I just purchased the EMF-390 to have a low cost method of verifying if a wireless bridge antenna is receiving a signal and aiming a new antenna. I have not tried it yet but wondering if anyone else uses the device to try this.
Generally we are close enough to the antenna that we are connecting to so we can aim the antenna by sight. The bridge is in the 2.4ghz range but no SSID is assigned. It is just a signal. Once we aim it we are just assuming that it is able to talk. We can ask the networking group to go into the Cisco software and look at signal strength. But it is nice to have a small device that will tell us that a signal is present.