Here is a schematic of the IDS setup.
The blue fiber-optic cable links the SSX gadget to the sensor. The blue box houses the mirrors, while the black protrusion holds the photo multiplier tube (PMT).
Here you can see the business end of the sensor with its top off. The PMT is in the smaller box at the end with all the wires coming out of it.
On the left is raw data from the PMT. Each line represents one cell of the PMT, and thus one frequency range. To the right is the processed speed data at t=58us converted in to a histogram.
Here is a series where the bidirectional flow is clearly visable.
