[RC232] When I set the transmit power to the smallest value, is only the transmit power reduced or also the receive power?

The output power in TX is programmable, and will not influence on the receiver. The receiver will receive packets as long as the incoming signal is inside the dynamic range limited by the sensitivity limit (weak signal) and the saturation level (Strong signal).  You can use the RSSI to measure the signal strength of the received packet.

Last Update: August 8, 2017