PS Engineering PM3000 11931A, PM3000 11932, PM3000 11933A, PM3000 11934 Operation And Installation Manual

9800 Martel Road

Lenoir City, TN 37772

PM3000

High-fidelity Stereo Intercom System

Part Number 11931A: 4-Place

and

Part Number 11932: 6-Place with

Operation and Installation Manual

FAA-TSO

C50c

Also includes 11933A, 11934, non-FAA TSO units

Document P/N 200-193-0005
Revision 8, Nov. 2013

PS Engineering, Inc. 2013 ©

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 [phone]

Standard

Standard

CREW Mode

CREW

200-193-0005 Rev. 8, Nov. 2013

Page 1

Section I General Information

1.1 Introduction

The PM3000 is an FAA-TSO approved, panel

mounted, 4- to 6-place high-fidelity stereo intercom
system (ICS). Please read this manual completely
before installation to minimize the risk of damage to
the unit and to become familiar with all the features.

1.2 Scope

This manual contains installation and operational in­structions for the following PS Engineering units:

Model Description Part Number

PM3000 Standard 4-place system 11931A

PM3000 6-place system w/CREW 11932

PM3000 4-place w/recorder 11933A

PM3000 6-place w/CREW & recorder 11934

1.3 Description

The PM3000 is a 4- or 6-place (depending on model),
panel-mounted intercom with multiple volume and
VOX (voice activated squelch) circuits using unified
volume and squelch controls for the pilot, and copilot.
Passengers volume is adjusted at the headset, after
setting a master volume service adjustment on the side
of the unit.

With few controls for the pilot to use, the operation of
the PM3000 is very straightforward. Yet the unit out­performs its much more complicated competition. Al­though there is only one volume control knob, when an
adjustment is made to the volume control, the crew
output amplifiers are being changed simultaneously.
Likewise, when the squelch control knob is adjusted,
several VOX circuits are being changed at the same
time. Since the system is designed to use modern ste­reo headsets, it is not necessary to balance the volume
and squelch controls at the intercom.

A mode switch allows the pilot to select different con-

figurations. The "ALL" mode places all headsets on a
party line. In the "ISO" mode, the pilot is isolated

from all others and is connected to the aircraft radio
allowing un-interrupted radio communications.

The third mode, "CREW," included in part number

11932 (and 11934), allows the pilot and copilot to be
separated from the passengers.

The PM3000 has an automatic fail-safe interconnect to
the aircraft radios. If power is disrupted to the inter­com for any reason, the pilot's headset is connected
directly to the aircraft radio allowing continued radio
communications in one earcup.

A 2-color LED is green when power is on and changes
to red when a Push to Talk (PTT or microphone key)
is pressed.

Provision for entertainment input allows the pilot, co­pilot and passengers the option to listen to music dur­ing flight. During intercom or aircraft radio reception,
this music will automatically mute to allow communi­cations without distraction. When the activity ceases,

the SoftMute™ circuit gradually returns the music to

the original listening volume. By depressing the
“Mute” control (located on the Squelch knob) once, it
is possible to have the music remain at a constant
level, regardless of any ICS or radio traffic.

During various phases of flight, the degree of impor­tance of the aircraft radio will vary. Because the "ISO"
mode connects the pilot directly to the aircraft radio,
select the "ISO" mode when the pilot must have top
priority on radio transmissions.

Both pilot and copilot have transmit capabilities over
the radio. The PM3000 only allows the voice of the
person who presses their PTT to be transmitted over
the aircraft radio. If both pilot and copilot press the
PTT at the same time, the copilot will override. When
either pilot or co-pilot presses PTT, all other micro­phones are disabled. The pilot can regain priority by
switching the unit off.

1.4 Approval Basis

The PM3000, part number 11931A or 11932, is FAA-

approved under TSO-C50c, and RTCA, Inc. DO-214.
Due to the fact that there is no TSO for the recorder
function in the 11933A and 11934, these units are not
TSO-approved. It is the responsibility of the installer
to determine the approval basis for these units.

1.5 Specifications

Input power: 13.8 - 27.5 Volts DC
Current : < 200 mA (Externally fused at 1 Amp)
Headphone Impedance: 150-1000 Ω (typical)
Audio Distortion: <1.2% @ 50mW into 150 Ω load
Aircraft Radio Impedance: 1000 Ω (typical)
Mic Frequency Response:±3 dB, 350 Hz — 6000 Hz
Music Frequency Response: ±3 dB, 200 Hz – 15 kHz
Unit weight: 12 Ounces (0.34 kg)
Dimensions:

1.25" H x 3.00" W x 5.50" D
(3.2 x 7.6 x 14.0 cm)
Environmental and technical qualifications:
RTCA DO-160C/DO-214
Temperature -20º to +55º C

Page 2

200-193-0005 Rev. 8, Nov. 2013

1.6 Equipment required but not sup-

plied

1.200

0.838 0.838

1.200

A.Interconnecting cables as required (may be ordered

from PS Engineering)

B.Headphones, 150 Ω stereo, as required

C.Microphones, general aviation, as required

D.Interconnect wiring

E.Circuit Breaker 1 Amp.

F.

Optional (see page 8):

2 ¼” Mounting Plate without
2 ¼” Mounting Plate with crew p/n 575-030-0005

crew p/n 575-030-0007

1.7 License Requirements

None

Section II Installation

2.1 General Information

The PM3000 comes with all mounting hardware and
jacks for installation. Installation of the PM3000, us-

ing the hardware supplied and available wiring does
not require special tools or knowledge other than de­scribed in FAA Advisory Circular 43.13-2B. It is the
installer's responsibility to determine the approval ba­sis for this installation. An FAA Form 337, or other
approval may be required. See Appendix B for exam­ple of FAA Form 337.

2.2 Unpacking and preliminary inspec­tion

The PM3000 was carefully inspected mechanically

and thoroughly tested electronically before shipment.
It should be free of electrical or cosmetic defect.

Upon receipt, verify that the parts kit includes the fol­lowing:

PM3000 Installation Kits:

Part Number Description 11931A 11932 11933A 11934

475-442-0002 #4-40 screws, black 2 2 2 2
625-003-0001 Knobs (Soft Touch) 2 2 2 2
575-030-0001 Faceplate (w/crew) 1 1
575-030-0003 Faceplate (no crew) 1 1
425-025-0010 25 pin connector shell 1 1 1 1
425-020-5090 Crimp Sockets 25 25 25 25
625-025-0001 Connector hood 1 1 1 1
475-002-0002 Connector Thumbscrews 1 1 1 1
200-193-0003 Operator's Guide 1 1 1 1
122-001-0000 Drill Template 1 1 1 1
475-003-0002 Insulated Shoulder Washers 9 13 9 13
475-003-0001 Insulated Flat Washers 9 13 9 13
550-001-0002 Stereo Headphone Jack 4 6 4 6
550-001-0003 Microphone Jack 4 6 4 6
550-008-0001 Music Input Jack ⅛” 1 2 1 2
550-005-0001 Playback Plug 3.3mm 1 1

0.250

0.325

2 ea. 0.125

NOT TO SCALE

0.297

2 ea. 0.314

2.3 Equipment installation proce­dures

Figure 1 Hole Spacing

1. Using the template, drill six holes in the instrument
panel in a location convenient to the pilot position
(s).

2. Insert the PM3000 from behind the instrument

panel, aligning the holes for the knobs, LED, and
switch.

3. Place the aluminum plate over the knob shafts and
secure, using the two # 4-40 round head screws pro­vided.

4. Install the knobs over the volume and squelch con­trol shafts.

5. Complete a wiring harness in accordance with Ap­pendix D.

2.4 Cable harness wiring

To complete the installation, a wire harness must be
made as shown in Appendix D.

Note:

PS Engineering can make a custom-tailored wir­ing harness for the installer. All harnesses use
Mil-spec quality components with professional
techniques, and are fully tested before shipment.
Contact PS Engineering for more information,
www.ps-engineering.com.

If the aircraft already has pilot headset jacks installed,
you may re-use one mono set for the AUX (radio )
jacks but they should be moved to a new location to
avoid confusion with the pilot's headphone jacks. In
the event the intercom has to be removed for any rea­son, these jacks provide access to the aircraft radio
system. Remove and discard copilot headset jacks if
these are monaural.

To connect intercom into the aircraft audio system,
parallel the appropriate set of cables from the intercom
to the Auxiliary Aircraft Radio Headset Jacks. Finally,
install new pilot, copilot and passenger headset jacks

200-193-0005 Rev. 8, Nov. 2013

Page 3

into the aircraft and connect them directly to the ap-

propriate pins of the PM3000. See the wiring diagram

for all details of the wire harness interconnect.

2.4.1 Electrical Noise Issues

WARNING: You must use individual shielded cables

for the microphone and headphone jacks. Combining
these two wires WILL cause loud oscillations and de­grade the intercom function. The oscillation is caused
by the cross-coupling between the large headphone
signal and the small microphone signal. The resulting
feedback is a high-pitched squeal that varies with the
volume control.

Due to the variety of the radio equipment found in
today's general aviation aircraft, there is the potential
for both radiated and conducted noise interference.

The PM3000 has a specially designed power supply to

reduce conducted electrical noise on the power bus of
the aircraft by at least 50dB. Although this is a very
large amount of attenuation, it does not eliminate all
noise when the amount is excessive. There must be at

least 13.75 Volts DC present at the PM3000 for the

power supply to work within its optimum regulation.
Otherwise, it will not be able to attenuate noise prop­erly.

Shielding can protect the system from radiated noise
(rotating beacon, electric gyros, switching power sup­plies, etc.). However, installation combinations can
occur where minor interference is possible. The

PM3000 was designed in an interference -protected

chassis and has internal filter capacitors on all input
lines.

Ground loop noise occurs when there are two different
return paths for the same signal, such as airframe and
ground return wire. Large cyclic loads such as strobes,
inverters, etc., can inject audible signals onto the air­frame return path. Follow the wiring diagram very
carefully to help insure a minimum of ground loop
potential. Radiated signals can be a factor when low
level microphone signals are bundled with current car­rying power wires. Keep these cables separated.

Insulating washers are required
headphone jacks to isolate them from aircraft ground.
The use of a conductor instead of a shield for ground
return eliminates these ground loop paths.

on all microphone and

2.4.2 Power & Dimmer

The PM3000 was designed to work with 12.8 to 27.5
volt DC negative ground systems. The PM3000 must

be externally protected with a one ampere (1A) circuit
breaker or fuse.

[11931A & 11933A] Connect Pin 5 to the aircraft

dimmer bus. This will adjust the Power/Xmit LED for

varying lighting conditions. If no connection is made,
the LED will be at maximum brightness.

The unit is shipped for 14 VDC dimmer systems. For a
28 VDC aircraft dimmer system, open the PM3000
case and remove the Jumper J2.

2.4.3 Unswitched Audio Input

The PM3000, P/N 11931A & 11933A have two
unswitched audio inputs available for 500Ω aviation
audio sources. Pin 17 is Unswitched #1, and is also
provided to the pilot in Fail-Safe Mode. Unswitched
#2 input is Pin 4.

2.4.4 Sidetone

The PM3000 can be modified to produce sidetone
(hearing your voice during transmit), if the aircraft
radios do not produce it. Contact the PS Engineering
factory for details.

2.4.5 Entertainment Input

Stereo entertainment devices can be connected to the

PM3000. Install ⅛" stereo jacks convenient the pilot

and passengers to connect the entertainment devices
into the system. PM3000, part number 11931A has a
single entertainment input. The part number 11932
will accommodate two inputs, one for the crew, and
another separate input that feeds the 4 passengers in
CREW mode.

It is possible to use only one entertainment device to

Use only low level output of the entertainment devices

to connect to the PM3000. Maximum signal level on

the input is 2-volts peak-to-peak.

DO NOT USE

OUTPUT LEVELS.

This will cause internal damage.

provide music for both inputs in the 11932 system by
connecting the output of the entertainment device in
parallel to both the Music #1 and Music #2 inputs. We
highly recommend, however, that you install a switch
between the entertainment device and Music #1. This
will give the pilot and copilot the ability to switch off
music while in the CREW mode.

The music device will automatically mute when the
ICS or aircraft radio becomes active. The Soft Mute™
feature slowly returns the music to full volume when
the activity ceases. Pressing the Mute disable switch

If speaker levels are to be used, install an

Audio Link, p/n 101PL2,

available from Crutchfield (1-800-955-3000).

SPEAKER

Page 4

200-193-0005 Rev. 8, Nov. 2013