Bendix/King
KMA28
Audio Amplifier/Intercom/Marker Beacon Receiver
006-10565-0000
Page 2-8
Rev. 0, Sept. 2000
connected to pin W of the J3 connector. On the AirCell interface diagram these are listed
as data/fax lines, but they are used for voice interface in this case.
Use a 2-conductor with shield cable, and connect the shield to Pin M of the J3.
If interface is desired with another type of wireless telecommunications unit, the aircraft
owner can purchase an after-market interface cable. By Federal Communications Com-
mission (FCC) regulations, these can only be used on the ground in the United States.
Unauthorized use of cellular telephone devices in aircraft is subject to FCC enforcement action,
which may include a $10,000 fine per incident. Honeywell, Inc. does not endorse using unapproved
cellular telephone equipment in flight, and takes no responsibility for the user’s action.
2.8.1 Hook
Switches
While the mic selector acts as the hook switch for the pilot, additional hook switches
must be installed to have full access to the cellphone system. The copilot hook switch is a
SPST switch that connects pin L of J2 on the KMA 28 to ground to place the copilot on
the cellphone.
KMA 28 J2, pin M is the passenger hook switch. Install a SPST switch in a location adja-
cent to each passenger headset where cellphone use is desired. When pin M is connected
to ground through any switch, the passenger microphones are all on the cellphone system.
The wireless communication “tel” system utilizes an intercom loop. Therefore, any time
the cellphone is in use from the pilot or copilot side, pilot and copilot will lose intercom
capability. In the ALL mode, when the passengers’ activate the cell phone, the pilots will
have intercom, and continue to hear and transmit over the avionics normally. However
the passengers will not have intercom, because they are on the telephone.
To prevent unwanted distractions, only the pilot and copilot will hear an incoming call
ring signal. They can then decide to allow a passenger to activate the hook switch and use
the telephone.
If the pilot has selected “TEL” mode, the passengers cannot access the telephone in the
“CREW” intercom mode, but they will hear the call.
