trig TY96, Installation Manual

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TY96/96A and TY97/97A VHF Radio Installation Manual 26 September 2018
01238-00 Issue AJ
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Trig Avionics Limited Page 17
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Circlip washer (p/n 00242-00).
The Circlip washer should be fitted with a set of Circlip pliers.
5.6 Interface Details
5.6.1 Speaker Output
The speaker output can drive a 4 ohm or greater cabin speaker. The speaker should be rated at 4 watts
or higher.
5.6.2 Headphone Outputs
The TY96 can drive two sets of headphones. The output is stereo and is intended for headsets of 150 to
600 ohm impedance.
The radio also works correctly when a mono headset is plugged into a stereo socket, or can be wired for
mono headphones sockets.
5.6.3 Mono Audio Output
This output is used to drive a conventional 600 ohm audio panel input. Note that only the received
radio audio and transmitter sidetone will be output; music and aux audio will NOT be present.
5.6.4 Transmit Interlock
When two VHF radios are mounted in an aircraft the transmit interlock input of one can be connected
to the transmit PTT key of the other radio. When the other radio transmitter is keyed, the squelch
threshold of this radio is increased to minimise break-through between one radio and the other.
Note: To improve the performance when using two radios, the antennas should be as far
apart as practical – for example on the top and bottom of the fuselage.
5.6.5 Lighting Bus Input
The TY96 will adjust the brightness of the front panel switch lighting according to the voltage on the
lighting bus input. The lighting bus voltage is automatically adapted to the aircraft bus voltage.
If no lighting bus input is detected, the radio will automatically control the front panel lighting based on
the ambient light sensor.
5.6.6 PTT1/2 Key Input
Two Push to Talk (PTT) inputs are provided, which correspond to the two microphone inputs. Only
the corresponding microphone input is routed to the transmitter when the key switch is pressed.
The PTT1 input has priority over the PTT2 input – if the PTT1 switch is closed when the PTT2 switch
is closed, the input from Microphone 1 is routed to the transmitter.
The inputs are active low, and will be asserted when the voltage to ground is pulled below
approximately 4 volts. The input should be connected to a momentary switch on the yoke or on the
microphone.
For retrofit installations where a single PTT input is shared for both microphone inputs, Single PTT
mode can be enabled. See section 6.2.14 for more details.
5.6.7 Intercom Key Input
The intercom key switch input allows the intercom function to be selected using a remote switch, or
permanently enabled by grounding the pin inside the connector. The input is active low, and will be
asserted when the voltage to ground is pulled below approximately 4 volts.
If this pin is tied low, the intercom function depends on the vox operated squelch.
Note: It is possible to combine both the key switch and the vox activation, or to use only one.