Which device is used to convert digital signals to analog signals for…
2026
Which device is used to convert digital signals to analog signals for communication over telephone lines?
Answer: B. Modem — ConceptCommunication channels may carry signals in analog or digital form. Interfacing equipment must translate data into a form the channel can carry and…
- A.
Router
- B.
Modem
- C.
Switch
- D.
Gateway
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Show answer & explanation
Correct answer: B
Concept
Communication channels may carry signals in analog or digital form. Interfacing equipment must translate data into a form the channel can carry and reverse that process at the receiving end.
Modulation places digital data on an analog carrier, while demodulation recovers digital data from the received analog carrier.
Application
The sending computer produces digital data.
For a traditional telephone line, a modem modulates that data onto an analog carrier for transmission.
At the receiving end, a modem demodulates the analog carrier to recover the digital data.
Contrast
A router selects paths and forwards packets between networks.
A switch forwards frames among devices within a local network.
A gateway connects unlike systems or protocols and can perform protocol translation.
Therefore, the required device is a modem.