Revision 7 Feb. 2008 Page 1 200-118-0005
9800 Martel Road
Lenoir City, TN 37772
(865) 988-9800 FAX (865) 988-6619
www.ps-engineering.com
PM501
PM501
Low Cost 4-Place
Panel Mounted Intercom
Operator's and Installation Manual
NOTICE
: In certified aircraft, warranty is
not valid unless this product is installed by an
Authorized PS Engineering dealer.
Document Number 200-118-0005
Revision 7, February 2008
Sound Quality. Sound Engineering.
PM501 Operation/Installation Manual Page 2 Revision 7, Feb 2008
Introduction
Congratulations on your purchase of a
PM501 intercom! We at PS Engineering wel-
come you to our family.
The PM501 is a panel mounted, 4-place
intercom that offers an intelligent low cost alter-
native for budget minded pilots who still want
quality sound and performance. This manual
provides information on the installation and
operation of the PM501. Please read it com-
pletely before installation to reduce the risk of
damage to the unit and maximize your enjoy-
ment of its use.
Description
The PM501 is a 4-place, panel-mount inter-
com with individual output amplifiers for the
pilot, copilot, and passengers 1 & 2. The VOX
(Voice Activated Squelch) circuit prevents mic
audio from getting through the intercom until
someone speaks and automatically opens the
circuit. The volume control adjusts the level for
all headsets and functions as a PUSH-ON/
PUSH-OFF power switch.
The PM501 has an automatic, fail-safe con-
nection to the aircraft radio. In the event that
power to the intercom is lost, an internal relay
will immediately connect the pilot's headset
directly to the aircraft radio.
A provision for an entertainment input al-
lows the pilot and passengers to listen to music
during flight. During intercom activity, this mu-
sic automatically mutes to allow communica-
tions without distraction. Note: the music is NOT
muted during radio reception.
The 2-position switch acts as a mode selec-
tor. In the down position, the intercom is in the
ALL mode. Each position will hear the aircraft
radio, music, and each other. In the up position,
(ISO mode) only the pilot is connected to the air-
craft radio for undisturbed radio communications.
In ISO, the pilot is no longer on the intercom. All
others will continue to communicate with each
other and listen to music if desired.
With the PM501, both the pilot and copilot
have radio transmit capabilities. Only the person
who presses their Push To Talk (PTT) will be
heard over the aircraft radio. If both pilot and
copilot press the PTT, the copilot will override.
The pilot regains priority by switching the unit
off.
Specifications
Input power: 12-28 Volts DC
Current Drain: < 70 mA Externally fused at 1 Amp
Headphone Impedance: 150-
1000
Ω
Typical
Total audio power available: 225 mW
Audio Distortion: <10% @ 75 mW into 150
Ω
load
Aircraft Radio Impedance: 1000
Ω
Typical
±3 dB Mic Frequency Response: 350 Hz-6000 Hz
±3 dB Music Frequency Response: 200 Hz - 15 kHz
Net weight: 8.5 Ounces (.340 kg)
Dimensions: 0.90" H X 2.60" W X 4.85" D
(2.2 cm x 6.6 cm x 12.3 cm)
FAA Approval – NONE
It is the installer’s responsibility to deter-
mine the necessary approvals required.
Note
: Installation of the PM501, using supplied hardware
and available wiring does not require special tools or knowl-
edge other than described in Advisory Circular 43.13-2. How-
ever, it is the installer's responsibility to determine the approval
basis for this installation. PS Engineering makes no assertions
that this unit is FAA-approved for all certified aircraft. An FAA
Form 337 or other approval may be required.