i want to reduce the RX power

You can change the value of the TXPOWER register. This can be done in SmartRF Studio with the TX power pull down menu.

i want to reduce tx power all the time

can u tell me how to reduce using Samrt RF studio?

once plugged in my device in computer , i openned smart rf studio, and i reduced the tx power ,

and i unplugged it , again i plugged in but it shows previous default value

Hi

SmartRF Studio only controls the radio when it is connected to the PC. You have to reprogram the TXPOWER register in your own SW code to make it permanent.