The MF/HF transceiver fails to produce AF...

Question 1 / 27070Lxv7wrWShB1dOvmnhRS3

Question 1 of 27070Lxv7wrWShB1dOvmnhRS3

The MF/HF transceiver fails to produce AF output but the radio is powered on and "TX" is illuminated. What is the most likely cause?

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Question 1 of 27070

The MF/HF transceiver fails to produce AF output but the radio is powered on and "TX" is illuminated. What is the most likely cause?

🔍 Key Concepts

• MF/HF transmitter and receiver signal paths (difference between transmit (TX) and audio output (AF)) • Function of the Push-To-Talk (PTT) circuit in a microphone • What a failure in the AF (audio frequency) amplifier would do to sound in the speaker

💭 Think About

• If the TX light is on, what does that tell you about whether the radio thinks it is transmitting or receiving? • What happens to the audio path and the speaker when the PTT circuit is activated continuously (stuck in transmit)? • Which fault would most directly stop you from hearing received audio, while still letting the set power up and indicate TX?

✅ Before You Answer

• Confirm whether continuous transmit would mute or disable the receiver’s AF output to the speaker • Consider whether a shorted speaker would still allow any indication on the radio’s display and TX light • Think about whether a power supply crowbar would let the radio remain powered with TX illuminated

Question 1 of 27070

The MF/HF transceiver fails to produce AF output but the radio is powered on and "TX" is illuminated. What is the most likely cause?

The speaker is shorted out.

A shorted Push-To-Talk circuit in the microphone .

A "crowbar" circuit in the power supply has engaged.

The final stage of the AF amplifier circuit has failed.

Question 1 / 27070Lxv7wrWShB1dOvmnhRS3

Question 1 of 27070Lxv7wrWShB1dOvmnhRS3

The MF/HF transceiver fails to produce AF output but the radio is powered on and "TX" is illuminated. What is the most likely cause?

Back

Question 1 of 27070

The MF/HF transceiver fails to produce AF output but the radio is powered on and "TX" is illuminated. What is the most likely cause?