Our owners were in the herring business years ago, and when the recording depth sounders came out they were amazing equipment. When passing over a herring bait ball the machine would go nuts and start darkening the thermal paper. The owners brother used to joke that the smell of the machine was as much an indicator as the paper graph of the fish below the boat. That was the smell of fish....
I have a few old electronics on the shelf above my desk as an indicator of just how far electronics have come, including a Furuni FE-450 recording sounder.
