Installation manual

PS Engineering
PMA6000 Series Audio Selector Panel and Intercom System
Installation Manual
200-066-0006 Page 2-4 Rev. 6, March 2005
the single entertainment device and entertainment input #1. This will allow the pilot and copilot to decide if
they hear entertainment while in the Crew mode.
Local oscillators and internal signals from some entertainment 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 entertainment devices.
NOTE: Use the low level
output of any entertainment device to connect to the
audio panel. Maximum signal level is 2 VAC p-p. DO NOT use a speaker-
level output, this will cause internal damage in the audio panel.
To use a line level, install an AudioLink PowerLink 101PL2 adapter, available
from Crutchfield at 1-800-955-3000
(804)-817-1000, [e-mail]
2.4.2.4 Soft Mute (Stereo only)
Entertainment #1 input has a "Soft Mute" inhibit switch that is part of the volume control located on the
front panel. By pressing it once, the entertainment device will not be muted, push it again and it will be
muted by intercom and radio conversation.
On PMA6000 stereo units with serial numbers above “G” series on the intercom board (second set of serial
numbers) have an Entertainment #2 Karoake mode capability. This "Soft Mute" inhibit switch is part of the
squelch control located on the front panel. By pressing it once, the entertainment device will not be muted,
push it again and it will be muted by intercom and radio conversation.
2.4.3 External 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 ra-
dio. If the pilot and copilot both use the PTT, the copilot position has access to the radio. The pilot posi-
tion will have PTT control regardless of the copilot when the PMA6000 is in the F
AIL-SAFE 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 mic 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).
2.4.4 Transmit Interlock
Some communications transceivers use a transmit interlock system. In order to fully utilize the Split Mode
feature, this function must be disabled. Consult that manufacturer's installation manual.
2.4.5 Power
The PMA6000-Series are compatible with both 13.8 and 28 Volt DC systems. A two (2) Amp circuit
breaker is required. Power and ground wires must be a twisted #18 AWG pair.
Included with this product is a power dropping resistor to be connected in series with the power input, bot-
tom connector, pin 20. This dropping resistor is supplied for 28 volt systems so that unnecessary heat dis-
sipation inside the PMA6000 can be avoided.