PS Engineering PMA450B Series User guide

9800 Martel Road
Lenoir City, TN 37772
www.ps-engineering.com
PMA450B
Document P/N 200-450-0600
Revision 5, August 2020
Audio Selector Panel with Marker Beacon Receiver
High-fidelity Stereo Intercom, USB Charging Port
Bluetooth® Connectivity, flightmate®
System Installation and Operation Manual
FAA- TSO C139a, C35d, C71
Patented under one or more of the following;
No. 4,941,187; 5,903,227; 6,160,496 and 6,493,450, 7,391,877
PS Engineering, Inc. 2020 ©
Copyright Notice
Any reproduction or retransmittal of this publication, or any portion thereof, without the expressed written permission of PS En-
gineering, Inc. is strictly prohibited. For further information, contact the Publications Manager at PS Engineering, Inc., 9800
Martel Road, Lenoir City, TN 37772. Phone [phone], email [e-mail].
In certified aircraft, warranty is not valid unless this product is installed by an
Authorized PS Engineering dealer.

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
1.1.1 LIMITATIONS.....................................................................................................................1-2
1.5 SPECIFICATIONS.................................................................................................................................................................1-3
1.6 EQUIPMENT SUPPLIED......................................................................................................................................................1-4
1.8 LICENSE REQUIREMENTS................................................................................................................................................1-5
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............................................................. 2-2
2.3.4 AUDIO PANEL TRAY AND CONNECTOR ASSEMBLY .........................................................2-2
2.4 CABLE HARNESS WIRING........................................................................................................................................................2-2
2.4.1 ELECTRICAL NOISE...........................................................................................................2-2
2.4.2 EXISTING GMA340 AND PMA8000 INSTALLATIONS ......................................................2-3
2.4.3 POWER ..............................................................................................................................2-4
2.4.4 COMMUNICATIONS PUSH-TO-TALK..................................................................................2-4
2.4.5 AUDIO PANEL INTERFACE ................................................................................................ 2-4
2.4.6 TRANSMIT INTERLOCK .....................................................................................................2-4
2.4.7 BACKLIGHTING.................................................................................................................2-4
2.4.8 UNSWITCHED INPUTS........................................................................................................2-5
2.4.9 "SWAP"MODE ..................................................................................................................2-5
2.4.10 PUBLIC ADDRESS MODE.................................................................................................2-5
2.4.11 WIRED TELEPHONE/SATELLITE COMMUNICATION INPUT..............................................2-6
2.4.12 MUSIC INPUTS.................................................................................................................2-6
2.4.13 PLAYBACK BUTTON INSTALLATION (J2 PIN 22).............................................................2-6
2.5 MARKER BEACON INSTALLATION (050-450-0601, -0602 ONLY)...........................................................................................2-7
2.5.1 MARKER ANTENNA INSTALLATION .................................................................................2-7
2.5.2 EXTERNAL MARKER LIGHTS............................................................................................2-7
2.5.3 MIDDLE MARKER SENSE..................................................................................................2-7
2.6 FLIGHTMATE®.........................................................................................................................................................................2-8
2.6.1 MESSAGE TRIGGERS:........................................................................................................2-8
2.6.2 STORING MESSAGES:........................................................................................................2-9
2.7 USER SETUP ADJUSTMENTS ..................................................................................................................................................2-10
2.7.1 ADJUST SCREEN..............................................................................................................2-10
2.7.2 RENAME “SWITCHED”INPUTS........................................................................................ 2-11
2.7.3 VOLUME SETUP ..............................................................................................................2-11
2.7.4 INTELLIAUDIO LOCATION SETUP................................................................................... 2-12
2.7.5 BLUETOOTH®MENU ......................................................................................................2-12
2.7.6 BLUETOOTH #2(P/N 050-450-0601 &-0701 ONLY) ......................................................2-13
2.8 COMMUNICATIONS ANTENNA INSTALLATION NOTES .........................................................................................................2-13
2.9 PMA450B PIN ASSIGNMENTS................................................................................................................................................2-14
2.10 WIRING CHECKOUT ..............................................................................................................................................................2-15
2.11 UNIT INSTALLATION..............................................................................................................................................................2-15
2.12 OPERATIONAL CHECKOUT....................................................................................................................................................2-15
2.12.1 REQUIRED TEST EQUIPMENT........................................................................................2-15
2.12.2 AUDIO PANEL TEST ......................................................................................................2-15
2.12.3 MARKER CHECKOUT (050-450--0601 ONLY)...............................................................2-16
2.12.4 BLUETOOTH CHECKOUT...............................................................................................2-16

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page ii Rev. 5, August 2020
2.12.5 INTERNAL RECORDER CHECKOUT................................................................................2-16
2.13 FINAL INSPECTION.................................................................................................................................................................2-16
Section III OPERATION............................................3-1
3.1 SCOPE.....................................................................................................................................................................................3-1
3.2 POWER AND FAIL SAFE (1)......................................................................................................................................................3-1
3.3 DISPLAY MENU SELECTION (6)...............................................................................................................................................3-1
3.4 COMMUNICATIONS TRANSMIT (XMT) SELECTION (2)..........................................................................................................3-2
3.4.1 SPLIT MODE......................................................................................................................3-2
3.5 COM AUDIO SELECTOR (3) ....................................................................................................................................................3-2
3.5.1 SWAP MODE (SWITCH FROM COM 1TO COM 2REMOTELY)............................................ 3-3
3.5.2 INTELLIAUDIO®DIMENSIONAL AUDIO ...........................................................................3-3
3.5.3 COM MONITOR MODE ......................................................................................................3-3
3.5.4 NAVAID SELECTION (4)....................................................................................................3-3
3.6 SPEAKER AMPLIFIER (7) .........................................................................................................................................................3-4
3.6.1 PUBLIC ADDRESS FUNCTION............................................................................................ 3-4
3.7 MARKER BEACON OPERATION (9) (PART NUMBER 050-450-0601, -0701ONLY)...................................................................3-5
3.7.1 MARKER BEACON SENSITIVITY........................................................................................3-5
3.8 INTERCOM OPERATION (8)......................................................................................................................................................3-5
3.8.1 INTELLIVOX®INTERCOM VOX-SQUELCH........................................................................3-5
3.8.2 INTERCOM VOLUME CONTROL (1)...................................................................................3-6
3.8.3 INTERCOM MODES (8) ......................................................................................................3-6
3.10 MUSIC CONTROL,DISTRIBUTION AND MUTING...................................................................................................................3-10
3.10.1 MUSIC MUTING ............................................................................................................3-11
3.10.2 MUSIC VOLUME............................................................................................................3-12
3.10.3 MUSIC IN PILOT ISO MODE...........................................................................................3-12
3.11 BLUETOOTH®CONNECTION .................................................................................................................................................3-12
3.11.1 PAIRING AND UN-PAIRING BLUETOOTH DEVICES.........................................................3-13
3.12 BLUETOOTH®TELEPHONE MODE........................................................................................................................................3-13
3.12.1 BLUETOOTH RESET.......................................................................................................3-14
3.12.2 BLUETOOTH PIN...........................................................................................................3-14
3.12.3 BLUETOOTH CELLULAR TELEPHONE SIDETONE ...........................................................3-15
3.13 WIRED SATCOM/CELL PHONE INPUT ...................................................................................................................................3-15
3.14 INTERNAL RECORDER AND PLAYBACK.................................................................................................................................3-15
3.15 PS STREAMER OPERATION (P/N 050-450-0601 &-0701 ONLY)..........................................................................................3-16
3.15.1 PAIRING ........................................................................................................................3-16
3.15.2 STREAMER ON/OFF........................................................................................................3-17
3.15.3 SOURCE SELECTION...................................................................................................... 3-17
3.16 TIMER FUNCTIONS...................................................................................................................................................................3-1
3.16.1 SETTING THE TIMER........................................................................................................3-1
3.16.2 COUNT DOWN.................................................................................................................3-1
3.16.3 COUNT UP ....................................................................................................................... 3-1
3.17 USER SETUP MENUS.................................................................................................................................................................3-1
3.17.1 ADJUST SCREEN (OLED ADJUSTMENT).........................................................................3-2
3.17.2 RENAME “SWITCHED”INPUTS........................................................................................ 3-2
3.17.3 OPTIONS..........................................................................................................................3-3
3.17.4 INTELLIAUDIO LOCATION SETUP................................................................................... 3-4
3.18 BLUETOOTH SETUP..................................................................................................................................................................3-4
3.18.2 BLUETOOTH 1(BT1), BLUETOOTH 2(BT2 AVAILABLE IN -0601 &-0701 ONLY)AND
STREAMER SETUP.........................................................................................................................3-4
3.18.3 VOLUME SETUP ..............................................................................................................3-6
3.18.4 FLIGHTMATE SETUP........................................................................................................3-7
3.19 USB CHARGING PORT (10)......................................................................................................................................................3-8
Section IV –Warranty and Service....................................4-1
4.1 WARRANTY..............................................................................................................................................................................4-1
4.2 FACTORY SERVICE ..................................................................................................................................................................4-1
Appendix A –PMA450B Installation Drawings.....................................................................A
Appendix B –J1 Connector Interconnect ...........................................................................B
Appendix C –J2 Connector Interconnect ...........................................................................C

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page iii Rev. 5, August 2020
Appendix D –Instructions for FAA Form 337 and continuing airworthiness....................D
8.1 INSTRUCTIONS FOR FAA FORM 337, AUDIO PANELS............................................................................................................... D
8.2 INSTRUCTIONS FOR CONTINUING AIRWORTHINESS,AUDIO SYSTEM ..................................................................................... D
Appendix E –RTCA DO160G Environmental Qualification Form........................E
Rev
Date
Change
New
April 2018
Release of manual for PMA450B
1
June 2018
Revise menu order
2
May 2019
Added specific GoPro device compatibility in §3.15
3
December 2019
Add flightmate® notes
4
May 2020
Added “S” indicator for switched navaid selection indication §3.5.4 (s/n T45B2103 and up)
5
August 2020
Changed connector hoods

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 1-1 Rev. 5, August 2020
Section I – GENERAL INFORMATION
1.1 INTRODUCTION
The PMA450B represents a revolutionary step in cockpit audio control and intercommunications utility. In-
telliAudio®, using the USAF patented technology, provides True Dimensional Sound, which helps pilots to
easily discern simultaneous radio receptions. Our patented IntelliVox® design, front panel USB power jack,
and pilot programmable configurations, marks this panel as the next level of audio control. The unit is de-
signed 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 PMA450B.
1.2 SCOPE
This manual provides detailed installation and operation instructions for the PS Engineering PMA450B-
series of Audio Selector Panel/Intercom Systems. This includes the following units:
Model
Part Number
Marker
Receiver
flightmate®
BT 2/PS
Streamer
PMA450B
050-450-0601
YES
YES
YES
PMA450B
050-450-0602
YES
YES
NO
PMA450B
050-450-0701
NO
YES
YES
PMA450B
050-450-0702
NO
YES
NO
1.3 EQUIPMENT DESCRIPTION
The PMA450B is a state-of-the-art audio isolation amplifier and audio selector that contains an automatic
voice activated (VOX) intercom system and integral marker beacon receiver. It can switch two transceivers
(Com 1, Com 2) and six receivers (Nav 1, Nav 2, MKR, and three additional inputs that can be individually
labeled, for use with ADF, DME AUX, etc.).
Warning: Use ofnon-aviation approved cellular telephone equipmentmaybe prohibitedby FCC regulation.
PS Engineering is not responsible for unauthorized airborne use of cellular telephones.
For airborne use, the PMA450B must be interfaced with an approved system.
There are four unswitched inputs, available for traffic or EGPWS, autopilot disconnect, and/or radar altimeter
warning.
Pushbuttons 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. Unswitched inputs 1& 2 are always presented to the aircraft speaker. Unswitched
input 3 & 4 will be presented to the speaker when the front panel SPR push button has been selected.
Pushbutton switches select one of the communication transceivers for the pilot and copilot position, and allow
radio transmission. In "Split Mode”, the PMA450B 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.
Unswitched input #1 is also provided to the pilot headphone (left side headset ear cup) in fail-safe
A six-station voice activated (VOX) intercom is included in the PMA450B. This system has PS Engineering’s
patented IntelliVox® circuitry that eliminates manual adjustments. The intercom system incorporates pilot
isolate, all and crew modes, two independent stereo music inputs with "SoftMute™". Intercom volume con-
trol is through two concentric front panel knobs and a pushbutton intercom mode switch. The small volume

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 1-2 Rev. 5, August 2020
knob controls the intercom level for the pilot and copilot, while the large knob controls the passenger inter-
com volume. Intercom squelch is automatic.
PMA450B part numbers 050-450-0601 and -0602 contain a 75 MHz Marker Beacon receiver and 3-light
indicator. This provides the necessary Marker Beacon lights and audio indications necessary for that portion
of an Instrument Landing System (ILS) approach. A pushbutton labeled MKR allows the pilot select audio
on as well as test and mute modes. Marker high sensitivity is also controlled by this button.
The front panel USB-type connector is available for charging devices, such as iPad or cell phones. Up to 15
Watts and 3.5 Amps are available. This connector does NOT provide any data interface.
In the PMA450B, a Bluetooth® wireless interface is available for wireless telephone and music connection.
Our newest innovation is flightmate®, a tool that can improve flight safety and reduce workload. flightmate
allows the user to store four audio messages that can be trigged by cockpit signals when connected for safety
alerts.
APPROVAL BASIS
FAA TSO Approval
The PMA450B-series Audio Selector Panels are FAA approved under TSO C139A (Audio Amplifiers) TSO
C35d (Marker Beacon Receivers) and C71 (DC Power Supplies)
All systems comply with relevant portions of EUROCAE RTCA MPS WG No. 7/70, DO-143 and (Marker
Beacon Receivers), ED-14C/DO-160G (Environmental Conditions and Test Procedures for Airborne Equip-
ment), ED12B/DO-178B, Level D (Software Considerations for Airborne Equipment) and ED- 18/DO-214A
(Audio Systems Characteristics and Minimum Operational Performance Standards for Aircraft Audio Sys-
tems).
1.4.1 Limitations
This article meets the minimum performance and quality control standards required by a technical standard
order (TSO). Installation of this article requires separate approval.
Refer to Advisory Circular 20-41A for information on TSO installation approval.
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.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 1-3 Rev. 5, August 2020
1.5 SPECIFICATIONS
TSO COMPLIANCE
Marker Beacon:
FAA TSO C35d, Class A
Audio Selector/Intercom:
FAA TSO C139a, Class 1a
DC Charging Jack
FAA TSO C71
APPLICABLE DOCUMENTS:
RTCA/DO-214A RTCA/DO-143 RTCA/DO-160G
RTCA/DO-178C, DO-254
ENVIRONMENTAL Qualifications:
A1D1CABSMXXXXXXZBABATBXXE2XXX
Operating Temperature Range:
-15º C to 55ºC
Altitude:
Up to 35,000 feet in a non-pressurized area
DIMENSIONS:
Height: 1.3 in. (3.3 cm) Width: 6.25 in. (15.9 cm)
Depth behind panel 7.15 in. (18.16 cm)
WEIGHT
PMA450B Unit
Rack with connectors
1.34 lb. (0.61 kg)
0.51 lb. (0.24 kg)
POWER REQUIREMENTS (Including Internal Lighting):
Voltage:
11 to 33 VDC
Maximum Current:
3.5 Amp (Externally protected by a 5A pull-type breaker)
Audio Selector Specifications
Audio selector panel input impedance:
510 
Input Isolation:
-60 dB (min.)
Speaker Muting:
-60 dB (min.)
Speaker Output (into 4 ) with no clipping
14 VDC:
28 VDC:
3 Watts (min.)
10 Watts (min.)
Receiver Inputs:
7 (Com 1, Com 2, Nav 1, Nav 2, 2 ea. Additional switched
inputs available for ADF, DME, etc.)
Unswitched Inputs:
4 (Two switched inputs can be converted to unswitched, if
desired, during installation.)
Transmitter Selections:
3 (Com 1, Com 2, Com1/2)
Speaker Impedance:
4 
Headphone Impedance:
150 –1000 
Headphone Output:
30 mW each headset, no clipping <.5% THD typical
Microphone Impedance:
150 - 600 
Bluetooth® Radio
Class 3, FCC ID QOQWT32AE or QOQWT32I
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:
<1% THD @ 30 mW into 150
Mic Freq. Response, 3 dB:
300 Hz - 6000 Hz
Music Freq. Response, 3 dB:
10 Hz –26 kHz

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 1-4 Rev. 5, August 2020
MARKER BEACON RECEIVER (-0601, -0602 only)
Frequency:
75 MHz Crystal Controlled
Sensitivity:
Low:
High:
Capable of: (preset at factory for field application)
1000 Volts (Hard) (360 to 570 V soft)
200 Volts (Hard) (130 to 200 V soft)
Selectivity:
-6 dB at ±10 kHz
-40 dB at ±120 kHz
External Lamp Output:
7.5 (±4 VDC unloaded, at maximum brightness) VDC posi-
tive when active, max. current 125 mA
MM Sense:
Active high (4.5 ± 1.0VDC)
USB Charging Port
Available Current
3.5A (15W Maximum) output, short circuit and over-current
protected
Voltage
5 VDC
1.6 EQUIPMENT SUPPLIED
One each of the following units:
Model
Description
Part Number
PMA450B
Digital Stereo Audio Selector Panel with Marker Beacon, USB Charg-
ing port, PS Streamer function and flightmate®
050-450-0601
PMA450B
Digital Stereo Audio Selector Panel with Marker Beacon, USB Charg-
ing port, and flightmate® (No PS Streamer)
050-450-0602
PMA450B
Digital Stereo Audio Selector Panel, with USB Charging port, PS
Streamer function and flightmate®, without Marker Beacon
050-450-0701
PMA450B
Digital Stereo Audio Selector Panel, USB Charging port, and flight-
mate® (No PS Streamer or Marker Beacon)
050-450-0702
PMA450 Installation Kit: 250-890-0000
Description
Quantity
Part
Number
Installation rack assembly
1
430-890-0040
Rack back plate
1
430-890-0050
44-pin connector kit
2
120-891-2045-
Back shell, bottom
2
625-025-1131
Back shell cover
2
625-025-1132
2-56 X 3/16 screw for connector shell
4
475-256-0516
4 40 X 7/16 screw w/nylon patch
4
475-440-0007
4 40 X 3/8 screw w/nylon patch
4
475-440-1038
4-40 x ¼” screw with lock washer
2
475-440-0001
Solder Lug
2
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
EQUIPMENT REQUIRED BUT NOT SUPPLIED
a. Circuit Breaker: 1 ea.; 5 amp PULL TYPE REQUIRED for PMA450B
b. Speaker, 4 as desired
c. Headphone Jacks (Stereo, as Required)
d. Microphone Jacks (as Required)
e. Headphones, 150 (Stereo), up to 6 as required
f. Microphones, up to 6 as required
g. Marker Antenna (75 MHz, VSWR <1:1.5, and appropriate for the airspeed) (-0601, -0602 Only)
h. Interconnect Wiring

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 1-5 Rev. 5, August 2020
1.8 LICENSE REQUIREMENTS
None
PMA450B Bluetooth™ Radio approval:
•FCC ID: QOQWT32AE or QOQWT32I
•Industry Canada ID: 5123A-BGTWT32AE, or 5123-BGTWT32I
•CE EMC Directive 89/336/EEC as amended by Directives 92/31/EEC and 93/68/EEC
NOTE
Unauthorized use of unapproved cellular telephone devices in aircraft is subject to FCC enforcement ac-
tion, which may include a $10,000 fine per incident.
FCC Regulation 47 CFR § 22.925 Prohibition on airborne operation of cellular telephones.
Cellular telephones installed in or carried aboard airplanes, balloons or any other type of aircraft must not
be operated while such aircraft are airborne (not touching the ground). When any aircraft leaves the ground,
all cellular telephones on board that aircraft must be turned off.
PS Engineering, Inc. does not endorse using unapproved cellular telephone equipment in flight, and takes
no responsibility for the user’s action.
PS Engineering does not guarantee compatibility with personal cellular telephones.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-1 Rev. 5, August 2020
Section II - INSTALLATION
GENERAL INFORMATION
2.1.1 SCOPE
This section provides detailed installation and interconnection instructions for the PS Engineering PMA450B
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, test equipment (refer to §2.12.1) and installer knowledge
as required by 14 CFR 65.81 (b).
2.1.2 Certification Requirements NOTE
The PMA450B requires specialized knowledge and tools for an effective installation. An appropriately
rated Certified Aircraft Repair Station must install this equipment in accordance with applicable regula-
tions. 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 individual or agency
will void the warranty, and may result in an unairworthy installation.
This article meets the minimum performance and quality control standards required by a technical standard
order (TSO). Installation of this article requires separate approval. Refer to AC 20-41A for information
regarding Substitute TSO Aircraft Equipment.
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 com-
ponents supplied with the list in §1.6. 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 cir-
cumstances 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.
Equipment Installation Procedures
2.3.1 Cooling Requirements
Forced air-cooling of the PMA450B is not required. However, the units should be kept away from heat pro-
ducing sources (i.e. defrost or heater ducts, dropping resistors, heat producing avionics) without adequate
cooling air provided.
2.3.2 Mounting Requirements
The PMA450B must be rigidly mounted to the instrument panel of the aircraft structure, within view and
reach of the pilot position(s). Installation must comply with FAA Advisory Circular AC 43.13-2B, or other
FAA-approved aircraft technical data. The unit may be mounted in any area where adequate clearance for
the unit and associated wiring bundle exist.
To prevent noise, 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.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-2 Rev. 5, August 2020
2.3.3 Audio Panel Mounting Rack Installation
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 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 PMA450B. 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 (475-440-1038), from the inside of the tray. The connector back
shell is two pieces, (625-025-1131 and cover 625-025-1132) held together by 4 #2-56 screws (475-256-0516).
This allows the back shell to be installed after the connector is populated.
Ensure that proper strain relief and chafing precautions are made during wiring and installation, using the
cable clamp (625-001-0002).
Two grounding lugs are provided, which may be attached to the rear mounting plate with 2 ea. #4-40 x ¼”
screws with captivated lock washers. These provide a convenient location to connect the shield ground ter-
minations.
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 2-1 Connector Pin crimping tools
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 sol-
dering technique must be used at all times. It is imperative that correct wire be used.
Refer to FAA Advisory Circular 43.13-2B 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 Electrical 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 PMA450B 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 PMA450B 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 PMA450B was designed in an RFI hardened chassis and has internal Electromagnetic Inter-
ference (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 air-
frame that are detected by the audio system. Follow the wiring diagram very carefully to help ensure a min-
imum 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 the ground lugs mounted on the back plate
shown in Appendix B.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-3 Rev. 5, August 2020
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.
2.4.1.1 Music Inputs and Noise
PMA450B units utilize a wired differential input to help prevent noise from entering the music system. This
feature is usually transparent to the installer; however, it is important that the appropriate music signal and
ground connections are made directly to the dedicated music signal and ground inputs on the PMA450B. The
power for IFE and audio panel should be a common bus.
If a music jack instead of a music source is installed for Music 1 or 2, we recommend grounding the jack to
airframe ground.
NOISE 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 and PMA8000 Installations
If the installation replaces a GMA340 or any of the PMA8000 series, no changes are necessary as long as the
existing installation meets the requirements. All existing functions of the GMA340 as afforded by the
PMA450B will become instantly available. However, if the previous installation had three COMs, the
PMA450B will not support the third COM; the PMA450B handles only two COM transceivers. The
PMA8000C, P/N 050-890-0303 will support three COMs, call your local PS Engineering dealer for more
information.
2.4.2.1 Differences with GMA340 connector
Connector
Pin
GMA340 Function
PMA450B Function
J1
3
COM 3
TEL Audio Hi
J1
4
COM 3
TEL Lo
J1
5
COM 3
TEL Mic Audio Hi
J1
6
COM 3
No Connection
J1
16
MASQ Inhibit
No Connection
J1
23
COM 3 Speaker Load
AUX Audio Input
J1
24
COM 3 Speaker Load
No Connection
J1
25
COM Speaker Load
No Connection
J1
26
COM Speaker Load
No Connection
J1
27
COM Speaker Load
No Connection
J1
28
COM Speaker Load
No Connection
J1
29
No Connection
Unswitched #3
J2
15
High Music Gain Select
Unswitched #4
J2
17
8Ω Speaker Select
No Connection
J2
18
No Connection
Aux Enable Output
J2
19
Tone Enable
PA Enable
J2
29
Failsafe warn
No Connection
J2
30
Com TX Mute
No Connection
Table 2-2 GMA340–PMA450B connector differences
Installations where the external marker outputs are connected to a Sandel 3308 Navigation Display will re-
quire additional loading resistors. Refer to the Sandel installation data for more information.

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PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-4 Rev. 5, August 2020
2.4.3 Power
The PMA450B is 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 #22AWG connect power to J2 Pins 8 and 9.
Connect airframe ground to J2 Pin 10 and 11 only.
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 PMA450B is in the
OFF/EMG mode.
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 PMA450B is designed to interface with standard aircraft avionics, and presents a 510 receiver imped-
ance. 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 PMA450B contains a speaker amplifier. The PMA450B does not contain any resistive speaker loads.
Some older aviation radios units with internal speaker amplifiers, require a resistive load if their speaker
amplifier is not used. If needed, connect the radio speaker output from the transceiver to a 16, 3W resistor
in the harness.
2.4.5.2 Installation with Monaural Headsets
Not recommended, because the benefit of IntelliAudio is lost. However, if desired, the PMA450B can be
installed monaurally by using the LEFT audio connections only (left side contains Fail-Safe audio). Do NOT
short left and right together.
NOTE: Mono headsets that short the tip and ring (i.e. older models) may introduce audio distortion
when used. Modern, stereo headsets are recommended in all positions.
2.4.6 Transmit Interlock
Some communications transceivers use a transmit-interlock system. To utilize the Split Mode feature, this
function must be disabled. Consult the radio manufacturer's installation manual.
2.4.7 Backlighting
The PMA450B has an automatic dimming of the pushbutton annunciation LEDs and marker lamps controlled
by a photocell. Control of the unit nomenclature backlighting is through the aircraft avionics dimmer. For 14
V aircraft, connect J2 Pins 6 and 7 to the aircraft dimmer bus, and pin 5 to ground. For 28-volt systems,
connect pin 7 to the aircraft dimmer, and pins 5 and 6 to ground.
If an external dimmer control is not used, a constant back light illumination can be established for nighttime
viewing. Pin 6 or 7 (depending on system voltage) must be tied to power (J2, pin 8 or 9) for the back lighting

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-5 Rev. 5, August 2020
system to work. The photocell mounted in the unit face will automatically adjust the intensity of the push-
button annunciator LEDs.
2.4.8 Unswitched inputs
J1, pins 31 (Unsw 1), 44 (Unsw 2) 29 (Unsw 3) and J2 pin 15 (Unsw 4) are unswitched, unmuted (by trans-
mitter keying), inputs.
These inputs are presented to the pilot and copilot regardless of the audio configuration, and will always mute
the crew entertainment inputs. These 510Ω inputs can be used for altimeter DH audio, GPS waypoint audio,
autopilot disconnect tones, or any other critical audio signal.
Unswitched #1 is always presented to the speaker, plus to the crew headphones, and is available to the pilot
in fail-safe (off) mode.
Unswitched 1 & 2 are always presented to the speaker, plus to the crew headphones.
*Unswitched 3 and 4 inputs are always presented to the crew headphones but presented to the aircraft speaker
only when the speaker is selected.
Unswitched
Input
Hear in
Fail Safe
Hear in
Crew Headset
Hear in SPR
Adjustable at installation
1
Yes
Yes
Yes
Yes
2
No
Yes
Yes
Yes
3
No
Yes
When SPR Se-
lected
Yes
4
No
Yes
When SPR Se-
lected
Yes
Table 2-3 Unswitched inputs
The audio low for unswitched #4 (J2, pin 15) should be connected to a convenient audio low. However, this
should NOT be connected to Music Low. NOTE
Inputs 1 and 2 are fixed (1:1), and any audio level adjustments must be made at the input source. Unswitched
#3 and #4 can be adjusted at installation. Refer to Adjustments §2.7.
2.4.8.1 Additional unswitched inputs
If necessary, unused switched inputs (ADF, DME, etc.) can be converted to unswitched inputs. Contact PS
Engineering for more information.
2.4.9 "Swap" Mode
When a momentary, normally open, push-button switch is connected between pin 20 on the J2 connector and
aircraft ground, the user can switch between Com 1 and 2 by depressing this switch without having to turn
the mic selector switch. This yoke-mounted switch eliminates the need to remove your hands from the yoke
to change transceivers. The transfer of TX indication from Com 1 to Com 2 shows that the swap has been
initiated; there is no dedicated swap indicator.
2.4.9.1 Remote ICS mode control
A long press of the remote SWAP switch (>1 second) will change the intercom mode, in order
All/CREW/ISO/All, as shown on the intercom mode indicator on the PMA450B.
2.4.10 Public Address Mode
By holding the N1 pushbutton for more than one (1) seconds, the PMA450B will be placed into public ad-
dress (PA) mode. In this mode, the pilot will be talking over the cockpit speaker when he presses his PTT
switch. Copilot will continue on the selected COM radio. The C1 & C2 Transmit indicates will go off in PA.
The display will include PA & SPR on the right side, and change to PUBLIC ADDRESS when the pilot’s
PTT is pressed.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-6 Rev. 5, August 2020
2.4.10.1 PA Mute (J2, Pin 12)
Pin 12 of J2 is a TTL logic output that is pulled low during PTT operation. This is used to control external
public address or external entertainment systems and prevent feedback during radio transmission.
2.4.11 Wired Telephone/Satellite Communication input
The PMA450B can accommodate a wired cell phone interface on J1 Pins 3, 4 and 5.
Whenever the wired telephone/satellite is active, the telephone configuration will appear on the OLED screen
for dynamic adjustments to volume and sidetone as needed.
Both Bluetooth and wired Telephone and be accommodated, however, only ONE can be active at a time.
See Appendix C and D for intercom connection configurations. It is critical to the proper operation of this
system to have this connector wiring made in accordance with these diagrams. Use 2- and 3-conductor, MIL-
spec cable as shown. Connect the shields at the audio panel end only, and tie to the audio low inputs as shown.
2.4.12 Music Inputs
The PMA450B has four available music inputs. Music input number 1 is J2 pins 23 (left channel) and 24
(right channel), with respect to pin 25, and Music number 2 is connected to 26 (left channel), 27 (right chan-
nel), with respect to 28, plus Bluetooth® modules to stream music from a paired device.
NOTE
Use the low-level output of any additional Music device to connect to the audio panel.
Maximum signal level is 3 VAC p-p. DO NOT use a speaker-level output; this will
cause internal damage in the audio panel.
CAUTION
Local oscillators and internal signals from Music equipment can cause undesired interference with other
aircraft systems. Before takeoff, operate the entertainment devices to determine if there is any adverse effect
within the aircraft systems. If any unusual operation is noted in flight, immediately switch off the entertain-
ment devices.
All additional entertainment devices must be switched off for both takeoff and landing.
2.4.12.1 Passenger Mute (J2 Pin 13 & 14)
Connecting J2 pin 13 to pin 14 (or ground) through a SPST switch places the Passenger music source into
the Karaoke Mode. In this mode, incoming music and intercom conversation will not mute the music for the
passengers’ intercom net. This is useful for passenger-area control of the music muting, and overrides the
PMA450B Music Mute menu-controlled setting.
2.4.13 Playback button Installation (J2 Pin 22)
The pilot and copilot can hear the aircraft radio playback.
The Internal Recorder System can be played back from the front panel by pressing the RCV button of the
radio selected for transmission.
Alternatively, a remote, momentary, normally open (NO) push button switch may be installed if desired to
activate the Recording System playback. This switch can be located anywhere in cockpit convenient to the
pilot's reach. The NO switch should be connected to pin 22 of J2 of the PMA450B, and ground. When in-
stalled, this button will act as in §3.13.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-7 Rev. 5, August 2020
2.4.13.1 Cell phone Sidetone
The PMA450B provides cellular telephone sidetone (the user’s voice fed back to the headset). Some cell
phones provide sidetone, and may have poor audio quality if both sources are combined. The cell phone
sidetone is adjustable in the Bluetooth® operation screen See §2.6.
Marker Beacon Installation (050-450-0601, -0602 Only)
2.5.1 Marker Antenna Installation
A marker beacon antenna, appropriate to the type and speed of the aircraft, is required (not included). Refer
to aircraft and antenna manufacturer's installation instructions, as well as AC43.13-2B (or later revision),
Chapter 3, for information on proper antenna installation techniques. The marker beacon antenna must be
mounted on the bottom of the aircraft.
2.5.2 External Marker Lights
For installations that require external marker beacon lights, there are three outputs that can drive 12-Volt
lamps only. The external output lamps are driven high (typically +7.0 VDC 4.0 VDC unloaded, at MAX
brightness) when active. Maximum source current per lamp is 125 mA. Voltage varies with photocell dim-
ming.
2.5.3 Middle Marker Sense
A Middle Marker Sense output signal is available from the PMA450B to certain flight control systems. This
function will not operate during the test mode. This output will go to +4.5 VDC (1.0 VDC) when a valid
Middle Marker signal is received. This output is J1, pin 39.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-8 Rev. 5, August 2020
flightmate®
The flightmate® is an audio storage system with four audio messages can be triggered by external inputs.
BEFORE USE,FLIGHTMATE MUST BE ENABLED FROM THE INSTALLER SETUP PAGE.
VISIT YOUR AVIONICS SHOP FOR DETAILS OR CONTACT PS ENGINEERING.
2.6.1 Message triggers:
NOTE:
THESE MESSAGES ARE STRICTLY SUPPLEMENTAL AND PILOT OPTION,AND
SHALL NOT REPLACE ANY EXISTING ALERTS IN THE AIRCRAFT.
IT IS THE INSTALLERS’RESPONSIBILITY TO DETERMINE IF THIS ALTERATION
IS MAJOR OR MINOR AND PROVIDE APPROPRIATE DOCUMENTATION (FORM
337, SUPPLEMENTS,ETC.)
Function
Connector pin
Logic
Must be acknowledged
Message Trigger 1
J2-17
Active high (12 to 28 VDC)
No
Message Trigger 2
J2-19
Active Low (ground)
Yes
Message Trigger 3
J2-30
Active Low (ground)
Yes
Message Trigger 4
J1-24
Active Low (ground)
Yes
Message Acknowledge
J1-28
Active Low (ground)
Alert #1 is configured to accept an active high, but shall cease to play when the stimulus is removed. This is
intended for such a system as a stall warning, which clears autonomously, this will NOT stop with the
acknowledgement.
Messages 2, 3, and 4 are stopped with the momentary push of the ACKNOWLEDGE button on the front
panel, or an external Acknowledge button. When J1-28 is grounded through a NO Momentary switch as an
ACK button, the messages will stop playing. If J1-28 is connected to ground permanently, the message will
play once when triggered and then stop.
NOTE: Some GMA340 inputs pins may have been used in previous installations and will have to be repur-
posed or removed if no longer needed.
Since flightmate® has to be configured to be active, the PMA450B will remain plug & play compatible
with the GMA340 and no wiring changes are required.
These are:
Pin
PMA450B
GMA340
J2-17
Message 1 Trigger
8Ω speaker select (installations where an 8Ω speaker is
used)
J2-19
Message 2 Trigger
Tone Enable (Makes tone for button pushes in GMA340)
J2-30
Message 3 Trigger
TX Mute disables receivers in transmit or split
J1-24
Message 4 Trigger
COM 3 Speaker Load
J1-28
Message Acknowledge
COM 2 Speaker Load
.

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PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-9 Rev. 5, August 2020
2.6.2 Storing Messages:
2.6.2.1 Audio Alert Messages
The PMA450B has four discrete messages that can be played when triggered by an external event.
The recording time is limited to 5 seconds per message.
Messages can be changed from the user setup menu.
Message Location
Factory Stored Message
Connector
Input
Logic
Message #1
Chime
J2-17
Active High (5-28
VDC)
Message #2
“Check oil pressure”
J2-19
Active Low
Message #3
“Master caution”
J2-30
Active Low
Message #4
“Check fuel”
J1-24
Active Low
Message Acknowledge
J1-28
Active Low
These four messages will play back when the trigger associated with the message number is activated.
Message 1 will play as long as the trigger is active, but cease when the stimulus is removed, and is suitable
to supplement a Sonalert Piezoelectric buzzer. This cannot be stopped by the front panel or external
Acknowledge button.
NOTE: Message 1 is the only message that is suitable to be used in parallel with a Sonalert.
Message 2 –4 will play when triggered, and stop when the ACK button is pushed, or external Acknowledge
button pushed (J1-28, Active Low).
(Serial T45B2103 and up) Alert Messages 2 through 4 can be configured through the dealer setup function
to play once and stop, or continuously until the condition is removed or ACK pushed. Contact PS Engineering
for more information.
If J1-28 is grounded, then messages 2 –4 will play once and stop.
Messages are played only in the crew headset. They are not heard over the cockpit speaker.
Note1: The external triggers are configured from the factory as shown. They can be reconfigured in the field
to accept Active High or Active Low, or be off completely. Contact PS Engineering for more information.

PS Engineering
PMA450B Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-450-0600 Page 2-10 Rev. 5, August 2020
User Setup Adjustments
**DO NOT MAKE ADJUSTMENTS IN FLIGHT**
Cycling power will remove the audio panel from the user setup menus and back to normal audio panel oper-
ation.
To access the user setup adjustment menus, turn the PMA450B off and then back on. While the version
screen is displayed, push and hold the bottom line-select button (there is an indicator bar in the display indi-
cating that a menu is available).
This places the unit into the “User Configurable Mode – home screen”. This allows adjustment for:
•OLED Screen Adjustment
•Rename Switched Inputs
•Bluetooth menus
•Mute mode recall
Note: in this mode, the audio panel functions will be inoperative
2.7.1 Adjust Screen
The first items are adjustments to the OLED, allowing the installer or user to tailor the backlight intensity to
suit the cockpit conditions, and set the time period before the menus revert to the “home” screen.
2.7.1.1 Brightness
Adjusting the Brightness level requires se-
lecting either of the two line select buttons
and then turning the inner knob. Counter-
clockwise to lower the number (level of
Brightness) and clockwise to increase the
number (level of Brightness).
To change the display:
Press the line select for the desired item.
Turn the small, inner knob to change the
brightness as desired.
OLED will change in real time while adjustments are made.

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200-450-0600 Page 2-11 Rev. 5, August 2020
It will stay in this screen until the menu times out and returns to the adjustment home screen.
2.7.1.2 Display Timeout
This is a feature that allows the end user to adjust how quickly the screen menu timeout (revert to main
menu), factory setting is 8 seconds.
NOTE: A long press (> 1 second) will also back up one menu level.
This allows adjustment of the timeout screen and can be configured from 1 second to 30 seconds when turning
the inner knob.
For a user that is unfamiliar with the product, this will give them enough time to learn the system. After being
familiar then the user can speed up the timeout screen as needed.
It will stay in this screen until the menu times out and returns to the adjustment home screen.
To exit the home screen and return to normal operation, turn the PMA450B off, and back on again.
2.7.2 Rename “Switched” Inputs
The system is factory set to default as ADF, & DME as shown.
The three inputs are from top to bottom:
1. Switched input #1 J1, Pin 7 wrt Pin 8 (Default ADF)
2. Switched input #2 J1, Pin 21 wrt Pin 22 (Default DME)
3. NOTE: In PMA450B --0701 (No Marker) Switched #1, or #2 can be renamed to MKR for a re-
mote audio input.
The customer will have access to rename. Maximum 9 letters per line and A thru a and 0 thru 9 will be
available.
•Press the line select for desired input.
•Turn the large outer knob to select the letter to change. A cursor appears under the active letter po-
sition.
•Turn the small, inner knob to increment or decrement the letter.
•You can select 9 alphanumeric digits.
•To add a blank space:
oBlank spaces can’t be added to the end of a string, but you can add a temporary character
and go back and change it to a space:
oADFA1
oChange extra “A” to space ADF 1
It will stay in this screen until the menu times out and returns to the adjustment home screen.
Cycle PMA450B power to exit the setup screen.
2.7.3 Volume Setup
The volume level of the marker beacon receiver, cockpit speaker, and switched inputs can be adjusted at the
setup menu.
From the Setup menu, press More → More→ Marker, or Speaker, → More, Switched Inputs and
turn the small knob to adjust the volume of the marker beacon, cockpit speaker, and switched (ADF/DME)
volumes. The green volume bar and numerical readout will indicate the receiver volume in this menu. NOTE:
volume cannot be turned completely off. Units without marker receiver will not have a MKR Volume menu.