Specifications

SM34 Rev. 4.00 AA21-400 Cabin PA System Manual
Output Signals
Speaker: Impedance and short circuit protected.
≤ 10% THD 20 W single tone into 8 Ω @ 50% duty cycle. Continuous.
20 W voice/music into 8 Ω @ 100% duty cycle. Continuous.
Note: Distortion is ≤ 3% THD at 10% of continuous
output power rating.
> 10% THD 35 W max. into 8 Ω with 2.5 Vrms into Radio (Receive) input.
Non-continuous (short term).
Audio bandwidth: Mic input: ≤ 3 dB roll-off from 350 Hz to 3 kHz
Radio (Receive)/CD input: ≤ 3 dB roll-off from 350 Hz to 6 kHz
PA: Selectable by internal jumper for either
PA110/220 (6.5 Vrms ± 10% into 600 Ω) or
PA250/700 (0.5 Vrms ± 10% into 600 Ω) for rated output.
Distortion: ≤3% THD at rated output.
Audio bandwidth: Mic input: ≤ 3 dB roll-off from 350 Hz to 3 kHz
Radio (Receive)/CD input: ≤ 3 dB roll-off from 350 Hz to 6 kHz
Siren: Only available on PA output (735 to 1620 Hz). Yelp
and wail modes with adjustable rates. Siren level
control provided for yelp/wail by one internal trimpot.
Sidetone: Adjustable 0-100 mW into 600 Ω with ≤ 10% THD
Audio bandwidth: ≤ 3 dB roll-off from 350 Hz to 3 kHz
Input to Output ≤ -50 dB from rated output.
Crosstalk:
Audio Noise Level: ≤ -50 dB from rated output.
(without signal)
Switched Power: +27.5 Vdc @ 0.40 Amps max. Over current protected.
Temperature Sensor The unit contains a temperature sensor IC which
when triggered reduces the input signals by 3 dB.
The IC threshold is set to approximately 130° C.
Annunciator Power On (illuminates green when active)
Nov 10, 2003 Page 1-3
ENG-FORM: 800-0106.DOT Amendment #2 May 24, 2006
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.