Back in the last century I was climbing mountains looking for airplane crash sites (I still do this). My father and I were out 4 wheeling and camping on a trip where I decided to climb yet another mountain while he stayed down in the valley fishing.

Using FRS radios we coordinated my flashing him with a USN glass jet seat pack survival signal mirror from the mountain.

By radio he could tell me if I was on target and then I could concentrate on that area so he could video the effect.

It's really quite awesome!

Here it is posted to my YouTube channel-

BNCAntenna's YouTube channel