Apr/2006 - Honeywell KHF 1050 System Installation Manual

When asserted (grounded), bit 18 of message (Output label 037), word ID #1
"Other side keyed" is set to 0.
The OTHER SIDE PTT and the KEY EVENT discrete inputs/outputs function as
an "interlock" to ensure that both systems can not transmit at the same time.
Such an interlock function is required when two HF systems share a common
antenna on an aircraft.
Example: If the co-pilot is transmitting (or tuning the antenna) on the right-side
HF system, the pilot will not be able to key the left-side system until the
right-side system returns to the receive mode. Once the right-side system has
returned to receive mode, the pilot will be able to immediately transmit (or tune
the antenna) on the left-side system.
5.F.(6) Other Side On
(J10531-49)
This input line is part of the dual system interface and is continuously read.
When pulled to +12 Volts by the CR COM line of the opposite system, the first
system is set to operate as part of a dual system. The result is that the receiving
action always utilizes the bridging amplifier in the KAC 1052.
When this input line is allowed to float to ground, the system performs as a
single system, typically bypassing the bridging amplifier and receiving through
the tuned matching network. This input exists on Receiver/Exciters with
hardware modification 1 installed and is active in software levels of
RXEXSW0105 or higher.
6. Equipment Installation
6.A Electrical Bonding Connections
6.A.(1) Antenna Coupler Electrical Bonding Connections
The importance of properly bonding the KAC 1052 Antenna Coupler to the
airframe can not be over emphasized.
Good RF bonding of the KAC 1052 Antenna Coupler to aircraft metal structure
is essential in achieving maximum efficiency from the system and minimizing
interference with other systems in the aircraft.
The primary electrical bonding path is through a ground strap from a ground
post on the KAC 1052 to a point on the airframe near the antenna feed point.
More than one ground strap can be used. Additional grounding is achieved via
Revison 2
N
KHF 1050 SYSTEM INSTALLATION MANUAL
23-10-09
Page 2039

Apr/2006