Which element must be confirmed to resolve a radio that cannot transmit?

• A. The keying path and PTT are functioning
• B. The squelch is fully open
• C. The antenna is correctly matched to the RF channel
• D. The speaker is connected to the audio output

Answer: (A)

To transmit, the transmitter must be enabled by the keying path through the PTT. The PTT action provides the enable signal that starts the RF chain, so confirming that the keying path and PTT are functioning is what ensures the radio can actually produce RF onto the antenna. If this path is faulty, pressing PTT won’t engage the transmitter, and you’ll see no transmission regardless of other conditions.

Squelch, which controls receive ability, doesn’t affect transmission—opening or closing it won’t make the radio transmit. The antenna being matched to the RF channel is important for efficient power transfer and protecting the transmitter from reflections, but a problem there won’t usually stop the transmitter from being enabled; it would just reduce performance or risk damage if the match were severely off. The speaker connection affects audio output, not the act of turning on the transmitter.