How to know the signal levels of the links telemetry, RC and video?

I need to know the signal levels that telmetry, rc and video links had during the mission. Is there any way to know those values? or in the controller where I can observe these values ​​during the mission.

In case of not being able to collect these values, there is some way to know the loss rate that the links have had.

Maybe the logs give me that information??. If these is the case, somebody can tell me how to download logs.