Which component is used to switch from the ADF antenna to the Comms antenna when radios are keyed?

Which component is used to switch from the ADF antenna to the Comms antenna when radios are keyed?

• A. Antenna switch module
• B. Radio transceiver
• C. Direction finder motor
• D. A-395 Relay Assembly

Answer: (D)

Switching the antenna path is done by a relay that changes connections when the radio is keyed. In this setup, the A-395 Relay Assembly sits in the antenna routing network and, when the radio is keyed for transmission, energizes its relays to connect the Comms antenna and disconnect the ADF antenna. This ensures the transmitter uses the proper antenna path and prevents transmit energy from feeding into the ADF system. The other options don’t perform this automatic routing: the Antenna switch module is a more general term and may not be the specific switching device in this system, the Direction finder motor handles rotating the ADF antenna rather than path switching, and the radio transceiver is the RF user of the link, not the switch that selects which antenna is active.

Switching the antenna path is done by a relay that changes connections when the radio is keyed. In this setup, the A-395 Relay Assembly sits in the antenna routing network and, when the radio is keyed for transmission, energizes its relays to connect the Comms antenna and disconnect the ADF antenna. This ensures the transmitter uses the proper antenna path and prevents transmit energy from feeding into the ADF system. The other options don’t perform this automatic routing: the Antenna switch module is a more general term and may not be the specific switching device in this system, the Direction finder motor handles rotating the ADF antenna rather than path switching, and the radio transceiver is the RF user of the link, not the switch that selects which antenna is active.