What component of a RADAR receiver is represented by block 47?

The RF Attenuator is a crucial component in a RADAR receiver that functions to reduce the strength of the incoming RF signal before it is processed further. This is important because strong signals can cause saturation in the subsequent stages of the receiver, leading to distortion or failure to detect weaker signals.

In RADAR systems, the RF Attenuator helps to manage the dynamic range of the receiver, allowing it to handle a wide variety of incoming signal strengths without degrading performance. By controlling the gain of the signal, it ensures that the receiver operates effectively across different operational scenarios, maintaining an optimal level of sensitivity.

While the ATR box deals with automatic temperature regulation and the TR box pertains to the transmission-reception function, and the Crystal Detector is responsible for demodulation, neither of those components serves the specific purpose of attenuating the RF signal as the RF Attenuator does. Thus, the representation of a RADAR receiver's component as the RF Attenuator is appropriate due to its specific role in managing signal strength within the receiver's signal chain.