9-4A2 C
 What fault may exist if a VHF radio receiver fails to produce audible output from the speaker and the squelch control has no effect?
A. A component in the RF amplifier stage has failed or the signal from a preceding stage is grounded. 
B. The Local Oscillator stage is no longer supplying a signal to the mixer stage at the correct frequency.
C. The AF amplifier may be defective or the transmitter Push-To-Talk circuit may be activated.
D. The mixer stage is no longer producing an output signal on the correct Intermediate Frequency (IF).
