PS Engineering
PMA5000EX Audio Selector Panel and Intercom System
Installation and Operator’s Manual
200-550-0100
Page 2-4
Rev. 3, Dec. 2015
Figure 2-1 Cellular telephone interface for rear connector, if an additional jack is desired
2.4.5.1 Cell phone Sidetone
As shipped from PS Engineering, the PMA5000EX does NOT provide cellular telephone sidetone (the us-
er’s voice fed back to the headset). Some cell phones do not provide sidetone. In PMA5000EX, telephone
sidetone can be enabled by holding the TEL button for more than one second. This setting will be remem-
bered when the power is off.
NOTE
Unauthorized use of unapproved cellular telephone devices in aircraft is subject to FCC enforcement ac-
tion, which may include a $10,000 fine per incident. PS Engineering, Inc. does not endorse using unap-
proved cellular telephone equipment in flight, and takes no responsibility for the user’s action.
PS Engineering does not guarantee compatibility with personal cellular telephones. For a list of phones that
have been tested, visit www.ps-engineering.com.
2.4.6
Transmit Interlock
Some communications transceivers use a transmit-interlock system. To fully utilize the Split Mode feature,
this function must be disabled. Consult that manufacturer's installation manual.
2.4.7
"Swap" Mode
When a momentary, normally open, push-button switch is connected between pin 20 on the J2 connector
and aircraft ground (or J2-pin 21), the user can switch between Com 1 and 2 by depressing this switch
without having to turn the mic selector switch. This yoke-mounted switch eliminates the need to remove
your hands from the yoke to change transceivers. The transfer of TX indication from Com 1 to Com 2
shows that the swap has been initiated; there is no dedicated swap indicator.
2.4.8
Backlighting
The PMA5000EX has an automatic dimming of the pushbutton annunciation LEDs controlled by a photo-
cell. Control of the unit white text backlighting is through the aircraft avionics dimmer For 14 V aircraft,
connect J2 Pins 6 and 7 to the aircraft dimmer bus, and pin 5 to ground. For 28-volt systems, connect pin 7
to the aircraft dimmer, and pins 5 and 6 to ground.
If an external dimmer control is
not
used, a constant back light illumination can be established for
nighttime viewing. Pin 6 or 7 (depending on system voltage) must be tied to power (J2, pin 8 or 9) for the
back lighting system to work. The photocell mounted in the unit face will automatically adjust the intensity
of the push-button annunciator LEDs.
2.4.9
Unswitched inputs
J1, pins 31, 29 and J2 pin 15 are unswitched, unmuted (by transmitter keying), inputs # 1, 3 and 4, respec-
tively. These inputs are presented to the pilot and copilot regardless of the audio configuration, and will
always mute the entertainment inputs. These 510Ω inputs can be used for altimeter DH audio, GPS way-
point audio, autopilot disconnect tones, or any other critical audio signal. Unswitched #1 is always present-
ed to the to the crew headphones, and is available to the pilot in fail-safe (off) mode. Unswitched 3 and 4
inputs are always presented to the crew headphones.
Unswitched
Input
Hear in
Fail Safe
Hear in
Crew Headset
Gain
1
Yes
Yes
1:1(fixed)
2
No
Yes
1:1(fixed)
3
No
Yes
Adjustable
4
No
Yes
1:1(fixed)
5 (jack)
No
Yes
1:1(fixed)
Table 2-2 Unswitched input table
Unswitched #2, J1 pin 44 is unswitched is always connected to the Pilot’s headphone.