Air Comm Systems ACS 775SL-SP User manual

Air Comm Systems, Inc
37610 Sky Canyon Dr., Hangar 51
Murrieta, CA 92563
Ph: 951-677-0101 ~ Fx: 951-677-0701
[email protected] ~ www.AirCommSystems.com
Single Audio Mixer Panel
Installation and Operations Manual
ACS 775SL-SP (A692-7) RHC Revision 2.9
VOLUME
OFF
NORM
EMER
MIC SEL
COM
COM
123
PA
123
Air Comm
ACS 775SL
XMIT

Air Comm Systems, Inc. Page 2
n
Installation
Physical and Operating Specifications Page 3
Physical Dimensions Page 4
Interface Schematic Page 5
n
Operation
Front Panel Controls Page 6-7
Front and Rear Panel Controls Pictorial Page 8
n
Warranty Information
Warranty Information Page 9
ACS 775SL-SP Installation and Operations
Manual Table of Contents

Air Comm Systems, Inc. Page 3
n
Physical Specifications
n
Operating Specifications
ACS 775SL-SP Installation and Operations
Manual Physical and Operating Specifications
SIZE: 5.75 in. (14.61cm) W
1.50 in. ( 3.81 cm) H
6.78 in. (17.22cm) D
WEIGHT: 1.50lb. (.68kg)
MOUNTING: Dzus rail mount
CONTROLS: Panel mounted - transmit = rotary switch, audio inputs = toggle switch,
volume control = dual potentiometer
ILLUMINATION: Edge lit front panel per MIL-P-7738E, type 3. Capable of
connection to dimmer bus for adjustment. Amber transmit light indicates
when unit is in transmit mode.
INPUTS: 4 selectable receive audio inputs and up to 5 transmit selections.
DUTY CYCLE: Continuous POWER REQUIREMENTS: 28 VDC
MAXIMUM OPERATING ALTITUDE: 16,500 ft.(5029 m)
OPERATING TEMPERATURE RANGE: -40 C to +85 C (operating)
-65 C to +125 C (storage)
CURRENT DRAIN: 70 mA at 28V (standby) - 500mA at 28V (max. signal)
AUDIO OUTPUT: Minimum 250 mW into 600 ohms
FREQUENCY RESPONSE: Within 6 db - 300-3000Hz
ICS INPUT IMPEDANCE: 600 ohms
RECEIVER INPUT IMPEDANCE: 600 ohms - matched to receiver
INPUT ISOLATION: Not less than 50 db between inputs
AUDIO MUTING: Not less than 40 db during transmit/ICS (optional)
MIC SENSITIVITY: 300 mV for rated output
DISTORTION: Less than 10% at 1000 Hz for maximum output

Air Comm Systems, Inc. Page 4
Physical Installation
The ACS 775SL-SP is designed to be Dzus mounted and should be installed in the aircraft
using the Installation kit that is included. The above outline drawing of the unit with
dimensions will facilitate the installation. Be sure that adequate clearance is allowed for the rear
connector and cable harness.
The connector pin configuration of the ACS 775SL-SP rear connector and the recommended wire
size for the aircraft cable harness is shown on the following page.
n
Physical Dimension Outline for mounting
ACS 775SL-SP Installation and Operations
Manual Physical Dimensions
Unit Width Behind Face Plate
Front Panel Width - Standard Dzus Mount
Allow up to 2.500" For Rear Connector and Cable Clearance
VOLUME
OFF
NORM
EMER
MIC SEL
COM
COM
123
PA
123
Air Comm
ACS 775SL
XMIT

Air Comm Systems, Inc. Page 5
The ACS 775SL-SP wiring harness should be constructed of Tefzel aircraft wire (M22759/16 grade
or better). Power and ground wires should be 18 or 20 AWG, and all other wires may be 22 AWG.
Shielded wires should be used where noted. Adequate protection against wear and chafing should be
taken by using a braided cable sleeving or jacket. Before completing installation, verify that all cable
connector pins are seated properly and that the connector is securely mounted to the unit mating
connector. Important - please note the power of the unit before installing; it will be either 14VDC or
28VDC and clearly marked as such on the units data tag.
Pre-fabricated cable harnesses are available from Air Comm to expedite installation - consult our
sales department for details.
n
Connector Pin-out
ACS 775SL-SP Installation and Operations
Manual Interface Schematic

Air Comm Systems, Inc. Page 6
ACS 775SL-SP Installation and Operations
Manual Front Panel Controls
(See figure 1 - Page 8 for pictorial)
Description
The ACS 775SL-SP Single Audio Mixer Panel is a compact, lightweight unit which
provides full audio control for a single position in the aircraft. It has the
capability to provide its user with 4 receive audio selections, 5 transmitter
selections, and full headphone audio and ICS volume control.
1- NORM - EMER SWITCH
This switch controls the operation of the audio panel in the event of an audio
amplifier failure. In the “up" position (NORM) the audio panel is in normal operating
mode. In the “down" position (EMER) all audios are summed and then fed directly
to the headphones. This enables the use of the transmitters and other equipment
during audio amplifier failure.
2 - RECEIVE AUDIO SELECT-MUTE SWITCHES
Normal operation - In the “up" position the audio selected is channeled to
its proper headphone. In the “down" position the audio selected is muted.
Emergency operation - In the “up" position the audio selected is muted. In the
"down" position the audio selected is summed with any other audios selected and
then sent to the headphone.
3 - HEADPHONE VOLUME CONTROLS
This concentric knob adjusts headphone volume and adjusts the radio volume.
Clockwise rotation increases the volume - counter clockwise rotation decreases the
volume. In the event of excessive or inadequate receiver volume the pots located
on the rear of the unit may be adjusted for the proper level. (see FIGURE 2)

Air Comm Systems, Inc. Page 7
ACS 775SL-SP Installation and Operations
Manual Front Panel Controls (cont’d)
(See Figure 1 - Page 8 for pictorial)
4 - LIGHTING
The audio panel is lit by two 28V (P/N 327) lamps which provide night time visibility
for all panel legends. These lamps may be replaced in the event of a failure by
unscrewing the front panel mounted filter cap, inserting a new lamp, and reinserting
the filter into the front panel.
5 - MIC SELECTOR
This rotary switch performs three functions simultaneously. It (a) connects the mic to
the selected transmitter (b) selects the associated key line, and (c) selects the
associated audio (if not already selected using the audio select-mute switch).
6 - TRANSMIT INDICATOR
When the transmit key is activated this indicator lights up showing that the audio
panel is in the transmit mode.

Air Comm Systems, Inc. Page 8
n
Figure 1 - Front Panel Controls
ACS 775SL-SP Installation and Operations
Manual Front Panel Controls
n
Figure 2 - Rear Panel Controls
28V
VOLUME
OFF
NORM
EMER
MIC SEL
COM
COM
123
PA
123
Air Comm
ACS 775SL
XMIT

Air Comm Systems, Inc. Page 9
ACS 775SL-SP Installation and Operations
Manual Warranty Information
LIMITED WARRANTY
Air Comm Systems, Inc. warrants each new product to be free from defective material and
workmanship and agrees to remedy any defect or to furnish a new part in exchange for any
defective unit provided an examination discloses such defect occurred under normal use and service,
and provided the defective unit is delivered to us, with transportation charges prepaid, within 1 year
from the date of acceptance of equipment by the owner. Each unit required and claimed defective
must be returned to:
Air Comm Systems
37610 Sky Canyon Dr., Hangar 51
Murrieta, CA 92563
Ph: 951-677-0101
Fx: 951-677-0701
E-Mail: [email protected]
Attn: Service Dept.
This warranty does not extend to any products which have been subjected to misuse, neglect,
accident, or in violation of instructions furnished, nor does it extend to units which have been repaired
or altered outside of our factory except where such repairs are specifically authorized in writing by us.
This warranty is in lieu of all other warranties expressed or implied, and no representative or
person is authorized to assume for us any other liability in connection with the sale of our products.