What device is used to increase the measured loss in a circuit?

The device used to increase the measured loss in a circuit is a pad. A pad typically consists of resistors that introduce attenuation (loss) into a signal path deliberately. This is often necessary in communication systems to match signal levels, prevent distortion, or manage power levels effectively as signals pass through different components. By using a pad, engineers can adjust the signal strength to maintain optimal performance and avoid issues such as overloading or interference in network devices.

In contrast, an amplifier is designed to increase the signal strength, which does not align with the requirement of creating an increased loss. A router primarily directs data packets between networks and does not serve the function of modifying signal loss. A switch connects multiple devices within the same network but also does not alter the loss characteristics of the circuit. Therefore, the pad is specifically utilized for adjusting loss levels, making it the correct choice.