Northern Airborne Technology AA20 - Manual (Page 29)

AA20 Series PA/Siren System
SM33-1 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 4 Page 3-3
3.3.3 Volume Control
The volume level is set by the VOL pot on the front of the AA20. For external paging and rebroadcast
operations, the volume should always be set between half and full level. The setting for internal paging
must be determined by experiment to provide the desired coverage in the passenger area and to prevent
feedback.
Volume Control
3.3.4 External Siren
The external siren is operated by depressing the SIREN button on the front of the AA20, or by a remote
keying switch. The siren will sound only as long as the button is depressed.
Siren Button
If the siren does not suit the specific requirements of a given installation, the base tone, sweep rate and
siren level may be adjusted by your installer.
3.3.5 Remote Power Switch
The AA20 provides a switched 28 Vdc output that can be used to control the dc power circuit of a PA110
or PA220.
Section 3 ends
ENG-FORM: 806-0111.DOT
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