9800 Martel Road
Lenoir City, TN 37772
www.ps-engineering.com
P
P
Audio Selector Panel with Marker Beacon Receiver
System Installation and Operation Manual
Patented under one or more of the following;
M
M
High-fidelity Stereo Intercom
FAA-Approved TSO C50c, C35d
No. 5,903,277; 6,160,496 and 6,493,450
A
A
Document P/N 200-890-0000
Revision 10, September 2005
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8
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In certified aircraft, warranty is not valid unless this product is installed by an
Authorized PS Engineering dealer.
PS Engineering, Inc. 2005 ©
Copyright Notice
Any reproduction or retransmittal of this publication, or any portion thereof, without the expressed written permission of PS
Engineering, Inc. is strictly prohibited. For further information contact the Publications Manager at PS Engineering, Inc., 9800
Martel Road, Lenoir City, TN 37772. Phone (865) 988-9800, email contact@ps-engineering.com.
Table of Contents
Section I GENERAL INFORMATION..................................................................... 1-1
1.1 INTRODUCTION.........................................................................................................................1-1
1.2 SCOPE............................................................................................................................................ 1-1
1.3 EQUIPMENT DESCRIPTION....................................................................................................1-1
1.4 APPROVAL BASIS – ............................................................................................................... .... 1-2
1.5 SPECIFICATIONS.......................................................................................................................1-2
1.6 EQUIPMENT SUPPLIED............................................................................................................1-4
1.7 EQUIPMENT REQUIRED BUT NOT SUPPLIED................................................................... 1-4
1.8 LICENSE REQUIREMENTS......................................................................................................1-4
Section II - Installation ..............................................................................................2-1
2.1 GENERAL INFORMATION....................................................................................................... 2-1
2.1.1 SCOPE ...........................................................................................................................2-1
2.1.2 CERTIFICATION REQUIREMENTS .................................................................................... 2-1
2.2 UNPACKING AND PRELIMINARY INSPECTION ................................................................................2-1
2.3 EQUIPMENT INSTALLATION PROCEDURES ....................................................................................2-1
2.3.1 COOLING REQUIREMENTS .............................................................................................. 2-1
2.3.2 MOUNTING REQUIREMENTS........................................................................................... 2-1
2.3.3 AUDIO PANEL MOUNTING RACK INSTALLATION .......................................................... 2-1
2.3.4 AUDIO PANEL TRAY AND CONNECTOR ASSEMBLY ....................................................... 2-2
2.4 CABLE HARNESS WIRING...............................................................................................................2-2
2.4.1 NOISE ............................................................................................................................. 2-2
2.4.2 EXISTING GMA340 INSTALLATION ............................................................................... 2-3
2.4.3 POWER............................................................................................................................ 2-3
2.4.4 COMMUNICATIONS PUSH-TO-TALK ............................................................................... 2-3
2.4.5 AUDIO PANEL INTERFACE .............................................................................................. 2-3
2.4.6 TEL (DUPLEX) FUNCTION FOR CELL PHONES............................................................... 2-3
2.4.7 TRANSMIT INTERLOCK ................................................................................................... 2-4
2.4.8 PATENTED "SWAP" MODE ............................................................................................. 2-4
2.4.9 BACKLIGHTING .............................................................................................................. 2-4
2.4.10 UNSWITCHED INPUTS ................................................................................................... 2-4
2.4.11 PUBLIC ADDRESS MODE .............................................................................................. 2-5
2.4.12 PA MUTE (J2, PIN 12) .................................................................................................. 2-5
2.4.13 MISCELLANEOUS LOGIC OUTPUT (J2, PIN 18)............................................................. 2-5
2.4.14 INTERCOM WIRING ....................................................................................................... 2-5
2.4.15 PLAYBACK BUTTON INSTALLATION (J2, PIN 22- OPTION 1, ONLY)........................... 2-7
2.5 MARKER BEACON INSTALLATION..................................................................................................2-7
2.5.1 MARKER ANTENNA INSTALLATION ............................................................................... 2-7
2.5.2 EXTERNAL MARKER LIGHTS.......................................................................................... 2-7
2.5.3 MIDDLE MARKER SENSE (MARKER VERSION)............................................................... 2-7
2.6 ADJUSTMENTS.................................................................................................................................2-7
2.7 COMMUNICATIONS ANTENNA INSTALLATION NOTES...................................................................2-8
2.7.1 AUDIO ACTIVE OUTPUT ................................................................................................. 2-8
2.8 PMA8000 PIN ASSIGNMENTS .........................................................................................................2-9
2.9 POST INSTALLATION CHECKOUT................................................................................................. 2-10
2.10 UNIT INSTALLATION................................................................................................................... 2-10
2.11 OPERATIONAL CHECKOUT......................................................................................................... 2-10
2.11.1 REQUIRED TEST EQUIPMENT ..................................................................................... 2-10
2.11.2 AUDIO PANEL TEST.................................................................................................... 2-10
2.11.3 MARKER CHECKOUT .................................................................................................. 2-11
2.11.4 TEL CHECKOUT ......................................................................................................... 2-11
PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
2.11.5 INTERNAL RECORDER CHECKOUT (OPTIONAL) ......................................................... 2-11
2.12 FINAL INSPECTION......................................................................................................................2-11
Section III OPERATION........................................................................................... 3-1
3.1 SCOPE............................................................................................................................................ 3-1
3.2 POWER SWITCH (1) (EMG-FAIL SAFE OPERATION) .................................................................... 3-1
3.3 MICROPHONE (2) (XMT) SELECTION (ALL MODELS)..................................................................3-1
3.3.1 SWAP MODE (SWITCH FROM COM 1 TO COM 2 REMOTELY) ......................................... 3-2
3.4 AUDIO SELECTOR (4)......................................................................................................................3-2
3.4.1 SPEAKER AMPLIFIER (5)................................................................................................. 3-2
3.5 SPLIT MODE.................................................................................................................................... 3-3
3.5.1 MUTE BUTTON, SPLIT MODE ICS (6) ............................................................................ 3-3
3.6 INTERCOM OPERATION .................................................................................................................. 3-3
3.6.1 INTELLIVOX® VOX-SQUELCH ....................................................................................... 3-3
3.6.2 INTERCOM VOLUME CONTROL (7)................................................................................. 3-4
3.6.3 INTERCOM MODES (8) .................................................................................................... 3-4
3.7 TELEPHONE MODE (9)....................................................................................................................3-5
3.8 MARKER BEACON OPERATION (10)...............................................................................................3-6
3.9 INTERNAL RECORDER SYSTEM (OPTION 1)...................................................................................3-6
3.10 OPERATION ...................................................................................................................................3-6
Section IV- Warranty and Service ............................................................................. 4-1
4.1 WARRANTY .....................................................................................................................................4-1
4.2 FACTORY SERVICE..........................................................................................................................4-1
Appendix A External PTT Hook Up ........................................................................... A
Appendix B – PMA 8000 Installation Drawings..........................................................B
Appendix C, J1 Interconnect ........................................................................................C
Appendix D, J2 Connector Interconnect...................................................................... D
Appendix E- Instructions for FAA Form 337 and continuing airworthiness ............... E
9.1 INSTRUCTIONS FOR FAA FORM 337, AUDIO PANELS ......................................................................E
9.2 INSTRUCTIONS FOR CONTINUING AIRWORTHINESS, AUDIO SYSTEM..............................................E
Appendix F RTCA DO160D Environmental Qualification Form................................ F
Rev Date Change
1 3/25/04 1st Release
2 5/5/04 Clarify/correct installation kit, added note regarding the screw lengths.
3 5/13/04 Change connector back shells to 1-piece, made left/right phasing consis-
tent throughout and corrected section 2.4.3.
4 6/11/04 Change front panel pictures and button layout
5 8/23/04 Corrected P/N, text in section 2.4.1
6 11/19/04 Clarified power wiring in section 2.4.3 and figure 2-1
7 3/16/05 Added list of required test equipment in section 2.11
8 5/24/05 Corrected text description for Unswitched 3 & 4, sect 2.4.10
9 6/22/05 Added note to section 2.4.13 for DME on AUX and logic switching
10 7/14/05 Added info on PA Jumper (J4) to section 2.4.12
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PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
Section I GENERAL INFORMATION
1.1 INTRODUCTION
The PMA8000 represents another evolutionary step in cockpit audio control and intercommunications util-
ity. Using our patented IntelliVox® design, this unit eliminates the requirements for intercom squelch ad-
justments. The unit is designed for outstanding ergonomics and visually defined mode annunciation and
selection.
Before installing and/or using this product, please read this manual completely. This will ensure that you
will take full advantage of all the advanced features in the PMA8000.
1.2 SCOPE
This manual provides detailed installation and operation instructions for the PS Engineering PMA8000series of Audio Selector Panel/Intercom Systems. This includes the following units:
Description Part Number
Model
PMA8000 Stereo Audio Selector Panel with Marker Beacon 050-890-0100
Option 1 Same as above with Digital Recorder added 050-890-0200
Where the functions are identical to all units, it will be referred to herein as a PMA8000. Otherwise, the
applicable units will be specified.
1.3 EQUIPMENT DESCRIPTION
The PMA8000-series is a state of the art audio isolation amplifier and audio selector that contains an automatic voice activated (VOX) intercom system. It can switch two transceivers (Com 1, Com 2 ) and six receivers (Nav 1, Nav 2, ADF, DME, MKR and AUX).
A full duplex TEL mode allows the PMA8000 to act as an audio interface between aircraft headphone and
microphones and specific aircraft approved
Warning
PS Engineering is not responsible for unauthorized airborne use of cellular telephones.
There are four unswitched inputs, available for traffic or EGPWS, autopilot disconnect, and/or radar altimeter warning.
Push buttons select the receiver audio source provided to the headphones. A SPR button allows the user to
listen to the receiver(s) selected on the cabin speaker. Except for the unswitched inputs, all speaker audio is
muted during transmit. All Unswitched inputs are always presented to the aircraft speaker.
Push button switches selects one of the communication transceivers for the pilot and copilot position, and
allows radio transmission. In "Split Mode" the PMA8000 has the ability to allow the pilot to transmit on
com 1 while the copilot can transmit on com 2. A fail-safe mode connects the pilot headphone and microphone to COM 1 if power is removed for any reason, or if the power switch is placed in the Off (Fail-safe)
position.
A six-station voice activated (VOX) intercom is included in the PMA8000. This system has PS Engineer-
ing’s patented IntelliVox® circuitry that eliminates manual adjustments. The system contains six separate
VOX mic circuits, and only opens the microphone channel in use.
: Use of non-aviation approved cellular telephone equipment may be prohibited by regulation.
For airborne use, the PMA8000 must be interfaced with an approved system.
(FAA/FCC) cellular telephone equipment.
The intercom system incorporates pilot isolate, all and crew modes, two independent stereo music inputs
with "Soft Mute," and flashing LED indications for transmit indications. Intercom control is through two
concentric front panel volume controls and a pushbutton intercom mode switch. The small volume knob
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PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
controls the intercom level for the pilot and copilot, while the large knob controls the passenger intercom
volume. Intercom squelch is automatic.
A 3-light Marker Beacon receiver is integrated in the PMA8000. This provides the necessary Marker Beacon lights and audio indications necessary for an Instrument Landing System (ILS) approach. A pushbutton labeled MKR allows the pilot select high or low sensitivity as well as test and mute modes.
1.4 APPROVAL BASIS –
TSO Approval.
The PMA8000-series Audio Selector Panels are FAA approved under TSO C50c (Audio Amplifiers) and
TSO C35d (Marker Beacon Receivers).
All systems comply with relevant portions of EUROCAE RTCA MPS WG No. 7/70, DO-143 and (Marker
Beacon Receivers), ED-14C/DO-160C (Environmental Conditions and Test Procedures for Airborne
Equipment), ED12B/DO-178B, Level D (Software Considerations for Airborne Equipment) and ED-
18/DO-214 (Audio Systems Characteristics and Minimum Operational Performance Standards for Aircraft
Audio Systems).
Operation is subject to the following conditions:
This device may not cause harmful interference.
This device must accept any interference received, including interference that may cause undesired operation.
1.5 SPECIFICATIONS
TSO COMPLIANCE
Marker Beacon: C35d, Class A
Audio Selector/Intercom: C50c, Class A
APPLICABLE DOCUMENTS: RTCA/DO-214 RTCA/DO-143 RTCA/DO-160D
RTCA/DO-178B DO-254
ENVIRONMENTAL Qualifications:
Operating Temperature Range: -15º C to 55ºC
Altitude: Up to 50,000 feet in an non-pressurized area
DIMENSIONS: Height: 1.3 in. (3.3 cm) Width: 6.25 in. (16.9 cm)
WEIGHT
PMA8000 Unit
Rack with connectors
POWER REQUIREMENTS (Including Internal Lighting):
Voltage: 11 to 33 VDC
Maximum Current: 2.5 Amp (Externally protected by a 5A pull-type
A1D1CABSMXXXXXXZBABATBXXE2XXX
Depth behind panel 7.15 in. (18.16 cm)
1.34 lb. (0.61 kg)
0.51 lb. (0.24 kg)
breaker)
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Installation and Operator’s Manual
PS Engineering
Audio Selector Specifications
Audio selector panel input impedance:
510 Ω
Input Isolation: -60 dB (min.)
Speaker Muting: -60 dB (min.)
Speaker Output (into 4 Ω) with no clipping
14 VDC:
28 VDC:
3 Watts (min.)
10 Watts (min.)
Receiver Inputs: 9 (Com 1, Com 2, TEL, Nav 1, Nav 2, ADF,
DME, MKR, AUX)
Unswitched Inputs: 4
Transmitter Selections: 4 (Com 1, Com 2, TEL
Com1/2)
Speaker Impedance:
Headphone Impedance:
4 Ω
150 – 1000 Ω
Headphone Output: 38 mW each headset, no clipping <1% THD typi-
cal
Microphone Impedance:
150 - 600 Ω
Intercom Specifications
Intercom Positions: 6 places (with individual IntelliVox® circuits)
Music Inputs: 2, (Independent, Stereo)
Music Muting: >-30 dB "Soft Mute" when Com or intercom active.
Distortion:
Mic Freq. Response, 3 dB: 300 Hz - 6000 Hz
Music Freq. Response, 3 dB: 10 Hz – 26 kHz
MARKER BEACON RECEIVER:
Frequency: 75 MHz Crystal Controlled
Sensitivity:
Low:
High:
Selectivity: -6 dB at ±10 kHz
External Lamp Output: 7.5 (±4 VDC unloaded, at maximum brightness) VDC
MM Sense: Active high (4.5 ± 1.0VDC)
<1% THD @ 38 mW into 150Ω
Capable of: (preset at factory for field application)
1000 µVolts (Hard) (360 to 570 µV soft)
200 µVolts (Hard) (130 to 200 µV soft)
-40 dB at ±120 kHz
positive when active, max. current 125 mA
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PMA8000 Series Audio Selector Panel and Intercom System
PS Engineering
Installation and Operator’s Manual
1.6 EQUIPMENT SUPPLIED
1 ea. of the following units:
Model Description Part Number
PMA8000 PMA8000 Audio Panel with Marker Beacon and Stereo intercom. 050-890-0100
PMA8000 with option 1 Add Internal recorder to PMA8000 050-890-0200
PMA8000 Installation Kit: 250-890-0000
Description Quantity Part
PMA8000 installation rack assembly 1 430-890-0040
PMA8000 Rack back plate 1 430-890-0050
44-pin connector kit 2 120-891-2045Backshell, connector 2 625-025-2465
4 40 X 7/16 screw w/nylon patch 4 475-440-0007
4 40 X 1/4 screw w/lock washer 4 475-440-0004
4-40 Lock Nut 5 475-013-0001
Solder Lug 1 475-009-0001
Cable Clamp 1 625-001-0002
#6-32 x ½” Flat head Philips screw 6 475-632-0012
#6-32 Clip Nut 6 475-630-0002
Number
1.7 EQUIPMENT REQUIRED BUT NOT SUPPLIED
a. Circuit Breaker: 1 ea; 5 amp PULL TYPE REQUIRED for PMA8000
a) Speaker, 4 Ω
b) Headphone Jacks (Stereo, as Required)
c) Microphone Jacks (as Required)
d) Headphones, 150 Ω (Stereo), up to 6 as required
e) Microphones, up to 6 as required
f) Marker Antenna (75 MHz, VSWR <1:1.5, and appropriate for the airspeed)
g) Interconnect Wiring
1.8 LICENSE REQUIREMENTS
None
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PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
Section II - Installation
2.1 GENERAL INFORMATION
2.1.1 SCOPE
This section provides detailed installation and interconnection instructions for the PS Engineering
PMA8000-Series Audio Selector Panel/Intercom/ with internal Marker Beacon.
Please read this manual carefully before beginning any installation to prevent damage and post-installation
problems. Installation of this equipment requires special tools and knowledge.
2.1.2 Certification Requirements
NOTE
The PMA8000 requires specialized knowledge and tools for an effective installation. An
appropriately rated Certified Aircraft Repair Station must install this equipment in ac-
cordance with applicable regulations. PS Engineering, Incorporated warranty is not valid
unless the equipment is installed by an authorized PS Engineering, Incorporated dealer.
Failure to follow any of the installation instructions, or installation by a non-certified in-
dividual or agency will void the warranty, and may result in an unairworthy installation.
2.2 Unpacking and Preliminary Inspection
Use care when unpacking the equipment. Inspect the units and parts supplied for visible signs of shipping
damage. Examine the unit for loose or broken buttons, bent knobs, etc. Verify the correct quantity of components supplied with the list in Section 1.6 (B). If any claim is to be made, save the shipping material and
contact the freight carrier. Do NOT return units damaged in shipping to PS Engineering. If the unit or accessories show any sign of external shipping damage, contact PS Engineering to arrange for a replacement.
Under no circumstances attempt to install a damaged unit in an aircraft. Equipment returned to PS Engineering for any other reason should be shipped in the original PS Engineering packaging, or other UPS
approved packaging.
2.3 Equipment Installation Procedures
2.3.1 Cooling Requirements
Forced air-cooling of the PMA8000 is not required. However, the units should be kept away from heat
producing sources (i.e. defrost or heater ducts, dropping resistors, heat producing avionics) without adequate cooling air provided.
2.3.2 Mounting Requirements
The PMA8000 must be rigidly mounted to the instrument panel of the aircraft structure and within view
and reach of the pilot position(s). Installation must comply with FAA Advisory Circular AC 43.13-2A. The
unit may be mounted in any area where adequate clearance for the unit and associated wiring bundle exist.
Avoid installing the unit close to high current devices or systems with high-voltage pulse type outputs,
such as DME or transponders. Avoid running the interconnecting bundles near any high current wires.
2.3.3 Audio Panel Mounting Rack Installation
Remove the unit from the mounting tray by unscrewing the 3/32" hex-head screw that is in the center of
the unit. Use caution to avoid hitting the photo-detector lens. Carefully slide the unit free of the tray. Set
the unit aside in a safe location until needed. Install the tray using six clip nuts (475-630-0002), and six
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PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
FHP 6-32 x ½" screws (475-632-0012). The audio selector panel must be supported at front and rear of the
mounting tray.
2.3.4 Audio Panel Tray and Connector Assembly
The rack connectors mate with two 44-pin connectors in the PMA8000. The connectors are a sub miniature
crimp-type, and require the use a hand crimp tool, from table below (or equiv.). The connectors are
mounted to the tray back plate with #4-40 screws (475-440-0007), from the inside of the tray. Ensure that
proper strain relief and chafing precautions are made during wiring and installation, using the cable clamp
(625-001-0002).
Manufacturer Crimping Tool Positioner Extraction tool
AMP 601966-1 601966-6 91067-1
Daniels AFM8 K42 M24308-1
ITT-Cannon 995-0001-584 995-0001-739 91067-1
Table 1 Connector Pin crimping tools
2.4 Cable Harness Wiring
Referring to the appropriate Appendix, assemble a wiring harness as required for the installation. All wires
must be MIL-SPEC in accordance with current regulations. Two- and three-conductor shielded wire must
be used where indicated, and be MIL-C-27500 or equivalent specification. Proper stripping, shielding and
soldering technique must be used at all times. It is imperative that correct wire be used.
Refer to FAA Advisory Circular 43.13-2A for more information. Failure to use correct techniques may
result in improper operation, electrical noise or unit failure. Damage caused by improper installation will
void the PS Engineering warranty.
2.4.1 Noise
Due to the variety and the high power of radio equipment often found in today's general aviation aircraft,
there is a potential for both radiated and conducted noise interference.
The PMA8000 power supply is specifically designed to reduce conducted electrical noise on the aircraft
power bus by at least 50dB. Although this is a large amount of attenuation, it may not eliminate all noise,
particularly if the amplitude of noise is very high. There must be at least 13.8 VDC present at the connector, J2 pins 8 & 9, of the PMA8000 for the power supply to work in its designed regulation. Otherwise, it
cannot adequately attenuate power line noise. Shielding can reduce or prevent radiated noise (i.e., beacon,
electric gyros, switching power supplies, etc.) However, installation combinations can occur where interference is possible. The PMA8000 was designed in a RFI hardened chassis and has internal Electromagnetic Interference (EMI) filters on all inputs and outputs.
Ground loop noise occurs when there are two or more ground paths for the same signal (i.e., airframe and
ground return wire). Large cyclic loads such as strobes, inverters, etc., can inject noise signals onto the
airframe that are detected by the audio system. Follow the wiring diagram very carefully to help ensure a
minimum of ground loop potential. Use only Mil Spec shielded wires (MIL-C-275000, or better). Under no
circumstances combine a microphone and headphone wiring into the same shielded bundle. Always use a
2- or 3-conductor, shield wire as shown on the installation-wiring diagram.
The shields can be daisy-chained together, and then connected to a ground lug mounted on the corner of
the back plate.
Radiated signals can be a factor when low level microphone signals are "bundled" with current carrying
power wires. Keep these cables physically separated. It is very important that you use insulated washers to
isolate the ground return path from the airframe to all headphone and microphone jacks.
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PMA8000 Series Audio Selector Panel and Intercom System
Installation and Operator’s Manual
PS Engineering
NOTE:
Adding a high-performance audio control system, particularly in conjunction with high-performance active
noise canceling headsets, cannot improve on older avionics that were designed for cabin-speaker use. PS
Engineering makes no claim that the audio panel will provide a noise-free audio quality under all installation conditions, particularly with older avionics.
2.4.2 Existing GMA340 Installation
If the installation replaces a GMA340, no changes are required except to incorporate the new capabilities
of the PMA8000.
2.4.3 Power
The PMA8000-Series are compatible with both 14 and 28 Volt DC systems. A five (5) Amp circuit breaker
is required for all installations. Power and ground wires should be #22 connected to J2 Pins 8 and 9. Connect airframe ground to J2 Pin 10 and 11 only. No dropping resistors are required.
2.4.4 Communications Push-to-Talk
An important part of the installation is the PTT (Push-To-Talk) switches that allow the use of your aircraft
communications radio for transmissions. There are three typical configurations that can be used. Select the
case that best fits the installation. Only the person who presses their PTT switch will be heard over the radio. If the pilot and copilot both use the PTT, the only pilot position has access to the radio. The pilot position will have PTT control regardless of the mic selector switch or copilot PTT when the PMA8000 is in
OFF/EMG mode.
the
CASE I: PTT is built into both pilot and copilot yokes.
CASE II: PTT is in pilot yoke only. This configuration requires a modified external PTT switch plugged
into the copilot's microphone jack. (See Appendix A). When the copilot's PTT is pressed, the intercom
switches the microphone audio from pilot to copilot mic.
CASE III: No built in PTT. This requires two built in PTTs to be installed, or modified external PTT
switches to be used. Modify external PTT as required. See Appendix A.
2.4.5 Audio Panel interface
The PMA8000 is designed to interface with standard aircraft avionics, and presents a 500Ω receiver im-
pedance. For best results, a twisted-shielded cable is recommended from the avionics audio source to the
audio panel, with the shield grounded at the audio panel end.
Some avionics do not provide a separate audio low, and may introduce additional electrical noise into the
system. For best results, connect the audio low from the audio panel to the radio ground, using one conductor of the twisted-shielded cable.
2.4.5.1 Speaker Load
The PMA8000 contains one speaker amplifier. Some units with internal speaker amplifiers, such as the
King Radio KX170-series, require a resistive load to prevent damage if their speaker amplifier is not used.
Connect the speaker output from the unit to the COM 2 Speaker load input on the PMA8000 ( J1 27 WRT
28). The speaker load is 16 Ω, 3W.
2.4.6 TEL (Duplex) Function for Cell Phones
This mode is designed to operate with telecommunications systems, such as the AirCell Guardian 1000.
Audio streams selected by the intercom mode are provided to the Tel output, and audio from Tel is presented to the headset. This allows a telephone-like audio interface.
The TEL mode in the PMA8000 is also compatible with many cellular telephones with hands-free headset
interfaces. A 1/8” or 3/32” jack can be installed on the aircraft panel, and interfaces with the PMA8000 as
shown: A patch cord (3/32” to 3/32”) is available from PS Engineering under P/N 425-006-7026.
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