The TX Gain Adjustment field in the gateway detail allows you to reduce the output gain of the gateway in the case when a high-gain antenna is mounted to the gateway. The TX Gain Adjustment should correspond to the gain that the antenna is adding.

The purpose of the adjustment is to be compliant with the radio regulations in your country. Our software by default instructs the gateway to send at the maximum allowed power in the specific band, so by mounting a high-gain antenna, you would be most likely violating the radio regulations.