*Question T4A07:
Which of the following connections is made between a computer and a transceiver to use computer software when operating digital modes?*  

*Correct Answer is  C: Computer “line in” to transceiver speaker connector*  

### AI Response: (may contain errors)  

To operate digital modes using computer software with a transceiver, the correct connection is:

**Correct Answer: Computer “line in” to transceiver speaker connector**

### Explanation of the Correct Answer:
- **Computer “line in” to transceiver speaker connector**: This connection allows the audio output from the transceiver (which is typically a modulated audio signal) to be fed into the computer's audio input. The computer can then process this audio signal for digital modes, such as PSK31 or FT8, allowing for decoding and transmission of digital signals.

### Why the Other Choices are Incorrect:
- **A: Computer “line out” to transceiver push-to-talk**: This connection does not transmit audio signals. The push-to-talk (PTT) line is used to control the transmitter, not to send audio. Therefore, this option does not facilitate digital mode operation.

- **B: Computer “line in” to transceiver push-to-talk**: Similar to option A, this connection does not transmit audio. The PTT line is for activating the transmitter, not for receiving audio signals from the computer.

- **D: Computer “line out” to transceiver speaker connector**: This connection would send audio from the computer to the transceiver's speaker output, which is not the correct direction for digital mode operation. The speaker output is meant for audio output, not for inputting audio signals into the computer.

### Summary:
- The correct connection is essential for enabling the computer to decode incoming digital signals and send outgoing digital signals through the transceiver.
- Always ensure that the audio paths are correctly set up to facilitate effective communication in digital modes.