"Frank Fox Box" LED Oscilloscope
An XY Oscilloscope that uses a matrix of 100 LED's to display the signal. The display is logarithmic, which gives it SPECIAL panning properties.
There is a quadraphonic/ surround version that uses four in rotation.
The advantage of logarithmic oscilloscope, over a linear one, is that it is also a level meter.
This provides a great deal more information (in linear, half the display is just 6db of information).
The unit has a signal clip light that comes on at digital full scale.
Whilst not suited to displaying wave forms, this unit is the best way to view the phase information in a stereo signal.
Unlike a conventional XY display, a mono signal does not change angle as it is panned from left to right. Instead the line goes along the bottom, and is then deflected straight up.
This is a property of logarithmic signals in a matrix. Nothing has been done to the signal.
Frank Fox first discovered it working as a mathematician. It wasn't until he talked to an audio engineer about it that he realised that it could be used as a metering system.
He also registered the patents for the prototype/ forerunner of the Rubiks cube.