PS Engineering
PMA5000EX Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-550-0100
Page 3-1
Rev. 3, Dec. 2015
Section III OPERATION
3.1 SCOPE
This section provides detailed operating instructions for the PS Engineering PMA5000EX, Audio Selector
Panel/Intercom Systems. Please read it carefully before using the equipment so that you can take full ad-
vantage of its capabilities.
This section is divided into sections covering the basic operating areas of the PMA5000EX systems. They
are Communications Transceiver Selection, Audio Selector, Intercom special functions.
Figure 3-1 PMA5000EX Operating Controls
3.2 Power on-off EMG (1)
Unit power is turned on and off by pushing the volume knob. In the
OFF
or "
EMG
" position, the pilot head-
set is connected directly to Com 1 as well as unswitched input #1. This allows communication capability
regardless of unit condition. Any time power is removed or turned
OFF
, the audio selector will revert to fail-
safe mode.
The power switch controls all audio selector panel functions, and intercom. All pushbutton selections and
function modes will be remembered and return to the last state when turned on.
3.3 Communications Transmit (XMT) Selection (2)
There are two pushbuttons associated with the communications transceiver selection. The two lower but-
tons (# 2) control which transceiver is selected for transmit. The top row of pushbuttons (# 3) allows selec-
tion of the receiver audio. Push the lower button to select the desired COM transmitter.
The PMA5000EX-Series has an automatic selector system. Audio from the selected transceiver is automat-
ically heard in the headsets. You can check this function by switching from C
OM
1 transmitter to Com 2
transmitter by pressing the C
OM
2 transmitter selector pushbutton. See that the associated Com 2 receive
pushbutton indicator light that is located immediately above the Com 2 transmitter pushbutton turns green.
This guarantees that the pilot will
always
hear the audio from the transceiver selected for transmit.
The PMA5000EX “remembers” the receiver selection, so that when switching transmitters from C
OM
1 to
C
OM
2, if C
OM
2 audio was previously selected, C
OM
1 audio will continue to be heard. This eliminates the
pilot having to switch Com 1 audio back on, after changing transmitters.
When switching from C
OM
1 to C
OM
2 while Com 2 was not previously selected, C
OM
1 audio will be
switched off. In essence, switching the mic selector will not override prior selection of COM receiver au-