AMS44 and AMS44T Dual Channel Audio Controllers

AMS44 and AMS44T Dual Channel Audio Controllers
AMS44 and AMS44T
Dual Channel Audio Controllers
OPERATOR’S MANUAL
REV 1.11
December 4, 2002
Northern Airborne Technology Ltd.
1925 Kirschner Road
Kelowna, BC, Canada.
V1Y 4N7
Telephone (250) 763-2232
Facsimile (250) 762-3374
Copyright 2002 by Northern Airborne Technology Ltd.
Table of Contents
1
Introduction ......................................................................................1
2
General Operation ...........................................................................1
2.1
Audio Alerting Functions.............................................................1
2.2
Selection of Transmit Functions .................................................2
2.2.1
Transmit Selectors ................................................................2
2.2.2
Hand Microphone..................................................................2
2.3
Transceiver Receive Functions ..................................................3
2.3.1
Receive Selection Switches ..................................................3
2.3.2
Transceiver Selection Examples ...........................................3
2.3.3
Volume Controls....................................................................4
2.3.4
Passenger Receive Audio Selection .....................................4
2.3.5
Auxiliary Inputs......................................................................4
2.4
Intercom Functions .....................................................................4
2.4.1
ICS Modes of Operation........................................................5
2.4.2
Passenger ICS Operation .....................................................5
2.5
Mode Control ..............................................................................6
2.5.1
Emergency Operation ...........................................................6
2.5.2
Isolation Operation ................................................................6
3
Specifications...................................................................................7
3.1
Electrical Specifications..............................................................7
3.2
Physical Specifications ...............................................................7
3.3
Environmental Specifications .....................................................7
1
Introduction
This manual contains operating instructions and specifications for the AMS44 and
AMS44T Dual Channel Audio Controllers. The controls and legends for both models
are identical.
2
General Operation
The AMS44 and AMS44T provide one central controller for all the aircraft audio,
allowing selection of transmit and receive audio, LIVE, PTT (Keyed), or VOX intercom,
interface for an additional handheld transmit microphone (hand mic), and pilot/copilot
isolation/ emergency operation. Typical definition of the unit has the ‘pilot’ on the right
side of the controller, and the ‘copilot’ and passengers on the left side. This can be
easily re-configured at the time of installation for alternate seating arrangements.
Individual control over receive and transmit functions are provided for both the pilot and
copilot (observer), and a common control is provided for LIVE, PTT and VOX ICS
operation. An additional control is provided for NORMAL, EMERGENCY, or ISOLATE
(pilot cut off from ICS audio) operation.
Sidetone (S/T) level is adjustable internally, and Receive (RX) and Intercom (ICS) levels
are adjustable on the front panel. All audio, except the S/T of the radio IN USE and any
Type ‘B’ DIRECT AUDIO input signals, are muted during transmit for clarity. ICS
operation allows transmit during any ICS mode by using the PTT switch.
2.1
Audio Alerting Functions
No internal audio alerting is provided in the AMS44 or AMS44T. Two direct
(unswitched) inputs are provided to allow airframe alerting signals to be routed to the
pilot. See 2.3.5 (Auxiliary Inputs) for more information. DIR AUD #1 is amplified by the
Audio controller, and can not be heard when the Mode Switch is in the EMER position.
DIR AUD #2 is not amplified, and is audible at all times.
Page 1
2.2
Selection of Transmit Functions
Transmit
Annunciator
2.2.1
Left User (Co-pilot)
Transmit Selector
Right User (Pilot)
Transmit Selector
Transmit
Annunciator
Transmit Selectors
The transmit selector controls are six position rotary switches, one on each side of the
panel to correspond to the user on that side of the aircraft. The controls select the
transmit function required by the relevant user. Each rotary selector switch is
completely independent of the other, and the pilot and copilot have equal priority during
transmit. When the PTT is activated, all audio selected on the side of the controller that
is transmitting is muted, except the sidetone of the transceiver in use.
2.2.1.1
Automatic Receive Audio
Receive audio is automatically selected as a function of the respective rotary selector
switch. No additional switching is needed to establish external communication.
2.2.1.2
Transmit Annunciator
During transmit from either the pilot or copilot position, the appropriate TX annunciator
(green) will light on the front panel.
2.2.1.3
TX Selector Example
In the figure that follows, the positions of the rotary selector switches indicate that the left
and right sides of the controller are set for transmit operation on the AUX FM transceiver.
Both Transmit Selectors at AUX FM
2.2.2
Hand Microphone
The hand mic functions without power and will work in emergency or equipment failure
situations. The hand mic normally functions on the left side of the controller but can be
connected to the right side at the time of installation by changing an internal switch. When
the hand mic or transmit PTT switch is activated, the mic involved will be coupled to the
radio (or PA) selected. The TX annunciator will not light when the hand mic is used.
Page 2
2.3
Transceiver Receive Functions
2.3.1
Receive Selection Switches
The Receive Audio select switches (white switch bats) are ‘center-off’ type with the ‘up’
position selecting the respective navaid receiver audio, and the ‘down’ position
selecting the respective transceiver audio. See section 2.3.3.1 for RX volume control.
2.3.2
Transceiver Selection Examples
In the figure below, the right TX selector is set for transmit and receive operation on the
AUX FM. The Receive function switches are also selected so the right side can monitor
COM1 and FM2 transceivers as well as NAV1 and DME navaids. Note that PA, COM2,
FM1, NAV2, ADF, and MKR are not selected.
Receive Switches at
Navaids NAV1 and DME
Receive Switches
monitor COM1 and FM2
Transmit Selector at AUX FM
In the figure below, the right side configuration remains the same. The left side is set
up to receive and transmit on COM2 while monitoring COM1 and FM2 transceivers as
well as the MKR navaid. Note that FM1, AUX FM, PA, NAV1, NAV2, ADF and DME
are not selected on the left side.
Receive Switches
monitor COM1 and FM2
Receive Switch
at Navaid MKR
Transmit Selector at COM2
Volume Controls
(RX and ICS VOL)
Page 3
2.3.3
Volume Controls
The controller features individual master RX and ICS VOL controls on both the left
and right sides of the unit, which can be adjusted to suit the specific user's
requirements.
2.3.3.1
RX Volume Control
The RX knobs are the smaller, topmost controls of the dual concentric volume control
assemblies. The RX VOL controls provide adjustment of the RX audio selected by the
controller from 10% to full. As in any audio system, it is important to set the individual
radio volume controls to a nominal level that is acceptable to both pilots, then adjust the
respective master RX VOL on the audio controller to suit user preference. The RX VOL
controls are designed to provide a minimum level, even when set fully ccw.
All receive audio is muted during transmit (NORM and ISO mode).
2.3.3.2
ICS Volume Control
The ICS VOL knobs are the larger, bottom controls of the dual concentric volume
control assemblies. The ICS VOL controls provide adjustment of the ICS audio
selected by the controller. The ICS volume controls provide adjustment from 0 to full
output. See also section 2.4.
2.3.4
Passenger Receive Audio Selection
The passengers normally hear the radio audio as selected on the left side of the
controller. The passengers can be shifted to the right side by changing the setting of the
internal PAX switch, accessible through the right side of the controller. The passengers
will not hear any radio audio when the red mode switch is in the EMER position.
2.3.5
Auxiliary Inputs
Two Direct Audio inputs are available. They are coupled directly to either the left or right
side of the controller at the time of installation. The Direct Audio inputs are normally
selected for the right side of the controller when the unit is shipped from the factory.
2.4
Intercom Functions
All ICS audio is controlled by the front panel ICS volume controls and may be varied to
suit conditions. There are independent volume controls for the left and right sides of
the controller. The ICS VOL are the larger, aft controls of the dual concentric volume
control assemblies. See also section 2.3.3.2.
If the controller is operated in the emergency mode, ICS operation will continue (if there is no
fault condition) between the passengers, but not between the pilot and copilot or passengers.
Page 4
2.4.1
ICS Modes of Operation
Intercom system (ICS) audio may be implemented in three modes between users; LIVE
(on constantly), VOX (voice activated), or PTT (active only when switched by ICS PTT
switch). The ICS mode is selected by the control (labeled ICS) in the middle of the top
switch row. It is common to use the LIVE mode during ground operations, start-up, etc.,
and to use VOX or PTT operation if conditions are so noisy that ‘pilot fatigue’ will result.
ICS Mode Control
The desired ICS mode is selected by the ICS mode control knob.
PTT ICS (KEYED Operation)*
ICS Mode Control set fully counter-clockwise into the switch detent.
LIVE (Hot Mic Operation)
ICS Mode Control set fully clockwise.
VOX (Voice Activated)
ICS Mode Control set fully clockwise, then slowly rotated counter-clockwise until
the intercom just becomes ‘quiet’. This setting will vary with ambient noise
conditions, and the quality and number of microphones connected in the system.
* KEYED operation is inherent to the pilot and copilot microphone circuits only.
2.4.2
Passenger ICS Operation
Passenger ICS audio is LIVE when the controller is in the LIVE or PTT mode of ICS
operation and are VOX triggered when a VOX setting is selected. Note that the
passengers are always LIVE unless interrupted by an in-line PTT cord, or the controller
is set for VOX operation.
Passenger and copilot (observer) operations can be maximized by using PTT type cord
assemblies designed for use with NAT audio controllers.
CAUTION: Ensure that all PTT type cord assemblies have properly shielded mic and
phone wiring, or ‘crosstalk’ will occur.
Page 5
2.5
Mode Control
Mode Control Switch
The Mode Control switch is a three-position, locking toggle switch that is used to select
between ISO, EMER OPER, and NORM. It is identified with a red cap.
2.5.1
Emergency Operation
The center (EMER OPER) position of the mode switch places the controller into the
emergency operation mode. When switched to the EMER OPER position, both pilot and
copilot controls are removed from the ICS bus and connected directly to their respective
radios. This mode should be selected in the event of a box fault or power failure.
The Emergency function should be tested prior to flight to assure proper operation and
allow the radio levels to be set adequately for emergency operation.
2.5.1.1
Emergency Mode Effects
In the EMER mode, all functions are retained by the pilot and copilot, except ICS and
possibly boom mic operation. If the box or airframe fault prevents the TX annunciator
from lighting during transmit (indicating a failure in the mic keying circuit), then the hand
mic should be used. A power fault of any kind will prevent the TX annunciator from
lighting, giving an immediate indication of failure. If ICS audio is still available, then the
power to the controller has not failed and loss of the TX light indicates TX switch failure.
Note that in the EMER mode, all switches work exactly as they do during NORM operation,
except for the RX and ICS volume controls, which will have no effect.
Any selected receive audio is switched to the appropriate user in the ‘emergency’ mode (red
mode switch in the EMER position), but not to any passengers in the system. Level will be
lower than NORM operation because the signals are obtained directly from the radios,
bypassing the electronics in the controller. This is provided for failure situations that make
operation impossible in the NORM mode (i.e., loss of power or amplifier failure, etc.)
2.5.2
Isolation Operation
The mode switch can select an ISO function, which prevents the selected user from
receiving ICS audio. This is useful when passengers are interfering with critical flight
operations (landing, etc.). It can be preselected at installation to isolate the left or right side.
Intercom operation for the passengers and copilot is not affected. It is normally set for
isolation of the right side when the unit is shipped from the factory.
Page 6
3
Specifications
3.1
Electrical Specifications
3.2
Input Power
Typically +22 to +32 Vdc at 250 mA
Nominal +28 Vdc
Lighting
160 mA at 28 Vdc.
600 mA at 5 Vdc.
Mic Requirement
‘Carbon equivalent’ 250 mV into 150 W min.
(David Clark M1/DC, M3, M4, M7 recommended)
RX Audio Requirement
25 mW into 600 W
Headset Power
250 mW per channel into 600 W
Key Logic
Ground seeking for all lines.
‘Hard’ ground outputs to all transceivers.
TX LED on front panel lights when any transmit
key input is low except hand mic.
Cross-Talk
De-selected inputs 50 dB min. below full output
Bi-direc. ICS Tie Line
340 mVrms for full output
1.6 kW input impedance
Physical Specifications
Height
Depth behind panel
Width: front panel
rear enclosure
Weight
Mounting
3.3
AMS44
1.88" (47.8 mm) max.
6.77" (172.0 mm) max.
excl. mating connectors
5.75" (146.1 mm) max.
5.00" (127.0 mm) max.
2.3 lbs (1.04 Kg)
Dzus Mount
(four fasteners)
AMS44T
2.18" (55.4 mm) max
7.50" (190.5 mm) max
excl. mating connectors
6.28" (159.5 mm) max.
6.02" (152.9 mm) max.
2.65 lbs (1.2 kg)
Tray Mount
Environmental Specifications
Temperature
-20 to +55° C (ambient)
-55 to +85° C (survival)
Altitude
25,000 feet max.
Humidity
95% Non-condensing
Shock
AMS44
AMS44T
12g (any axis)
6g (any axis)
Vibration
AMS44
AMS44T
Conforms to DO-160B category ‘P’
Conforms to DO-160D category ‘SM’
Page 7
NOTES
Page 8
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement