9-18B5 C
Which of the following conditions could cause zero RF output in a MF/HF transmitter operating in the F1B FEC mode?
A. The connection of a transceiver is connected to a "Dummy Load" antenna.
B. The failure of the voice bandpass filter in the stage preceding the RF amplifier.
C. The activation of a "crowbar" circuit in the power supply to prevent an unregulated voltage increase.
D. The generation of a positive VCO feedback signal to a Phase Locked Loop circuit in the transmitter.
