mVrms rated input level.
ALC Automatic level controlled for maximum intelligibility
without distortion starts @ 130 mVrms.
Impedance 130 Ohm ± 10%.
Music: Only one of Radio (Receive) or CD may be enabled at
a time.
Radio (Receive) 2.5 Vrms into 1k Ω ± 10%.
CD 1.0 Vrms into 11k Ω ± 10%.
PA key: Active low. Max. current source 15 mA.
+3dB key: Active open, isolated through optical relay. Max.
current source 13 mA. Reduces all audio, except
sidetone, by 3 dB when grounded. The output will be
reduced 2 to 3 dB if operating above 25 W on speaker
output, or above 6.5 Vrms on PA output.
Input to Input Crosstalk: ≤ -40 dB from rated output.
Page 1-2 Nov 10, 2003
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.