Ideal baud rate for 2km distance RF data transmission.

Hello!

I am using a MCU based on Atmega2650 using Serial1 to send data to TX RF transmitter. The frequency of the transmittion is 433Mhz and the distance is about 2Km.

My program sends data every 250ms.

To set the data rate I ask for you help. What would be the best rate for this distance? Should data rate decrease for higher distances?

Thanks.

Should data rate decrease for higher distances?

In general, with those radios, yes. However, I don't think you have a hope in hell of transmitting 2km using those cheap radios. A lot of people have trouble transmitting more than 2 meters with them.