How reliable is your microwave link?

We are often asked if our point-to-point microwave link is reliable. We are asked if rain or snow interfere with the signals. Our experience is that the link is extremely reliable (except when it gets hit with lightning). You can see a signal strength graph showing the measured signal strength for the link. A value of "2" is quite good, meaning that the link is operating at about 3M bps. The system has kept a value of "2" for many months now, even during heavy rains and heavy snowfall. Considering that the frame relay T1 line to our ISP operates no faster than 1.5M bits, this means that the microwave link is not the speed-limiting factor for our system.