Which of the following connections is made between a computer and a transceiver to use computer software when operating digital modes?
The correct answer is C: Computer 'line in' to transceiver speaker connector. When connecting a computer to a transceiver for digital mode operation, the computer's 'line in' (audio input) connects to the transceiver's speaker connector (audio output). This allows the computer to receive and decode the audio signals from the transceiver.
The transceiver's speaker output contains the received audio signals that the computer needs to decode. By connecting the computer's line-in to the transceiver's speaker output, the computer can 'hear' what the radio is receiving and process it for digital mode decoding. This is one direction of the audio connection - you also need the reverse (computer audio out to transceiver mic in) for transmission.
Exam Tip
Computer receive audio = Line-in to speaker. Remember: To receive audio from the transceiver for digital decoding, connect the computer's 'line in' to the transceiver's speaker connector.
Memory Aid
"**C**omputer **R**eceive = **C**omputer **L**ine-**I**n **T**o **S**peaker (think 'CR = CLITS')"
Real-World Application
You're setting up FT8 operation. You connect your computer's line-in (microphone input) to your transceiver's speaker/headphone jack. When the transceiver receives a signal, the audio comes out the speaker jack and goes into your computer's line-in. Your FT8 software (WSJT-X) can then decode the received audio signals. This is the receive path of your digital mode interface.
FCC Part 97.3Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Computer line-out to transceiver PTT would control keying, not audio reception. PTT is for transmit control, not audio.
Option B: Incorrect. Computer line-in to transceiver PTT doesn't make sense - PTT is an output from the computer, not an input, and it's for control, not audio.
Option D: Incorrect. Computer line-out to transceiver speaker would send audio to the speaker, not receive audio from the transceiver for decoding.
题目解析
The correct answer is C: Computer 'line in' to transceiver speaker connector. When connecting a computer to a transceiver for digital mode operation, the computer's 'line in' (audio input) connects to the transceiver's speaker connector (audio output). This allows the computer to receive and decode the audio signals from the transceiver. The transceiver's speaker output contains the received audio signals that the computer needs to decode. By connecting the computer's line-in to the transceiver's speaker output, the computer can 'hear' what the radio is receiving and process it for digital mode decoding. This is one direction of the audio connection - you also need the reverse (computer audio out to transceiver mic in) for transmission.
考试技巧
Computer receive audio = Line-in to speaker. Remember: To receive audio from the transceiver for digital decoding, connect the computer's 'line in' to the transceiver's speaker connector.
记忆口诀
**C**omputer **R**eceive = **C**omputer **L**ine-**I**n **T**o **S**peaker (think 'CR = CLITS')
实际应用示例
You're setting up FT8 operation. You connect your computer's line-in (microphone input) to your transceiver's speaker/headphone jack. When the transceiver receives a signal, the audio comes out the speaker jack and goes into your computer's line-in. Your FT8 software (WSJT-X) can then decode the received audio signals. This is the receive path of your digital mode interface.
错误选项分析
Option A: Incorrect. Computer line-out to transceiver PTT would control keying, not audio reception. PTT is for transmit control, not audio. Option B: Incorrect. Computer line-in to transceiver PTT doesn't make sense - PTT is an output from the computer, not an input, and it's for control, not audio. Option D: Incorrect. Computer line-out to transceiver speaker would send audio to the speaker, not receive audio from the transceiver for decoding.
知识点
Computer-radio interface, Audio connection, Line in, Speaker connector
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.