PS Engineering PAC24 Pilot’s Guide

9800 Martel Road

Lenoir City, TN 37772

, 0503

Pilot’s Guide

and

Operation Manual

FAA Approved TSO C50c

JAA-Approved JTSO C50c

Revision 4 202-240-0002 April 2009

Patent No 5,903,227 and 6,160,496

Audio Selector Panel

with Intercom System

Flying Never

PS Engineering, Inc. 2009 ©

Copyrighted information in this manual is subject to change without notice. PS Engineering
reserves the right to improve or change the products or contents of this manual, without
notification of any person or agency. The contents of this pilot’s guide may be downloaded,
stored and reprinted for personal use provided that this copyright information is included.
Commercial use is strictly prohibited. For further information contact the Publications Man­ager at PS Engineering, Inc., 9800 Martel Road, Lenoir City, TN 37772. Phone (865) 988­9800

Sounded So Good!®

Copyright Notice

Revision 4, April 2009 Page 1 PAC24-Series Pilot Guide

This Pilot Guide provides detailed operating instructions for
the PS Engineering PAC24-series, High Performance Audio
Selector Panel/Intercom Systems. Please read it carefully be­fore using the equipment so that you can take full advantage of
its capabilities.

This document is divided into three sections covering the basic
operating areas of the PAC24 systems. They are transceiver
selection, audio selector, and intercom.

1

4

2 3 5

PAC24 Controls

1) Receiver Source Selection

2) Transmitter Selection

3) Volume / Power Controls

4) Speaker Selector

5) Intercom Mode Selector

Power Switch (3) (EMG-Fail Safe Operation)

Unit power is turned on and off by pushing the center (pilot) volume
knob. The power switch controls the audio selector panel functions
and intercom.

Single Panel Fail Safe Operation

In the OFF or "EMG" position, the pilot is connected directly to Com

1. This allows communication capability regardless of unit condi­tion. Any time power is removed or turned
will be placed in the fail-safe mode.

Page 2 PAC24-Series Pilot Guide

OFF, the audio selector

Dual Panel Fail Safe Operation

e

t

In a dual installation, the PAC24 designated as Pilot’s at installation,
will default to Com 1. The audio panel designated as copilot will not
operate in the off position. This prevents compromising the pilot’s au­dio capability in the event of a dual audio panel problem.

Microphone Selector (2)

There are 10 pushbuttons associated with the communications trans­ceivers. The lower buttons control which transceiver is selected for
transmit.

Receiv

Transmi

The PAC24 gives priority to the pilot’s PTT. If the copi­lot it transmitting, and the pilot presses his PTT, the pi­lot’s microphone will be heard over the selected trans­mitter.

The PAC24 has an automatic selector mode. Audio from
the transceiver selected by the Xmit button is automati­cally heard in the headsets and speaker (if selected). You
can check this function by switching from C
C

OM 2 and watch the selected audio light on the selector

OM 1 to

change from COM 1 to COM 2. This ensures the pilot
will always hear the audio from the transceiver he is
transmitting on.

When switching from C

OM 1 to COM 2, while COM 2

audio had been selected, Com 1 audio will continue to be
heard. This eliminates the pilot having to switch Com 1
audio back on, if desired.

When switching from C

OM 1 to COM 2 while Com 2 has

NOT been selected, Com 1 audio will be switched off. In
essence, switching the mic selector will not effect the selection of Com
receiver audio. This is true of all transmitter selections.

When the duplex, or TELEPHONE mode is implemented, Com 5 be­comes the “TEL” position. In a single installation, the intercom mode

Revision 4, April 2009 Page 3 PAC24-Series Pilot Guide

select switch determines who is on the phone:

ISO - pilot,
CREW - pilot and copilot,
ALL - pilot, copilot, passengers

In a standard dual installation, the pilot and copilot can select TEL
mode independently by pressing their respective COM 5 button. The
passengers are on the phone only
and his switch is in the ALL position. The copilot cannot put the pas­sengers on the phone, and the passengers can only get on the phone
when the pilot is on the phone.

In an observer dual installation, the crew box works like a single instal­lation. The observer is treated like a passenger, so he would be on the
phone line when COM5X is selected and the intercom switch is in ALL
mode. The observer cannot select telephone mode independently.

when the pilot has selected TEL mode

Stuck Microphone Protection

The PAC24 has a function designed to prevent unintentional radio
transmissions and blocked frequencies. After 35 seconds of continuous
PTT on any input, the PTT line is lifted, and will remain unkeyed until
the PTT input is recycled.

NOTE: Selecting the COM 5 –TEL– mode will disable pilot and copilot
intercom, as the intercom circuit is transferred to the telephone use. In
crew or ISO mode, selecting TEL mode removes the passengers access
to the telephone.

Swap Mode (Remote transfer of com transceivers)

With a yoke mounted, normally open, momentary switch, the pilot can
change from the current Com transceiver another by depressing this
switch. Activating the swap switch will select the next transceiver, cy­cling from 1 to 2 to 3 etc.

Observer transmit selection (part number –040X).

If the installation uses a dual panel, observer configuration, the crew
panel serves the pilot and copilot, while the second audio panel serves
the observer.

The pilot and copilot have access to all transceivers. The observer can
access any radio that the crew does not have selected for transmit. If the
crew selects a radio for transmit that the observer has previously se­lected, all parties can transmit, but the pilot, copilot, have priority over
the observer (in that order). If the observer selects a different radio, and
then attempts to re-select a radio in use by the crew, the observer will

Page 4 PAC24-Series Pilot Guide